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| kramdra |
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kramdra
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tahrey
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 Posted: 14:15 - 09 Oct 2012  Post subject: |
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| kramdra wrote: | why would you want to?
125's sound like they are abo.... (etc) |
Did you actually read any of what I put about a/ what I actually had in mind and b/ why? Or did you just feel the need to go off on an anti-small-capacity rant?
1/ A minor bump in power (as in, 20%, which is a hell of an improvement when you've got shit-all and end up with the throttle wedged fully open more often than is comfortable) would be quite nice for the riding I do on it, but I don't need masses of thrust and I don't want to harm the economy or longevity too much. It's still going to be a mainly urban commuting and utility machine, just with slightly improved short-haul intercity ability.
2/ Keeping it in the lower tax and insurance bands is also a thumbs-up. It would however, technically speaking, be legally qualified to tow a trailer and have a sidecar fitted, which amuses me even if I would probably never actually do it.
3/ The relevant bit of the engine in question is now surplus to requirements, and is going to be removed ANYWAY... then either worked on in order to repair it, or just scrapped. Basically the difference in procedure would amount to a) putting a different crankpin back in place of the OEM one (which would have been removed and refitted anyhow) - or modifying it? b) shortening or replacing the conrod. (and maybe c: rejet the carb and open up the breathing a bit). Should the work turn out possible, affordable, and ultimately successful, I could then switch the bottom end back on to the top in place of the imperfect-but-good-enough ersatz one I've now acquired.
I'm not pulling the bike to bits JUST to do this. It's already being worked on for other reasons.
4/ it would actually lead to less hammering of the thing on full throttle and to lower rpms whilst cruising so it would sound LESS like it's going to explode.
Jeez.
The main question is over whether there's enough leeway to get away with it - ie is the barrel/crankcase mouth wide enough, is there enough clearance in the case (sump) itself, and would the piston skirt still clear the deck/flywheel - and just how much it would cost to either get hold of the relevant parts or have the work done to modify the existing ones (...it's certainly not something I can do myself, as simple as it is in concept).
Last edited by tahrey on 14:36 - 09 Oct 2012; edited 1 time in total |
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tahrey
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| Posted: 14:40 - 09 Oct 2012 Post subject: |
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Another one not reading.
I passed my tests a full frigging year ago.
If I hadn't, I wouldn't be considering upping it to ~150cc.
And I wouldn't be doing it either if anyone sold bikes in this country that actually fit my everyday requirements. What do we have... somewhat underpowered 125s... a tiny handful of 250s, of which maybe one or two models are actually economic rather than baby racers (and whose used prices end up inflated as a result)... and that's about it. Mayyybe a couple of 185-200cc enduros too.
Like I've put elsewhere, it's like having a choice of 400 or 1000cc cars whilst learning (with the occasional rare 750 or 800), but then post-test cars almost all start at 2000, and most are 3 litre or larger. Never mind that a 1200 would be the best fit for punting around the city and occasionally taking a sub-hour toodle along the motorway at roughly 70mph. I don't often go on pleasure rides, I haven't the time or the fuel money for it, or any local crowd to join the pack of.
It probably won't happen anyway, as there are far too many barriers. But I think it would be interesting to have a go, if it should actually turn out in any way viable.
It's -not- supposed to be an expensive mod. The largest part of it is something I was already being recommended to try to fix my existing big end bearing issue. If it turns out to be costly (more so than part-exing for a bigger bike then paying the extra fuel, servicing and insurance costs would be, anyway), then I won't bother.
What do we have to do for people to pay attention in this world eh?  
Though if you can recommend me a bike I can buy fully formed, in the UK, without spending a metric fuckton of money on purchase, servicing or insurance, that'll provide 15+ horse and nudge 100mpg, then I'm all ears. |
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| Kickstart |
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Kickstart
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| Posted: 23:48 - 09 Oct 2012 Post subject: |
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Hi
I would doubt a bored out CG would get anywhere near 15hp (that is a bigger increase than the change in capacity, and without a load of head word and suitable carb you would struggle to get that much), and suspect it wouldn't do 100mpg afterwards either.
The older CG125s were most certainly pushrod engines. They were developed as a cheaper to make and tougher bike compared to the OHC cam Honda singles already in production in the early 1970s (which had a bit of a habit of seizing the cam into the head when people ignored the oil changes). Possible some of the recent ones are using the OHC engine though.
With the basic CG engine you are pretty limited. With the cheap cam setup there is little useful you can do with the cam timing.
All the best
Keith
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| Teflon-Mike |
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Teflon-Mike
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| Posted: 03:07 - 10 Oct 2012 Post subject: |
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| kramdra wrote: | dont agree if for no other reson, its the shortest post Ive seen you type, so it must be wrong :p
willing to bet most thirty five year olds will have lost half of their ponies
but out of interest, has it been done before? that is, disabling cylinders to meet CC requirements? |
The CB125 uses the little benley bottom end; its actually quite a hardy wee beastie, provided they get regular oil changes. They do loose power from cam-chain slack retarding the cam-timing though, and yeah, that and ring bore can make big difference, but dont take much to pep them back up, rebore, and a retime.
Disabling cylinders? Yup. The wall-of-death riders often use 1930's Indian Scouts, with the front piston & con-rod removed to run as a single as a 'single'...
Remember suggestion being made repeatedly in the early 125 Learner-Law years when old 250's were ten a penny and people almost couldn't give them away, to remove a piston & rod to make them 125's.... dont think any-one ever managed to make it work, or convince the authorities it was then learner-legal!
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tahrey
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Posted: 14:09 - 10 Oct 2012  Post subject: |
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| Kickstart wrote: | I would doubt a bored out CG |
I'm talking about stroking it though.
| Quote: | would get anywhere near 15hp (that is a bigger increase than the change in capacity, and without a load of head word and suitable carb you would struggle to get that much), and suspect it wouldn't do 100mpg afterwards either. |
I think you might be conflating the two different things I was mulling over.
1/ A "simple" stroke job on the crank and conrod, with any necessary airway and carb improvements to come later. This would increase the capacity to maybe as much as 148cc from 124cc, depending on how far it could actually be taken - there already doesn't seem to be a huge amount of clearance between where the piston skirt would go and the outer radius of the inner flywheels.
148 / 124 = approx 1.2x, or +20%. It starts with about 10.8hp (8.1kW)... let's say 11 so I don't have to break the calculator out. 11 x 1.2 = 13.2hp. I actually estimated 12.8 IIRC. Which is still +2hp, which means flat out around 65mph I suddenly have an extra 2 horsepower accelerating me to higher speeds, rather than being in thrust/drag equilibrium.
And even if it hasn't got the airflow or fuel supply capacity to satisfy that meagre improvement, then it sure will help the upper-midrange torque. 10.8 DIVIDED by 1.2 = 9.0... so potentially the power band is extended down the rev range to the point where it was previously only making 9hp. So going uphill at speed in 5th is suddenly slightly quicker (as there's that extra couple hundred watts - or the entire power output of an electric bicycle - giving it a boost and maintaining speed at sub-peak-power rpm, where it would otherwise be slowly losing pace), as well as more easygoing because I don't have to change down as soon.
All the carburettor, intake, valves and exhaust care about is the amount of air going through per unit time (OK that's an oversimplification, and we're ignoring the effects of ignition advance, flamefront speed in the cylinder etc, but roll with it for now). If it's able to flow enough air, and fuel, to make 10.8hp at ~8750rpm with 124cc's, then why not almost as much power at 7250rpm with 148cc? By which speed I'd have already shifted down to 4th on the 124?
Like a poorly tuned 1200cc car vs a 1000cc in good condition, sort of.
The mod would also turn the engine from oversquare to very slightly undersquare, which may hamper the rev-ability somewhat - not that I generally take it anywhere near the redline anyway, except in 5th, because there's no benefit to it in the lower gears - but be even better for torque.
| Quote: | The older CG125s were most certainly pushrod engines. |
My 2006-vintage, very nearly end of line CG125 is quite definitely a pushrod engine. With a single lobe cam.
| Quote: | With the basic CG engine you are pretty limited. With the cheap cam setup there is little useful you can do with the cam timing. |
I'm just after a rough and ready capacity increase. They already made 150cc versions of this bike elsewhere, as well as 100s, and as far as I can tell that was through changing the stroke. If they bothered changing anything else at the same time other than the carb jetting I'd be quite surprised. Like you say: cheap and simple bikes.
The "15hp" version would presumably be the ~175cc achieved by first stroking it to 148cc, then applying a different potential mod (using barrel liner and piston from a bigger bike) to effectively bore it out. Said mod alone would have achieved 146cc, and an even-more-oversquare engine more happy revving for its power rather than mostly offering improved torque slog.
175 divided by 125 is 1.4, or +40%. 11 x 1.4 = 15.4hp. QED.
Not that I was ever offering my figures as absolute set-in-stone infalliable predictions. But these kind of improvements are common first steps on the road to gross power output improvement, before you get into all the finessing of ports etc... and would be plenty enough for me. To see the actual results, and get the most out of it, would then require a dyno run, probably repeated runs with someone adjusting the carburettor each time until it gave the best possible power.
The economy thing, I already ran through, but it's the part that's most up in the air out of everything. It's just too complex an issue to judge without actual on-road testing, before (which, really, I've already done) and after the mod. There's half a chance it could actually improve. Or it might degrade so much that it's just not worth running the bike with the mod in place. Who knows. My best estimate is that it might lose 10 or even 15% in town when riding very lightly (so falling to 100mpg from the 115 I've seen when actually riding that way...), but probably no more than 5% when on fast cruises that take advantage of the increased torque but not the power (eg ~90 down to ~86mpg). |
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honda cg 1992
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kramdra
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Teflon-Mike
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| Posted: 03:30 - 12 Oct 2012 Post subject: Re: i want to change my engine in my cg |
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| honda cg 1992 wrote: | i want to change the engine in my cg to a honda cb250 twin engine but dont know if it will fit in the frame and if the engine mounts are the same can enyone help me ? |
CB250 Twin, covers CB250T, CB250N & CB Two-Fifty, covering, about 30 years of production, three very different families of engine, and numerouse differences between model years and variants.
Doesn't really give us much to work with.
What I can tell you is that none of them will bolt directly into the CG frame without modification around the mounts at the very least.
I can also tell you that if you have the daft idea of leaving the 125 panels on the side and riding the drum braked desaster in waiting on L-Plates, NO-ONE will be kidded into believing its still a 'learner-legal'
Meanwhile the 250 twin motors are, for the most part not actually that powerful. Early ones particylarly, actually make less power than a similar age CB125 twin, but even THE most powerful of the bunch, if not suppering severe cam-chain maledies, wont actually out-pace a decent de-restricted two-stroke 125.
It is, in short a rather pointless and fultile endevour that is no small engineeering challenge, to create a mongrel vehicle that is likely to be illegal, obviousely illegal, potentially lethal, and more effort and expense than simply buying a bike that's built to do what you want, and either riding THAT without a licence, and breaking fewer laws doing so, or getting the licence to ride it legally.
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| unitynotsocri... |
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unitynotsocri...
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Posted: 10:58 - 12 Oct 2012  Post subject: |
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i wonderd if BCF should have a seperate ' i'm a looney with a cg' section.thanks to massive chinese production 'cg' heads are likely to become a big weird subgroup,like strokers.......as in ....slightly unhinged.
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Kickstart
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| Posted: 19:15 - 12 Oct 2012 Post subject: |
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| tahrey wrote: | All the carburettor, intake, valves and exhaust care about is the amount of air going through per unit time (OK that's an oversimplification, and we're ignoring the effects of ignition advance, flamefront speed in the cylinder etc, but roll with it for now). If it's able to flow enough air, and fuel, to make 10.8hp at ~8750rpm with 124cc's, then why not almost as much power at 7250rpm with 148cc? By which speed I'd have already shifted down to 4th on the 124? |
Carbs and exhausts on anything with a vague state of tune are set up to work over rev ranges. However the CG might well be too basic for that. However you are also limited on valves, etc.
As to to revs, etc. You would need to work out the torque and the gearing. Torque x gearing gives you rear wheel thrust.
Honda claim over 14hp for the CG150 in Brazil, although that is the now OHC engine (which does away with a lot of the limits on the CG design). The older CG150 appears to be a CG125 with a larger bore but the same stroke (and about 13hp). Not sure the larger piston / bore will fit into the CG125 crankcases without changes. Stroking the engine without a suitable crank from another bike would be far from simple.
All the best
Keith
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tahrey
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| Posted: 17:20 - 15 Oct 2012 Post subject: |
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| Kickstart wrote: |
Carbs and exhausts on anything with a vague state of tune are set up to work over rev ranges. However the CG might well be too basic for that. However you are also limited on valves, etc. |
Uh-huh, but, as I said, do said parts give a crap about the size and frequency of individual air pulses - at least, on a 4-stroke where AFAIK very little of a crap is given about tuning for backpressure waves etc - or are they simpler beasts that care only for how much air is rushing past on average per unit time?
Because, sure, I'd be a bit put out to find that the power output is actually limited by the intake/exhaust system restrictions and the valve diameter/opening, but it'd still be nice to have a similar wedge of power and improved torque further down the rev range. Especially as, presuming the altered parts didn't end up failing prematurely anyway, this would help future engine longevity and possibly even fuel consumption.
I expect that even if those bits are restrictive there should be a -slight- power increase, as the greater cylinder volume would be able to both suck and blow with 20% greater force, creating harder intake vacuum / exhaust pressure and therefore higher air velocity (and, yes, i know, greater turbulence and drag...) through those fixed size apertures.
| Quote: | As to to revs, etc. You would need to work out the torque and the gearing. Torque x gearing gives you rear wheel thrust. |
Que?
Revs in relation to what?
I've already put the calculator hours in to figure out (and order) what sprockets I'll immediately need to compensate for the XR block gearing, and what both the stock engine and a stroked one (assuming an idealised output boost) should be capable of maintaining top whack with... did some of it ages ago, now. The end result in fact on 15/44 (on order...) will give a slightly longer 5th than the stock CG (might mean 1st is a touch long, but it was the closest usable one to stock which meant I can keep the same chain length and switch over to 15/45, 14/45 or 14/44 if I like), so providing I don't loose power for some reason as a result of this work I can see if the needle still sits at the same place or higher/lower when I open the taps. Though far more briefly than I did before. I don't fancy going for the sound barrier again unless/until I've got longer gearing on.
If it's in relation to something else I'm afraid you've lost me.
| Quote: | The older CG150 appears to be a CG125 with a larger bore but the same stroke (and about 13hp). |
Potayto potahto. 12.8 == 13.0, right? 
Presumably the more oversquare design (ie able to rev that bit harder) and their ability to more precisely engineer it for 149.1cc by design instead of 147.9 by happy accident means an extra 0.2hp was found from somewhere. Or it's just rounding error.
| Quote: | Not sure the larger piston / bore will fit into the CG125 crankcases without changes. |
If there's any way of actually getting hold of an official top end without ludicrous expense then I'd certainly give it a test fitting... Unfortuately 99.999% of the CG150 kits and parts out there appear to be chinky copy BS, and will only mate up to knockoff engines which are subtly different from the japanese / turkish / brazilian ones. And have the net effect of dragging the disappointing 125cc output up to about the same level as the original engine.
Apparently boring out the standard one far enough to accept a suitably large piston will almost certainly break into an oilway, so I presume any official higher-capacity one either has a redesigned barrel, or does away with the liner somehow (as the general idea appears to be "remove liner, bore out barrel, fit oversized replacement liner"... the alternative of boring the liner itself apparently just leads to breakage). This might well mean it won't fit with the 125cc casing any more.
| Quote: | Stroking the engine without a suitable crank from another bike would be far from simple. |
Hmph. The site I was reading the idea from suggested it was possible to modify the stock 125cc one; displace the crankpin 4.75mm further out, and shorten the conrod itself by 9.5mm (presumably by cutting a bit out and welding it back together). Is there no possibility of that? Or would it lead to swift and hilarious failure for some reason?
OTOH what's the likelihood that there might be another bike out there with a suitable-length conrod (even if it means packing a gasket here or there and altering the valve clearances quite drastically) and/or crank?
EDIT: Actually IIRC the manual welding etc was an alternative to hunting out a particular crankset from a different bike ... I forget which by this point. Though that then of course assumes it's going to mate up nicely with the primary reduction and cam gears...
There seems to be more than enough side-to-side clearance to allow the conrod to move further to the side, but I still dunno about whether it would have clearance vs the "sump", front bulkhead, gearset, or piston skirt. I'm a fair way from being in a position to pull my old, knackered bottom end apart and see what's what. It's almost certainly going to be a 2013 thing if it happens at all. Heck, I think I'm probably going to return the tools I bought for alternator rotor pulling, for the time being, as I've found I misidentified what the rotor actually was and the new block DOES have one on it after all... which means the block ain't gonna get split any time soon.
One thing at a time - get bike running. Sort gears/chain. Fix car. Fix less pressing bike issues (headrace / rear wheel bearings being old but not yet decrepit, front tyre, side stand...). THEN bugger about with this. |
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Teflon-Mike
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| Posted: 18:37 - 15 Oct 2012 Post subject: |
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| tahrey wrote: | | Quote: | Stroking the engine without a suitable crank from another bike would be far from simple. |
Hmph. The site I was reading the idea from suggested it was possible to modify the stock 125cc one; displace the crankpin 4.75mm further out, and shorten the conrod itself by 9.5mm (presumably by cutting a bit out and welding it back together). Is there no possibility of that? Or would it lead to swift and hilarious failure for some reason? |
ever seen a con-rod 'let go' 
These things are forged, tempered and peened for a reason, they are probably THE most heavily loaded component in the entire engine, and you have the notion to do a cheap cut & shut job on one!?!?!
As Keith says, its doable, and the blurb in your article isn't utterly beyond credance.
Modern 4-stroke as we know it is based on the De-Dion/Minerva motor of the turn of the 1900's.
De-dion basically value engineered the best of the best of teh pioneering era, and distilled it down to a light, fairly simple, compact and powerful little motor, and demand outstripped his small manufacturing capability enormousely, hence seriel manufacture was licenced to Belgian Minerva.... people like Triumph started making motorbikes using proprietyr Minerva engines, but demand soon outstripped even thier manufacturing capability & the licences were franchised.
Harley & Davidson's first motorbike was actually based on American Re-Prints of 'one engine' blue-print licences sold in Europe, that were widely copied and published in magazines in features like "How to build your own De-Dion Engine" or "Improvements for the more demanding gentlemen making thier own Auto-Cycle motor"
Longevity of the pressed up crankshaft is legacy of this pioneering era and the popularity of the 'blue-print-licence' De-Dion engine, that could be built pretty much from scratch, but by the 1920's local foundries & blacksmiths often had paterns for the commonly asked for components and engineering workshops were knocking out 'off teh shelf' cranks and stuff... my Grandad used to recount tales of being sent to ball-brothers to fetch a new De-Dion 'Biscuit-Tin' crank-case after school, and helping his Dad built up an engine to power a generator for a farm or country house he was 'electrifying' (Old boy was a pioneer electrician!)
Pressed up crank-shaft is pretty low tech, and with a lathe and know how to taper turn, maybe drill & peg, possible to knock up a pressed up crank in maybe a day, and running on caged bearings it need not be tempered or case hardened even..... though if you want it to run at high rpm and survice higher powers you'd be advised to, then critically balence it.
But its precision machining, at the next level beyond average DIY bodger.
Con-Rods? Yup them's the tricky bits. The old De-Dion Biscuit-tin engines, you could get away with something a bit brick-shit-house, and a thick enough bit of steel plate, with a little ductility could actually be a bit helpful, bending rather then breaking if over-reved or run too long at load.... but, talking engines that generally ran at pretty low rpm, as in hundreds not thousands, under comparitively low load, 1bhp per cubic inch or less, with little variation in engine speed.
Scratch building you would normally start with stock rods and work from there.
Longer the rods are by the way, the smaller angle they have to travel between 90 before and after TDC.
Accelerated less by smaller displacement in same time for a given rpm, they are often subjected to a lower loading despite the extra mass and leverage of being physically bigger.
Going to a longer stroke; increases the displacement a conrod has to deflect to start with, so going longer stroke and shorter rod, is NOT great for con-rod stress, BEFORE you try cutting the ruddy thing in half and welding the forged, tempered and case hardened metal back together......
Also on the notion of gaining displacement from increasing stroke:
Power = Cylinder Pressure x Engine rpm x Cylinder Dispalcement (give or take a couple of constants of proportionality)
Makes no odds to power whether you get it from square bore & stroke, undersquare 'thumper' or over square screamer, for the most part, just how big the put is.
Capacity = Pi Bore squared, over four, times stroke.... (if my o-level maths is recalled correctly!)
So doubling the bore gives 4x the capacity where doubling stroke just doubles capacity... ie you get much more capacity from boring, which is easier, than you do from stroking which is harder.
I would be looking at ways to overcome the topographical dificulties of boring out fixed bits, rather than looking at trying to scratch build completely new whirly ones.....
Crank-Case aperture could be opened up with a hand file to take a bigger cylinder, push-rod galeries and oil ways drilled to suit in re-linered barel, which could even be lined up slightly off centre on the cases if needs be, all by changing shape of 'fixed' and reletively unloaded components!
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My Webby'Tef's-tQ, loads of stuff about my bikes, my Land-Rovers, and the stuff I do with them!
Current Bikes:'Honda VF1000F' ;'CB750F2N' ;'CB125TD ( 6 3 of em!)'; 'Montesa Cota 248'. Learner FAQ's:= 'U want to Ride a Motorbike! Where Do U start?' |
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| N cee thirty |
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Kickstart
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| Posted: 19:05 - 15 Oct 2012 Post subject: |
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| tahrey wrote: |
Uh-huh, but, as I said, do said parts give a crap about the size and frequency of individual air pulses - at least, on a 4-stroke where AFAIK very little of a crap is given about tuning for backpressure waves etc |
They are VERY important on any performance 4 stroke. Not so much restrictive more the design of exhausts / intakes give you extra power. Valve timing helps greatly but you are very limited on a CG.
| tahrey wrote: | Que?
Revs in relation to what?
I've already put the calculator hours in to figure out (and order) what sprockets I'll immediately need to compensate for the XR block gearing, and what both the stock engine and a stroked one (assuming an idealised output boost) |
Unless you know the torque curve then it is just a guess. How much umph you have is down to torque * gearing, and whether that thrust overcomes drag at that speed. From power and revs you can work out torque.
| tahrey wrote: | Apparently boring out the standard one far enough to accept a suitably large piston will almost certainly break into an oilway, so I presume any official higher-capacity one either has a redesigned barrel, or does away with the liner somehow (as the general idea appears to be "remove liner, bore out barrel, fit oversized replacement liner"... the alternative of boring the liner itself apparently just leads to breakage). This might well mean it won't fit with the 125cc casing any more. |
Doubt they bothered to move an oilway (possible though), as that would mean moving the feed from it from the crankcases / to the head (would seem pretty pointless to have extra basic parts to make). I thought the problem was the crankcase opening needed modifying.
| tahrey wrote: | Hmph. The site I was reading the idea from suggested it was possible to modify the stock 125cc one; displace the crankpin 4.75mm further out, and shorten the conrod itself by 9.5mm (presumably by cutting a bit out and welding it back together). Is there no possibility of that? Or would it lead to swift and hilarious failure for some reason? |
It is WAY more complicated that that.
You might be able to move the crankpin out a bit, if it is a pressed together crank. Easiest way would be to find a rod with a larger big end bearing and offset bore the crank webs out (VERY accurately) to take it. Depends how much meat there is on the crank webs as to whether you could get away with this.
Welding a rod together might survive long enough to set the idle speed if you were lucky! Put a spacer under the barrel and use the original rod.
| tahrey wrote: | OTOH what's the likelihood that there might be another bike out there with a suitable-length conrod (even if it means packing a gasket here or there and altering the valve clearances quite drastically) and/or crank? |
Quite likely. Rod length is important and will affect engine characteristics. However if you do get one to fit the crank and which is roughly the right length then it would be far easier to machine up a spacer to raise the barrel / machine off the bottom of the barrel to lower the barrel and keep compression about the right.
Finding a suitable crank that could be modified to fit won't be easy. Unless you could salvage the crank webs and rod from something like an XL185 and press those onto CG crank end outers.
All the best
Keith
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| Posted: 13:02 - 16 Oct 2012 Post subject: |
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| Kickstart wrote: |
((air pulses))
They are VERY important on any performance 4 stroke.
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OK? How so? (serious question)
Seeing as I've never really seen such things discussed before in this field. The first stage mods in terms of airways appear to be opening up the intake and exhaust systems to allow higher flow, but there's no discussion of actual "tuning" (like you would a musical instrument).
| Quote: | Not so much restrictive more the design of exhausts / intakes give you extra power. Valve timing helps greatly but you are very limited on a CG. |
This is part of why I'm wondering if there would be any benefit in changing parts other than increasing the displacement. It's already so low-tuned compared to pretty much anything except an Innova or other low-end scooters (which are rev limited) that I'm not sure whether it would have much knock-on effects elsewhere. Sort of like, harking back to the old cars again, my being encouraged to "just drop a 1.3 in" to my old Polo; all they meant with that was the block, ECU and probably the head if it came with. Everything else could be kept original. Again, pretty low tune engines (45 and 55hp from 1050 and 1275cc) and superficially very similar, just one was about 20-25% higher displacement than the other.
(And while we're at it, having done the maths on power, gearing, etc, I bolted a 1.3L 5-speed gearbox to said (4sp) 1.0L, and it worked just peachy. 5th was maybe 1 or 2mph short of 4th when going for broke, but otherwise it was just a much nicer cruiser from 30 up to 80ish mph, with an occasional need, on steeper hills, to drop back into the gear it already would have been in anyway)
| Quote: |
((revs, torque))
Unless you know the torque curve then it is just a guess. How much umph you have is down to torque * gearing, and whether that thrust overcomes drag at that speed. From power and revs you can work out torque. |
Yeah-huh, I know all that 
Let me open up my head and expose the workings of the maths done so far.
And I haven't got anything but the most basic idea of the actual torque curve given that no-one ever bothers to dyno these things, much less put the results online, but we do at least have a couple of manufacturer-provided data points, and other ones around them can be determined to a certain level of bodgeworthy "accuracy" empirically and using some reasonably proven assumptions for low-tune, torque focussed 4t engines (worked for the Polo, has a good chance of working here; if it doesn't, it'll only affect me). Plus the gear development is both known, and is anyway pretty simple to work out with the bike on its centre stand, left hand cover taken off and spark plug taken out but chain and sprockets hooked up - a position it will be in partway through the rebuild.
Said "hard" data points (which mine seems to slightly exceed?) being the peak torque and peak power, which both allow you to work out the other figure. 7000rpm nets you 9.8Nm, or approx 9.5hp; 8500~9000 (depending who you believe) gets you about 10.5 to 11.0hp... most commonly stated is 10.8hp, giving approx 8.6 to 9.1Nm at those rpms. So the torque is pretty flat and has only fallen off a little by the time power peaks, but we can assume it's falling pretty hard by the upper end of that vague rev band, and so peak power won't be maintained very far beyond 9k; it should be assumed as the maximum engine speed we tune our gearing to give max speed at.
Other points include the rev limiter (10500 or 11000 "depending", presumably set to give 2000rpm headroom above peak power), by which point on this bike the power has dropped a fair bit. 65mph on the clock in 5th isn't too hard, and 70 can be had fairly often. But 56 in 3rd is a struggle, and 68 in 4th (the respective limiter cut-in points) can only be had down a decent hill - it's much more productive to shift up around 45/55, and no later than 50/60.
Using some very basic assumptions about drag vs power (precise enough for our needs), that gives us maybe 8hp just before the limiter cuts in, or 5.5Nm. Which isn't so much of a useful thing to know in itself, but does give us the ability to build an idealised guesstimate curve between the "known" peak power and the limiter. 4th and 5th are close enough that the potential speed in this zone, rev drops etc could help decide between different sprocket sets or even cogs to swap on the gearbox shafts (if THAT's doable).
In the other direction, another bit of fudging assumes that the torque "dome" is relatively symmetrical, so we may have 9.1Nm at (7000-1500=) 5500 = 7.0hp, 8.6Nm at 5000 = 6.0hp, and 5.5Nm at 3500 = 2.7hp (the latter being enough for roughly 30ish mph flat out, and it will accelerate - slowly - from 25 at those actual revs even up a slight hill...). As I've found the full-throttle power output basically collapses below that rough rpm, and builds only fairly gradually towards the midrange, I'm happy to go with that just for the purposes of guiding initial decisions.
I mean, it's not like I can't then change the sprockets and chain in response to observed characteristics once the thing's built. It's a lot easier a job than replacing the engine, which I'm halfway through, stalled only by Honda's Brazilian factory-spec impact wrenches being far more resilient than my shitty Halfords socket adaptors. In fact it's the planned "second stage", as the initial build will be with XR internal gears but CG sprockets... I expect it'll run out of puff noticeably earlier than the bike did last time it was running properly, and comfortable cruising won't really be possible above 60mph. It already tended to rev beyond the apparent peak power point in 5th anyway.
Not having a tacho (or a home dyno) does make things a bit more guessworky, as I have to try and figure existing specs from the speedo, calibrating it vs GPS; as does the vagueness of the peak power and rev limiter figures even from Honda themselves.
All the same, the near flat torque band in that 1500~2000rpm-wide torque-to-power zone, which just rises slightly as rpm falls, at least makes me confident that it would be pretty difficult to properly cock up the gearing. It would basically take putting a relatively extreme sprocket kit on from completely the wrong year of bike.
Using the aforementioned basic power-vs-drag / top speed algorithm (haha... that's making it a bit grand... it's basically taking the square root of the difference between developed power and using it as a multiplier for the current top speed), it should be possible to maintain a good 61mph at 7000rpm, and even about 50mph at 5250rpm - below which it might become hard to keep the bike moving at all in still air; which means top gears of 8.7 and 9.5mph per 1000rpm, versus the current estimate of "about 7.4mph/1000" (80mph / 10750rpm).
So in order to lose 4mph off the official top speed, at quite relaxed rpm, would need something like 15/41 sprockets on a CG box (or 14/35 with the XR), way beyond what I have planned. Turning 5th into an unusable super-overdrive would require that same 14/35 on the original box or 16/37 with the XR.
That plus it revving out rather happily on the stock gearing makes me figure that said gearing can be lengthened at least a bit without affecting top speed one iota, or maybe even improving it. The old plan was for 14/43 or so (mayyyybe 14/42 or 15/45) - which now would need to be around 15/42 or 43 with the XR box - which would move 65 down from a conceptual 8800rpm or so to 8200~8400 (or 8300~8500 now).
Best case scenario would therefore place the official top speed just below or bang on max power instead of some way beyond it, and grant a slight power boost in the mid 60s up to 70mph range. Could give a 0.3hp boost at 65 in the best case, and as much as 0.8hp at 70 itself.
Small cheese in a world of 100hp+ superbikes and all that, but for changes that can be made at very nearly no effective cost, as part of an existing repair procedure, in order to give a better everyday ability to stay with traffic and not knacker the machine in the process, it could be very vital. That best-case 0.8hp is an almost 9% improvement on what the engine is theoretically already producing, and it comes with a more than 600rpm reduction in speed rather than an increase. It also still represents a good 500rpm reduction even at a more sensible high-50s cruising speed (or, 60 on the clock) without hampering much of the ability to maintain said speed, as we're still somewhat above peak torque and so in the main everyday high-power rpm zone.
Worst case for the same tweak, operating within the variability of known figures and using the fudged curves, would put 65mph at a point where the engine's only shoving out 10.3 instead of 10.8hp (assuming a flat line on the power chart from torque to power instead of a parabola that's a function of parabolically falling torque). It doesn't often feel like it's got less than 0.5hp to spare when pushing through 65 on the clock, but that slight shortfall in nonoptimal conditions (if it was in a state where 65 was absolute Vmax before, then it'd now only manage 63-64...) may be worth it for an ultimately higher top end and less wear on the reciprocating bits. As 4th is also raised at the same time as 5th, it should be possible to drop into it around or just above 60 instead of in the mid 50s in order to maintain good hill climbing or into-headwind speed, well before being down on the ("max 61") torque slog zone.
In either case, 1st is going to be lengthened a bit (especially given the overall tighter XR gearing), so ultimate off-the-line launch force might be a bit reduced, along with the first second or two's acceleration, but after that it's fairly moot up into the 60s. The same average amount of power is developed, you just shift gear at a different point. Simulations using other people's software show that ultimate quarter mile performance may suffer by a small fraction of a second - or in other words I might lag by a couple metres behind a ghost rider on the original bike. As I often don't launch absolutely as hard as possible and then short shift anyway, I'm not that bothered. The one thing I will have to look for is the raised minimum comfortable 4th-5th shift, which might now be almost as much as 30mph... 
After all that, I might then try fitting a screen and see if it helps with the aero. Faster -and- more economical if so, can't complain.
 How's that for you?
For the 148cc re-stroke, take all given power/torque figures and multiply by 1.19, and all maximum speeds at particular rpms by 1.09, then consider those as the "best case", and adjust gearing to suit.
IE 65 top speed increases to 70, maybe 71. Lengthen that to 72~73 if we assume the regearing itself gives the bike a new top speed in the 66~68mph range.
61 max at peak torque increases to 66~67 itself.
And you'd even see nearly 55mph at 5250rpm, if you went crazy with the gears.
More realistically, that means there'd be plenty in reserve at, say, 57 and 43 with those rpms when re-gearing for 69 @ 8500 / 71 @ 8750 / 73 @ 9000 and an assumed typical Vmax of 70.0 with the engine favouring slightly lower rpms after the change)
| Quote: |
((reboring issues, risk of breaking oil system or fouling on mouth))
Doubt they bothered to move an oilway (possible though), as that would mean moving the feed from it from the crankcases / to the head (would seem pretty pointless to have extra basic parts to make). I thought the problem was the crankcase opening needed modifying. |
Eh, I dunno. Especially as I'm yet to take my own head/barrel off the bottom end. All I have is two different sources saying that reboring sufficient to produce a 140~150cc cylinder at the end of it is possible but seriously runs the risk of either breaking into an oilway outright, or shaving its wall so thin that it's at risk of fatigue and perforation when the engine's in use. Coulda sworn that's what the liner was for anyway, but there you go.
Apparently one chap managed it, but it involved a bit of custom work basically welding up the hole so produced and reboring the oilway itself a couple millimetres offset from the original location. Erm!
With any luck once the bits are apart it won't be too difficult to actually see where the oil galleries actually run, and an informed judgement can be made on whether increasing the diameter by a good 5mm or more is a practical proposition.
It might even be that you could do a milder form of both, and that's what Honda actually did. EG take it up to about 133cc by boring out 2mm or so - therefore leaving an extra 1/8th inch of metal around any crucial features, and not necessarily having it 100% square vs the 125's position either - then increase the stroke by only 6mm instead of 9.5, giving a total capacity of 149.1cc.
Who knows though :p
The chinese ones just go big-bore and keep the stroke the same, but that requires widening the crankcase mouth by a few mm, and that's apparently a risk factor as well. Trying to find what any official version works out at is a hell of a game given the greater prevalence of the knockoff parts. The only ones I found so far that weren't, were Indian Hero Honda OHCs rather than OHVs; however these were a decidedly more square design, in fact slightly undersquare. The bore is still wider than on the CG125, but most of the improvement is in the stroke - it's in fact slightly more of a stroker than my back-of-the-beermat version described above.
| Quote: |
((DIY modifying the crank and conrod))
You might be able to move the crankpin out a bit, if it is a pressed together crank. |
'tis indeed so.
| Quote: | Easiest way would be to find a rod with a larger big end bearing and offset bore the crank webs out (VERY accurately) to take it. Depends how much meat there is on the crank webs as to whether you could get away with this. |
We'll have to see I guess. They look relatively substantial on the ebay pics, but one presumes Honda didn't really make them ever so oversized.
| Quote: |
Welding a rod together might survive long enough to set the idle speed if you were lucky! Put a spacer under the barrel and use the original rod. |
| teflon-mike wrote: |
((History of how modern reciprocating engine design came about and how connecting rods are made such to be suitably strong to handle their design torque and rpm)) |
Well that's me told, then. Things can't ever be simple, can they?
| Quote: |
((or maybe we just treat the bike like lego, to the contrary of most advice on that front ))
If you do get one to fit the crank and which is roughly the right length then it would be far easier to machine up a spacer to raise the barrel / machine off the bottom of the barrel to lower the barrel and keep compression about right. |
Seeing as gasket kits are pretty cheap, would it even be viable to just shove in an extra bottom gasket or three to raise it up by a suitable amount?
The problem then becomes, though, whether the (barrel mounted) cam follower will still follow the cam properly. Maybe need to space out the head instead? And then hope that the pushrods are long enough and the rockers have enough adjustment in them to cope? (Are replacement pushrods of arbitrary length hard to find/make?)
And then making sure the compression ratio isn't all to cock.
| Quote: |
Finding a suitable crank that could be modified to fit won't be easy. Unless you could salvage the crank webs and rod from something like an XL185 and press those onto CG crank end outers. |
I seem to remember the XL185 (and XR 185/200??) being mentioned somewhere in all this, so that might actually be the one I was thinking of all along.
124 / 49, x 58.5 = 148
184 / 148 = 1.243
1.243 x 124 = 154... hmm.
sqrt (154 / 124) = 1.114
1.114 x 56.5 = 63
(rounding errors give an actual engine size of 184.2cc)
So if the 185 has a 63mm bore... that may well be the crank & rod in question. Though unless the deck height is the same as the CG for some reason, it'll likely need a bit of spacing.
*googles*
Bingo. 63 x 57.8 ... which is actually shorter stroke than I thought, as it's actually only 180cc total. So, crap. That's only a 144cc result with the CG. Better than a slap in the face with a wet fish, but only 80% of the intended improvement. The numbers for the XR200 are either 56.5 or 57.8 depending on model, so it doesn't get any better that way. I guess the "147.9cc" result was therefore based off parts from a different machine entirely?
Still, I'd accept 144cc quite happily if it could actually be done. That's still +16%, so 12.5 instead of 10.8hp, and - theoretically speaking - an actual 70.0mph top speed.
And then the potential for overboring is a bit more realistic. That only needs to give a 3.5% increase in area, or a 1.7% increase in diameter to reach 149cc; 56.5mm up to 57.47mm. In other words, getting hold of a 1mm oversize piston kit (should hopefully be available?) and boring out the liner to suit, ending up with 149.1cc overall. Which matches nicely with Honda's already observed 0.9cc leeway (the CG is 124.1), and gives us very nearly 13.0hp theoretical (off by about 20 watts if we assume the CG is exactly 10.8), matching with that claimed by mysteriously delivered "CG 150" specs.
(And, one presumes, ~11.8Nm - or almost 11.5hp at 7000rpm)
(Yes, we could probably go bigger from here, but the idea behind this crazy exercise is improving the performance in a technically frugal sense; keeping it under 150.0 not only saves us from paying higher tax on something which may only be a few cc's over the limit with a meaninglessly small horsepower improvement vs what the first 25cc provides, but also saves us from knackering the fuel economy or reliability too badly).
And blah blah blah mumble mumble. |
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tahrey
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| Posted: 18:53 - 16 Oct 2012 Post subject: |
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It gets worse, this has set me off on one.
Additional project:
Get hold of the gearbox innards of a 6-speed XR somehow (or XL?)
Get hold of similar for another CG like mine
Put these gears on the shaft:
XR 1st (built in, most likely)
CG2
CG3
XR5
inverse CG3
inverse XR3
(as in, put the input shaft gear on the output and vice versa; there's half a chance they're interchangeable seeing as CG4 = inverse XR5, and CG5 = inverse XR4...)
And put sprockets on to suit in order to make 5th the max speed gear.
Ratio gaps generally tighter through the range, but with an overall wider spread. Nice low first and second gear for fast starts, even uphill, a good 5th for ultimate speed, and a cruising 6th that's not so high the bike can't do more than 55 flat out (in fact, the 125 should still be just-about good for 100.1 km/h)
Best shift points around 20, 31, 42 and 55mph, with an option on ~67 with a tailwind; gaps about 1.55, 1.35, 1.33, 1.22 and 1.10.
The gearbox it always should have had in the first place 
(ah balls ... I bet the output gears don't have dogs on them... even if they'd go on the shaft without argument... that screws that then. Tits.) |
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Kickstart
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| Posted: 00:13 - 17 Oct 2012 Post subject: |
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| tahrey wrote: |
OK? How so? (serious question)
Seeing as I've never really seen such things discussed before in this field. The first stage mods in terms of airways appear to be opening up the intake and exhaust systems to allow higher flow, but there's no discussion of actual "tuning" (like you would a musical instrument). |
Just opening up exhausts and using larger bore pipes will likely lose you a load of power on any vaguely performance bike (as said earlier, CG125 might not fall into this category). Same with any modern airbox, although single filters were a common mod when airbox designs were dire.
With exhausts they use the pressure wave hitting the end of the pipe and bouncing back to the exhaust valve, then back again just as the exhaust valve opens to suck out the next lot of burnt gas.
With intakes they do a similar thing with the length of the inlet to push air into the engine. Hence intake trumpets on old cars (which is what the airbox to carb connection works as), and on modern cars variable intake tracts varied with revs (not aware of any bikes using this track).
| tahrey wrote: | This is part of why I'm wondering if there would be any benefit in changing parts other than increasing the displacement. |
Good question. The CG cam setup is a masterpiece for cheap production and being tough, but not good for tuning. I do wonder if you could modify the cam follows to change the valve timing a bit.
| tahrey wrote: |
How's that for you? |
Try the Bikegraph link in my sig. Enables you to enter a torque graph and overlap that in each gear, along with a line for drag. Should enable you to have more idea about what gives you what and where.
| tahrey wrote: | For the 148cc re-stroke, take all given power/torque figures and multiply by 1.19, and all maximum speeds at particular rpms by 1.09, then consider those as the "best case", and adjust gearing to suit.
IE 65 top speed increases to 70, maybe 71. Lengthen that to 72~73 if we assume the regearing itself gives the bike a new top speed in the 66~68mph range.
61 max at peak torque increases to 66~67 itself.
And you'd even see nearly 55mph at 5250rpm, if you went crazy with the gears.
More realistically, that means there'd be plenty in reserve at, say, 57 and 43 with those rpms when re-gearing for 69 @ 8500 / 71 @ 8750 / 73 @ 9000 and an assumed typical Vmax of 70.0 with the engine favouring slightly lower rpms after the change) |
IF you can stroke it, then you might well gain might range torque but not much top end. Valve sizes and timing might well be the limiting factor, and stroking it to gain ~20% capacity increase is a hell of an increase in stroke. If we assume a standard rev limit of 10k (a bit low, but close enough and a nice round number to make the maths simple), that gives a mean piston speed of 16.5m/s. You would have about the same mean piston speed at about 8300rpm (if my maths is right - wouldn't guarantee it with this).
| tahrey wrote: | Eh, I dunno. Especially as I'm yet to take my own head/barrel off the bottom end. All I have is two different sources saying that reboring sufficient to produce a 140~150cc cylinder at the end of it is possible but seriously runs the risk of either breaking into an oilway outright, or shaving its wall so thin that it's at risk of fatigue and perforation when the engine's in use. Coulda sworn that's what the liner was for anyway, but there you go. |
My thinking is that the oil way is probably a simple drilling (straight, no point in doing anything fancy in something designed to be cheap to build), or possibly up the barrel studs. And again it wouldn't make financial sense to have to cast and machine these differently when building slightly different versions.
The liner getting rather thin wouldn't surprise me in the slightest though.
| tahrey wrote: | It might even be that you could do a milder form of both, and that's what Honda actually did. EG take it up to about 133cc by boring out 2mm or so - therefore leaving an extra 1/8th inch of metal around any crucial features, and not necessarily having it 100% square vs the 125's position either - then increase the stroke by only 6mm instead of 9.5, giving a total capacity of 149.1cc.
Who knows though :p |
As I have said, stretching the stroke will likely be FAR harder than boring it out. Unless you can get a suitable crank it is probably not viable. Also if the engine is stroked much of the extra stress will be on the crank and rod, which if they fail will likely make a lot more mess than a piston seizing.
| tahrey wrote: |
Seeing as gasket kits are pretty cheap, would it even be viable to just shove in an extra bottom gasket or three to raise it up by a suitable amount? |
Given you would need to raise the barrel 5mm or so, not really.
| tahrey wrote: | The problem then becomes, though, whether the (barrel mounted) cam follower will still follow the cam properly. Maybe need to space out the head instead? And then hope that the pushrods are long enough and the rockers have enough adjustment in them to cope? (Are replacement pushrods of arbitrary length hard to find/make?) |
Fair point, but longer push rods should be far easier to make than a longer rod
| tahrey wrote: | And then the potential for overboring is a bit more realistic. That only needs to give a 3.5% increase in area, or a 1.7% increase in diameter to reach 149cc; 56.5mm up to 57.47mm. In other words, getting hold of a 1mm oversize piston kit (should hopefully be available?) and boring out the liner to suit, ending up with 149.1cc overall. |
Think your figures are a bit out there. Using stock sizes, going from 56.5mm bore with 49.5mm stroke to a 57.5mm bore only gives you a capacity of about 128.5cc. Or have I misread you, and you are thinking of boring it out the small amount but using the longer stroke crank?
All the best
Keith
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karthead
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tahrey
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| Posted: 15:27 - 17 Oct 2012 Post subject: |
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Right I'll try to keep this one a lot shorter. Esp as I have things to do elsewhere!
| Kickstart wrote: |
Just opening up exhausts and using larger bore pipes will likely lose you a load of power on any vaguely performance bike (as said earlier, CG125 might not fall into this category). Same with any modern airbox, although single filters were a common mod when airbox designs were dire. |
Pretty sure my airbox design IS dire
Seen at least a couple of these with K&N's bodged on... though that might not actually make a short shit of difference.
| Quote: |
With exhausts they use the pressure wave hitting the end of the pipe and bouncing back to the exhaust valve, then back again just as the exhaust valve opens to suck out the next lot of burnt gas. |
Ah... ok then ... I thought that was 2-stroke only, as they tend to need a helping hand with scavenging? Hence the narrow power bands?
| Quote: | With intakes they do a similar thing with the length of the inlet to push air into the engine. Hence intake trumpets on old cars (which is what the airbox to carb connection works as), and on modern cars variable intake tracts varied with revs (not aware of any bikes using this track). |
Oho... ok... -actual- tuning then.
Strange how a lot of that seems to then just get tossed out the window when people start "tuning" their engines though? And it all still appears to work? 
| Quote: |
Try the Bikegraph link in my sig. Enables you to enter a torque graph and overlap that in each gear, along with a line for drag. Should enable you to have more idea about what gives you what and where. |
I think I might have had a play with that before, or something very similar. Thanks for the offer, I might have a look, but I've drawn enough of my own before. And I really am only estimating, and erring on the side of higher drag than is likely the reality, to stop myself over-gearing it.
| Quote: |
IF you can stroke it, then you might well gain mid range torque but not much top end. Valve sizes and timing might well be the limiting factor, and stroking it to gain ~20% capacity increase is a hell of an increase in stroke. |
It's starting to look that way
It just seemed like the easier, lower risk option at first.
| Quote: | If we assume a standard rev limit of 10k (a bit low, but close enough and a nice round number to make the maths simple), that gives a mean piston speed of 16.5m/s. You would have about the same mean piston speed at about 8300rpm (if my maths is right - wouldn't guarantee it with this). |
Which is only 37mph if I'm calculating it properly? Erm. I don't know what I'm supposed to take from this. In any case, the engine can presumably handle 10500~11000rpm (as this is about where the limiter is) but I don't intend to take it much beyond 9000 should I be able to do any of this work, so hopefully it shouldn't be too much of a stress on the thing.
| Quote: |
My thinking is that the oil way is probably a simple drilling (straight, no point in doing anything fancy in something designed to be cheap to build), or possibly up the barrel studs. |
It seems to be a bit half and half now I've finally got it apart, though I haven't had opportunity to study it in any detail.
| Quote: |
The liner getting rather thin wouldn't surprise me in the slightest though. |
The liner looks to be about 2mm thick, though I haven't any calipers to put on it and check (maybe use a ruler at the top end?), and it thins almost to a point at the bottom.
So I guess I can bore it out by 1mm (or 2mm if we're measuring diameter?) and still have a reasonable amount of it left?
| Quote: |
((using gaskets as spacers))
Given you would need to raise the barrel 5mm or so, not really. |
So it'd need to be a solid lump of metal, maybe with a gasket each side for sealing?
| Quote: | but longer push rods should be far easier to make than a longer rod |
They do look rather simple now I've got them out, but the limits of my re-engineering capability would either be to get pre-made ones that match requirements, or have some small engineering firm stretch / extend them somehow.
| Quote: | | tahrey wrote: | And then the potential for overboring is a bit more realistic. That only needs to give a 3.5% increase in area, or a 1.7% increase in diameter to reach 149cc; 56.5mm up to 57.47mm. In other words, getting hold of a 1mm oversize piston kit (should hopefully be available?) and boring out the liner to suit, ending up with 149.1cc overall. |
Think your figures are a bit out there. Using stock sizes, going from 56.5mm bore with 49.5mm stroke to a 57.5mm bore only gives you a capacity of about 128.5cc. Or have I misread you, and you are thinking of boring it out the small amount but using the longer stroke crank? |
1mm bore increase; 124.1 divided by 56.5-squared, multiplied by 57.5-squared = 128.5cc ... indeed.
However, I was starting from 144cc, having put in the XL185 crank and rod. 144 / (56.5)^2, x (57.5)^2 = 149.1cc
DONE O_O |
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| tahrey |
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tahrey
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Teflon-Mike
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Old Thread Alert!
The last post was made 11 years, 183 days ago. Instead of replying here, would creating a new thread be more useful? |
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