Resend my activation email : Register : Log in 
BCF: Bike Chat Forums


Do A2 restrictions Reduce torque?

Reply to topic
Bike Chat Forums Index -> The Workshop
View previous topic : View next topic  
Author Message

adengtg
Scooby Slapper



Joined: 02 Sep 2017
Karma :

PostPosted: 02:01 - 06 Aug 2018    Post subject: Do A2 restrictions Reduce torque? Reply with quote

If you were to get a fairly large CC bike such as a Cruiser with high torque but low hp restricted to A2. Would the torque actually be affected or just horsepower?

May sound stupid or be obvious but i honestly don't know and can't find a solid answer elsewhere.

Thanks for the help.




Just for the record, not considering getting a cruiser or anything of the sort, just wondering as all.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

barrkel
World Chat Champion



Joined: 30 Jul 2012
Karma :

PostPosted: 04:25 - 06 Aug 2018    Post subject: Reply with quote

A larger capacity low HP bike will normally have a flatter torque curve, so you'll have more usable power at lower revs, and yes, it'll feel like it has more torque. OTOH cruisers are often heavy, so that may blunt things.

Peak torque at the same gearing won't be any different for the same HP. But a flatter curve and the fact that gear ratios are fixed, and not continuous, means that available torque at any given speed is probably higher.
____________________
Bikes: S1000R, SH350; Exes: Vity 125, PS125, YBR125, ER6f, VFR800, Brutale 920, CB600F, SH300x4
Best road ever ridden: www.youtube.com/watch?v=s2MhNxUEYtQ
 Back to top
View user's profile Send private message You must be logged in to rate posts

arry
Super Spammer



Joined: 03 Jan 2009
Karma :

PostPosted: 07:59 - 06 Aug 2018    Post subject: Reply with quote

One is the opposite side of the equation to the other. If you still made the same torque at the same RPM then you'd have the same power.

HP = Torque x RPM ÷ 5252.

In short yes, it would be affected.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

barrkel
World Chat Champion



Joined: 30 Jul 2012
Karma :

PostPosted: 13:12 - 06 Aug 2018    Post subject: Reply with quote

arry wrote:
HP = Torque x RPM ÷ 5252.

Thing is, without a CVT gearbox, you don't get to choose optimal RPM for your max torque. Thus it's the torque curve which makes all the difference between two bikes with same peak HP.
____________________
Bikes: S1000R, SH350; Exes: Vity 125, PS125, YBR125, ER6f, VFR800, Brutale 920, CB600F, SH300x4
Best road ever ridden: www.youtube.com/watch?v=s2MhNxUEYtQ
 Back to top
View user's profile Send private message You must be logged in to rate posts

arry
Super Spammer



Joined: 03 Jan 2009
Karma :

PostPosted: 13:20 - 06 Aug 2018    Post subject: Reply with quote

barrkel wrote:
arry wrote:
HP = Torque x RPM ÷ 5252.

Thing is, without a CVT gearbox, you don't get to choose optimal RPM for your max torque. Thus it's the torque curve which makes all the difference between two bikes with same peak HP.


Torque curve versus Peak Torque absolutely it is (notwithstanding you have a gearbox of course). But how do you propose to limit peak power without limiting peak torque which was, as I saw it, the premise of the question?
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Teflon-Mike
tl;dr



Joined: 01 Jun 2010
Karma :

PostPosted: 16:17 - 06 Aug 2018    Post subject: Reply with quote

Power is torque x revs, so the two are inextricably proportional... b-u-t... expand the equation, you get, Power = Cylinder Pressure x Capacity x Revs.... NOW...

How are you going to "restrict" power to licence limits... and remember, licence limits put a cap on 'peak' power... in theory if you were to fit a big enough super-charger you could cram enough 'charge' in the pot to make max permitted licence power at tick-over revs.... then use a blow-off valve to dump boost as revs rise to get not a 'flat' torque curve that would give a power curve rising with engine revs, but a falling torque curve, to keep the power at a flat maximum across rev range.... probably horrible to ride, but theoretically possible...

Practically; normally aspirated engine, the licence limited power is clipped at limit, by, conventionally a restriction washer or throttle stop choking flow of charge into the engine.

Theoretically these shouldn't stop the engine filling the cylinder at lower revs, so aught just clip the 'peak' off the power curve....

Practically? Charge flow is already starting to be choked at anything above peak torque.. So often works 'much' like the theory suggests, but an engine makes 'peak torque' when maximum cylinder filling occurs and you get most charge in the cylinder, hence the greatest cylinder pressure,

But where that is, depends on the state of tune of the engine. Peak-Torque is almost always at some revs lower than peak power. What's happening is that both torque and hence power increase with engine revs from idle, until 'optimal' flow is achieved, at peak-torque revs; Where maximum flow and hence cylinder fill is achieved; beyond that, the cylinder pressure starts to fall off, as the charge flow starts to fall away from optimal, BUT power usually still increases, as the extra revs allow more cycles to be achieved in the same time period, so smaller bangs but more often gives more power still, until peak power, where the flow capability of the engine fall off, and each cylinder fill is ever smaller and more smaller bangs don't make as much as fewer bigger ones.

On a more highly tuned engine, cam timing and port shapes tend to be optimized for peak flow; the cam timing tends to have a lot more advance, opening the valves earlier on the intake, and holding them open longer in 'duration', before closing them again on the compression. Likewise, the exhaust valve tends to be opened earlier, held open longer and close later, giving rise to more over-lap. The port shapes meanwhile... tend to be fatter and shorter, an aid to high volume flow at higher speeds..... Lower tuned motors, tend to have a shorter rev range, with both peak torque and peak power much further apart in that range.

Eg: 3.5-Liter Range Rover, engine from memory, has an almost flat torque curve, I think it peaks around 2,500 revs if you can spot it! Peak power is aprox 4500rpm, the power graph holding that almost another 1000rpm before it starts stuttering.

An 1-liter R1 engine, probably makes about the same 'peak' power at something more like around 13,ooo rpm, peak torque about 10,ooo. And that's a reletively 'torquey' motor. Revs out about 1000 rpm over peak power, but that's only 1/15th of the rev range, compare to Buick 213 sub-small block, where the same revs are 1/6th! Similarly the proportions of the rev range twist tick-over and peak torque and twist that and peak power skew the spikes further up the rev range. Look at something like an R6, with an even higher state of tune, those proportions are even more exaggerated, displaying an evcen higher state of tune.

Oh-Kay.... Exhaust headers and inlet ports volumes; there's a guideline for port and header volume, I think that its that the exhaust header volume should be about equal to the cylinder displacement; inlet port volume, around 1/4 cylinder volume. Those 'Pipes' can be short and fat, or tall and thin, and have the same volume.

On a low state of tune engine, the ports and headers are likely to be long and thin, and result in a lower 'peak' flow rate, but a higher gas speed at lower revs, good for low and mid-range power. On a high tune engine, ports and headers tend to be short and fat, good for high peak flow rates, but tend to result in rather low gas speeds at lower revs.

Higher gas velocities though 'tend' to offer better 'inertial charging'... the gas has momentum when traveling faster, and doesn't like to stop or come back... so, big ports work best at higher revs, smaller ones best at lower ones....

NOW how are you going to 'restrict' your engine? How much power does it make, how much more than restriction limits might it make And what state of tune is it in to start with?

IF you have a highly tuned engine, that makes a lot more power than the restriction limit, its likely got large diameter ports and aggressive cam timing, and perhaps 3x the peak power of restriction limit.... If you choke the flow to limit power to 1/3 peak, the thing will probably NEVER get even close to optimal flow through the ports, and with such a low gas speed it will be choking flow and hence cylinder fill, possibly even below peak-torque revs... so, you will likely loose 'torque' in the low and mid-range, as well as at 'peak'.

If you have a low tuned engine, that makes not a lot more power than restriction limit; you need choke flow a lot less, and you might maintain most if not all the low range torque and power the engine may make, and only start to strangle it in the higher rev range up to peak.

SO... the answer is.......

It ALL depends!

But Power remains a function of torque... you cant restrict power without restricting torque.... one is straight multiple of the other.....

BUT what you are talking about as 'Torque' isn't really torque... its motive thrust.... how much 'shove' you get at the driven wheel, which is further a function of gearing, and also 'drag'... which doesn't actually change the 'shove' coming from the engine, but how much of it you experience..... A-N-D we are now in a very much more technical arena, where what you 'feel' as power and or 'torque' and many try and explain as power vs torque, isn't... its power delivery..

So... back to square one, really.... and does it really matter all that much?

The likely loss of low down 'thrust' on a 'mildly' restricted engine is likely fairly small, and on old 33bhp restriction, it was common for better restriction kits to come with a smaller gearbox sprocket to lower the overall drive ratio and get back the 'thrust' at the back wheel, and only clip the power peak and top speed.

But, how much the 'ride-ability' is effected, still depends on bike, and its state of tune to start with, how much it need be restricted by, and how that restriction is achieved, and whether the bike's re-optimized for that restriction, with alternative gearing if needs be, etc etc etc.

SO... how long's a piece of string question really.....
____________________
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?'
 Back to top
View user's profile Send private message Visit poster's website You must be logged in to rate posts

MCN
Super Spammer



Joined: 22 Jul 2015
Karma :

PostPosted: 18:03 - 06 Aug 2018    Post subject: Reply with quote

So is that a yes or a no?
____________________
Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Fin
World Chat Champion



Joined: 27 Feb 2016
Karma :

PostPosted: 19:49 - 06 Aug 2018    Post subject: Reply with quote

What about the few diesel bikes Tef?

How about tuning those?

Smile
 Back to top
View user's profile Send private message You must be logged in to rate posts

adengtg
Scooby Slapper



Joined: 02 Sep 2017
Karma :

PostPosted: 21:53 - 06 Aug 2018    Post subject: Reply with quote

arry wrote:
One is the opposite side of the equation to the other. If you still made the same torque at the same RPM then you'd have the same power.

HP = Torque x RPM ÷ 5252.

In short yes, it would be affected.


Right, i see.
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

adengtg
Scooby Slapper



Joined: 02 Sep 2017
Karma :

PostPosted: 22:04 - 06 Aug 2018    Post subject: Reply with quote

Teflon-Mike wrote:
Power is torque x revs, so the two are inextricably proportional... b-u-t... expand the equation, you get, Power = Cylinder Pressure x Capacity x Revs.... NOW...

How are you going to "restrict" power to licence limits... and remember, licence limits put a cap on 'peak' power... in theory if you were to fit a big enough super-charger you could cram enough 'charge' in the pot to make max permitted licence power at tick-over revs.... then use a blow-off valve to dump boost as revs rise to get not a 'flat' torque curve that would give a power curve rising with engine revs, but a falling torque curve, to keep the power at a flat maximum across rev range.... probably horrible to ride, but theoretically possible...

Practically; normally aspirated engine, the licence limited power is clipped at limit, by, conventionally a restriction washer or throttle stop choking flow of charge into the engine.

Theoretically these shouldn't stop the engine filling the cylinder at lower revs, so aught just clip the 'peak' off the power curve....

Practically? Charge flow is already starting to be choked at anything above peak torque.. So often works 'much' like the theory suggests, but an engine makes 'peak torque' when maximum cylinder filling occurs and you get most charge in the cylinder, hence the greatest cylinder pressure,

But where that is, depends on the state of tune of the engine. Peak-Torque is almost always at some revs lower than peak power. What's happening is that both torque and hence power increase with engine revs from idle, until 'optimal' flow is achieved, at peak-torque revs; Where maximum flow and hence cylinder fill is achieved; beyond that, the cylinder pressure starts to fall off, as the charge flow starts to fall away from optimal, BUT power usually still increases, as the extra revs allow more cycles to be achieved in the same time period, so smaller bangs but more often gives more power still, until peak power, where the flow capability of the engine fall off, and each cylinder fill is ever smaller and more smaller bangs don't make as much as fewer bigger ones.

On a more highly tuned engine, cam timing and port shapes tend to be optimized for peak flow; the cam timing tends to have a lot more advance, opening the valves earlier on the intake, and holding them open longer in 'duration', before closing them again on the compression. Likewise, the exhaust valve tends to be opened earlier, held open longer and close later, giving rise to more over-lap. The port shapes meanwhile... tend to be fatter and shorter, an aid to high volume flow at higher speeds..... Lower tuned motors, tend to have a shorter rev range, with both peak torque and peak power much further apart in that range.

Eg: 3.5-Liter Range Rover, engine from memory, has an almost flat torque curve, I think it peaks around 2,500 revs if you can spot it! Peak power is aprox 4500rpm, the power graph holding that almost another 1000rpm before it starts stuttering.

An 1-liter R1 engine, probably makes about the same 'peak' power at something more like around 13,ooo rpm, peak torque about 10,ooo. And that's a reletively 'torquey' motor. Revs out about 1000 rpm over peak power, but that's only 1/15th of the rev range, compare to Buick 213 sub-small block, where the same revs are 1/6th! Similarly the proportions of the rev range twist tick-over and peak torque and twist that and peak power skew the spikes further up the rev range. Look at something like an R6, with an even higher state of tune, those proportions are even more exaggerated, displaying an evcen higher state of tune.

Oh-Kay.... Exhaust headers and inlet ports volumes; there's a guideline for port and header volume, I think that its that the exhaust header volume should be about equal to the cylinder displacement; inlet port volume, around 1/4 cylinder volume. Those 'Pipes' can be short and fat, or tall and thin, and have the same volume.

On a low state of tune engine, the ports and headers are likely to be long and thin, and result in a lower 'peak' flow rate, but a higher gas speed at lower revs, good for low and mid-range power. On a high tune engine, ports and headers tend to be short and fat, good for high peak flow rates, but tend to result in rather low gas speeds at lower revs.

Higher gas velocities though 'tend' to offer better 'inertial charging'... the gas has momentum when traveling faster, and doesn't like to stop or come back... so, big ports work best at higher revs, smaller ones best at lower ones....

NOW how are you going to 'restrict' your engine? How much power does it make, how much more than restriction limits might it make And what state of tune is it in to start with?

IF you have a highly tuned engine, that makes a lot more power than the restriction limit, its likely got large diameter ports and aggressive cam timing, and perhaps 3x the peak power of restriction limit.... If you choke the flow to limit power to 1/3 peak, the thing will probably NEVER get even close to optimal flow through the ports, and with such a low gas speed it will be choking flow and hence cylinder fill, possibly even below peak-torque revs... so, you will likely loose 'torque' in the low and mid-range, as well as at 'peak'.

If you have a low tuned engine, that makes not a lot more power than restriction limit; you need choke flow a lot less, and you might maintain most if not all the low range torque and power the engine may make, and only start to strangle it in the higher rev range up to peak.

SO... the answer is.......

It ALL depends!

But Power remains a function of torque... you cant restrict power without restricting torque.... one is straight multiple of the other.....

BUT what you are talking about as 'Torque' isn't really torque... its motive thrust.... how much 'shove' you get at the driven wheel, which is further a function of gearing, and also 'drag'... which doesn't actually change the 'shove' coming from the engine, but how much of it you experience..... A-N-D we are now in a very much more technical arena, where what you 'feel' as power and or 'torque' and many try and explain as power vs torque, isn't... its power delivery..

So... back to square one, really.... and does it really matter all that much?

The likely loss of low down 'thrust' on a 'mildly' restricted engine is likely fairly small, and on old 33bhp restriction, it was common for better restriction kits to come with a smaller gearbox sprocket to lower the overall drive ratio and get back the 'thrust' at the back wheel, and only clip the power peak and top speed.

But, how much the 'ride-ability' is effected, still depends on bike, and its state of tune to start with, how much it need be restricted by, and how that restriction is achieved, and whether the bike's re-optimized for that restriction, with alternative gearing if needs be, etc etc etc.

SO... how long's a piece of string question really.....


Well, would there be any actual gain from riding a large cc bike on A2? A large cc bike that has been restricted compared to something like an Mt-03 which makes the A2 power naturally.

For example would a cb1100 making ≈88hp or similar commuter bike have better torque figures compared to a small(Aimed at A2) bike even though they both make the same HP after restrictions? Or would the added weight of a bigger engine counter-act any added performance.Again, this is just for example, i'm not on about actually buying a big cc bike or anything
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Teflon-Mike
tl;dr



Joined: 01 Jun 2010
Karma :

PostPosted: 09:45 - 07 Aug 2018    Post subject: Reply with quote

https://www.cycleworld.com/sites/cycleworld.com/files/styles/1000_1x_/public/import/embedded/wp-content/uploads/2013/07/Honda-CB1100-dyno-chart.jpg?itok=cOck05C-
CB1100 Power Graph (Unrestricted)Aprox 85ft-lb accross the rev range
https://www.cycleworld.com/sites/cycleworld.com/files/styles/1000_1x_/public/2016-yamaha-fz-07-dyno-chart.jpg?itok=qDSrJWn7&fc=50,50
MT03 Power Graph (Unrestricted) Aprox 45ft-lb accross the rev range.

Those power graphs are plotting Maximum power, Wide-Open-Trottlem under load at every crank rpm....

Remember, Power is Cylinder Pressure x Cylinder Displacement x crank-revs.... if you 'restrict' as oposed to de-tune, you 'clip' the torque curve at restricted power-peak, so it cant make any more power than that.

It's effectively like riding the same bike, but only able to half open the throttle.... ponder.

MT03 is reportedly a lively little thing, with wind in your face back to basics, lumpy twin, riding experience, a light 'chuckable' frame, and an overall 'Dynamic' riding sensation.

CB1100 weighs quarter of an effin ton FFS... do I need say much more? STABLE is a good word for it. Lazy, probably another.

Before you start you have bikes with very different charecters.

Would you notice the difference in a restricted CB1100 compared to an unrestricted MT03? Hmmmm...

The MTO3 would still be a seat of your pants 'dynamic' experience. The CB1100 would still be 'Lazy'.

How often does any-one ride anything 'Wide-Open-Throttle'? I often ride a 125 you have to thrash the pants off, its one of the few things I 'like' about it! Get on the 750 and open the taps all the way, and I'm breaking speed limits before I reach the top of the street (Actually, its a short street and only a 20-limit.. same could probably be said of the 125 akchul... but...) I very very seldom ride anything at wide-open-throttle very often, and if I do, not for very long.

The 125 tops out WOT about 70mph, so I 'may' if I took it up the motorway, hold it wide-open pretty much for-ever.. I dont, M-Ways is boring! On the 750... sustaining 70mph still only begs about 12bhp, so I can do that holding it maybe 1/8th throttle.

So, the extra power really only comes into play under acceleration... now that weight comes into the equation.....

CB1100 weighs quarter ton, MT03 barely 2/3 that, at 170Kg.. even before adding restrictions, the MT03 has an edge in power to weight ratio, and it's gearing is likely optimised for it, Restricted CB1100 is still lardy and lazy in comparison, and it's gearing probably isn't optimised for being castrated.

BUT would you notice?

Do you intend to put it up the drag strip?
Do you intend to take it round a race track?
Would you ever, in either circumstance go head to head with the other?

NO! is the short answer... if you know no different, you probably WOULDN'T notice any difference.

The difference would be there; BUT, that difference would be more to do with the different original characters of the bikes, NOT how they responded to whatever restriction you applied to them.

MT03, would as its designed be a rather lively, dynamic and spirtited little thing, delivering 'sensation' from wind in your face naked styling and lumpy twin-cylinder power delivery.

CB1100, would still be rather lardy and lazy, comfortable and stable, and rather unfussed, with very smooth engine, and all that mass damping a lot of sensation...

BOTH will get up to around 80-90mph... to risk your hard won licence... and blow your hat off....

At that sort of higher mortorway speed and above, the matter is becoming pretty accademic; three figure velocities on a naked bike can become very tiring very quickly.

45bhp will only just get you into those sort of teritories, and really it's all over by about 110 anyway... so just a matter of how quickly you get there, and in that?

Well, the CB1100 weighs quarter of an effin ton!

I keep stressing that... its actually as heavy as my old VF1000, and I rather liked that... it makes for stable predictable progress... hard work if you try chucking it about... but otherwise 'comfy'. VF's probably not a bad bench-mark to go by TBH, as stock it's quoted 115bhp is nothing so outragiouse these days.. still more than the CB11oo though....

Off the line? That extra pork takes some more welly to get shifting.... but in recompense, you would hope, and probably nievely, that it would also pin the back-wheel to the tarmac and give you traction to use it... in the case of the VF1000, in the era of cross-ply tyres, I can tell you quite emphatically... it doesn't!

Which begs suggestion that for all practical purposes, any extra beef that a restricted CB11 might have will be pretty small potatoes; it will need the extra to launch as briskly, and in that, how sticky the tyres how well set up the suspension, how bumpy the road, how much inate 'feel' the rider has, will make as much or more practical difference...

Go look at the different times for street-stock drag bikes; for all its easy to deride the sport as not requiring the skill to go round corners, there's still a huge difference in elapsed times of essentially identical bikes through the traps, with different set-ups and tyre pressures, as well as riders.

Point-to-Point on the road? Similar deal, and given the real-road risks, more will be down to rider bravery/stupidity as it ever is rider skill, and any of that more significant than brochure specs.

You pick an MT03 because its a good alrounder, a capable comuter, and that dynamic ride is a bit of fun on the back-lanes come the week-end.

You pick a CB1100 cos... its BIG... it's all about that muscle bike style, and a more laid back ride; and maybe cranking high miles in reletive comfort on a long week-end.

The charecter of the bike comes though in anticipated use, and likely reasons to buy.

If retro-style, and behemouth proportions, and a more 'relaxed' less press-on nature atract you... then get one! Its not about the 'performance'.... does seem a bit perverse to buy a 'Muscle-Bike' that actually doesn't have all that much muscle.... and just for comparison, Honda's own contenders in the Muscle-Bike era were the CBX1000, that only actually offered 105bhp, and the later and lighter CB900F, that offered 95... both still more than the CB11.... so its a 'Muscle-Bike' that actually doesn't have all that much muscle... before you clip its wings some! BUT, it's charecter isn't about the performance, its about the look and the lazy, which restricted it would still have....

It would ALSO still have the COST.... which takes topic off on another tangent.

Big Behemouths are expensive; and they are expensive to run. Back to that old VF of mine; book suggested it should return 30mpg.. which was pretty dire compared even to a 1.0 Fiesta of its own era, let alone a Citreon C3 of modern! But, I could easily see that halved, giving it some stick twixt traffic light GP's... or, on a Sunday-Run, doubled, touring the Cotswoulds.. but either way, I was lucky to get 2ooo miles from a back tyre, and I was paying a heck load in the insurance.

The more 'every-day' sensible MT03, without the pork, aught be a lot lighter on consumeables like tyres and chains and brake pads; however its ridden. Insurance is likely to be a lot more reasonable too, especially as you dont risk a 'loading; on that having to declare the 'mod' of restriction.... pay heed; you cant ride one 'standard' policy price will be calculated as standard, restriction then added as a 'mod' likely to put premium up, not down.

SO! If you are more concerned about performance; the MT03 depsite almost certainly having less 'low down' grunt, will still be the more dynamic and engaging of the two to ride; it will probably be easier to get off the line at a restpectable rate, and a lot less of a handful in the twisties; it also hasn't got such 'plush' suspension or engine from the go-get, it will almost certainly "Feel" the more lively of the two, whatever the specs might suggest.. if that's what floats your boat, get one of them!

The MT03, not needing restriction, and as a more sensibvle 'every-day' all-round bike, makes so much more sense on so many levels, where low-down-stomp, is but tiny tiny part of the overall equation.

Put it this way.... if I wanted as much 'fun' as I could get on an A2 licence... I would probably be looking to buy and properly revovate an old 125 2T like an Aprillia RS or Cagiva Mito... neither would likely scare even 30bhp let alone 45bhp, and might only 'just' nudge a genuine 100mph... but down a twisty country road, about as engaging a ride as I could find.. and conveniently not so excessive as to so seriousely threaten insta-ban territory.

If I wanted as much Sunday 'Cool' as I could get, for poppingt out to a bike meet, seeing the Cotswoulds, maybe heading to the algarve on a bank-holiday week-end; A-N-D I had the money to justify it... then a restricted CB1100 might make it onto the short list.... but there would be a heck of a lot on that short list above it, like a Moto-Guzzi Mille GT or chrome mudguard CB750-four, Meriden Triumph Bonaville T140... which begs some ponderation, because they are the real-deal 'classics' as oposed to modern era 'Retro's.. which is another subject, B-U-T;

A dozen years ago, I was tempted by a Kawasaki WR650, and the debate whether that was 'better' than the then pretty new, Hinkley Bonnaville. My conclusion THEN, was that for the money, the 'real-deal' of a Meriden T140, worked out the more sensible choice, and only got better as it got older; the contemprary 'Retros' just becoming old bikes with even older styling... the real-deal classic, like a fine-old wine, getting better with age, and the lack of depreciation, potential for actual apreciation offsetting so much of the higher maintenence demand they begged, and the old retro's would inevitrably... and on an A2, more genuine lassics are native A2 complient without restriction, if you can live with one.

Curiouse that even with a full RWYL'A' licence, my choices for sunny day pose machine, aren't actually a lot different than what I might put on the list with an A2.. top of the pops for that, though would probably be a Yamaha XJR1300, which is outside A2 restriction..

For an every-day all-round rider? Similar story TBH and the A2 vs RWYL'A' wouldn't make a big deal to the matter.

Every day rider is and has been for over a decade the faithful Honda CB seven-fifty... case in point for the 'Retro'... I bought it 'cos it was 'cheap' rather than a retro; now it's ironically older than the bikes it harps back to in style were when it was new, but its not a classic like they were, its just an old heap! At 75bhp and 205Kg its A2 restrictable, and a very useful all-rounder... for more every-day useable machine.. Oh-Kay 'Cheap' an older CB500 or ER5 would probably offer more bang for my buck; for something with a tad more style and spirtit an SV650, might tip the scales... twin cylinder simplicity rather off-set by water-cooled complexity and V-Engine inaccessibility.. actually lines up swings and roundabouts slose to the Seven-Fifty...

That MT03, though would take some beating as an all-round do it all package... whether A2 or not.. and on A2 and not having to satisfy an insurance companies demands to prove restriction; offers a lot of turn key low hassle motorcycling.

And as bench-mark, for an all-rounder, whether A2 or not... there would have to be some pretty spectacular reason for looking a lot further, and on A2, even more reason for whether rival might really offer them.

So short answer is, NO, really... withgout riding an unrestricted bike back to back with a restricted one, you wouldn't know much better or be disapointed by a restricted A2 bike, that much.... but whether the charecter of the machine suited, is another question, whether you could live with the usually added cost, another still, and over-all, the differences will be in that charecter match, NOT the brochure specs or how a washer up the chuff may effect them!

With MT 03 prices trending around the £3K mark... the financial insentive to get something bigger/more powerful and restrict, would be rather blunted.

Might offer some cash insentive if I were looking at £800 XJ600's and the like, or Kawasaki Zephyrs; but in that case, it would be a question of what came along at the right money, and what the devil in the detail was after I'd checked the price of new tyres, sprockets and done some insurance quote comparisons. I wouldn't be looking at a bigger restricted bike to offer me much if any more bang for my buck, I WOULD expect it likely to cost me more one way or another... and still the MT 03 would tend to present itself as a pretty tough to beat bench-mark.

Power, A2 restricted vs A2 standard, IS but a tiny fraction of the overall equation; it really isn't something that would make me look for or avoid a bike that had to be restricted... other than knowledge that a badly modded bikie, and a restriction IS a mod, remember, can be absolutely horrible... a good stocker might not be all that inspiring or exiting to talk about, but from lack of hassles, tends to offer the more thrills more often, 'just' doing what it was designed to.

So whats the 'real' question here?
____________________
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?'
 Back to top
View user's profile Send private message Visit poster's website You must be logged in to rate posts

Kentol750
World Chat Champion



Joined: 24 May 2016
Karma :

PostPosted: 10:40 - 07 Aug 2018    Post subject: Reply with quote

I think Teflon has explained it. You need to consider power to weight after restriction to get at what you're asking. But as it's all irrelevant anyway, so is calling a cb1100 a cruiser. Look at a vn900....280+ kilos!
____________________
Some bikes.
 Back to top
View user's profile Send private message You must be logged in to rate posts

adengtg
Scooby Slapper



Joined: 02 Sep 2017
Karma :

PostPosted: 13:49 - 07 Aug 2018    Post subject: Reply with quote

Kentol750 wrote:
I think Teflon has explained it. You need to consider power to weight after restriction to get at what you're asking. But as it's all irrelevant anyway, so is calling a cb1100 a cruiser. Look at a vn900....280+ kilos!


I wasnt calling the cb1100 a cruiser, the cruiser thing was just for an example of a type of bike which has low hp but high torque.But i do get the picture now
 Back to top
View user's profile Send private message Send e-mail You must be logged in to rate posts

Kentol750
World Chat Champion



Joined: 24 May 2016
Karma :

PostPosted: 21:16 - 07 Aug 2018    Post subject: Reply with quote

A bike that makes 47bhp as standard and weighs the minimum allowed to get an a2 ticket will be the best thing you can ever get. And reliable, reliable's good.
____________________
Some bikes.
 Back to top
View user's profile Send private message You must be logged in to rate posts
Old Thread Alert!

The last post was made 5 years, 234 days ago. Instead of replying here, would creating a new thread be more useful?
  Display posts from previous:   
This page may contain affiliate links, which means we may earn a small commission if a visitor clicks through and makes a purchase. By clicking on an affiliate link, you accept that third-party cookies will be set.

Post new topic   Reply to topic    Bike Chat Forums Index -> The Workshop All times are GMT + 1 Hour
Page 1 of 1

 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

Read the Terms of Use! - Powered by phpBB © phpBB Group
 

Debug Mode: ON - Server: birks (www) - Page Generation Time: 0.18 Sec - Server Load: 0.25 - MySQL Queries: 17 - Page Size: 115.59 Kb