GN 250 - Touring Project

[smegballs]

I used this handy chart from https://www.vintagebrake.com/mastercylinder.htm to help me select the master cylinder size.

https://i.imgur.com/tSxDYdn.png

https://www.customfighters.com/forums/showthread.php?t=56704
https://www.vintagebrake.com/mastercylinder.htm

Both seem to say that a ratio of around 12- 14/15 is what you want to aim for.

Red on the chart is the stock setup: 14mm M/c with single 38mm piston.

Green is the new setup with 11mm M/c a much healtier ratio of 11.9 rather than the poor stock 7.37.

The new M/c appears to be a brembo, I was expecting a nissin tbh on a jap bike but maybe they are putting brembo's on the r125's? Second hand part from ebay. If it really is a big problem, I'll go one size up to a 12mm M/c and see how that gets on, but IMO the brakes are really good as they are now.

I hit reserve for the first time yesterday and worked out my mpg for the first time. 63mpg for town riding on the gas a lot. I reckon 70+ should be easily achievable on a long 50/55 mph cruise.

I plan to ride it up to the BCF BBQ (then up to see a mate in coventry) so it will have a little uk run around before overseas adventures.

[i.p.phrealy]

If you see your mate in Cov on a Tuesday, get up to Bassett's Pole.
____________________
it is impossible to lick your own elbow...
and if you just tried you need professional help.
Finally allowed a big bike 19/03/14!

[smegballs]

Made a bit more progress today, with the end result the bike will be unrideable until tomorrow

Here's the wheel bearings, look like OE, one is nice and clean, one has got a load of shit/grit around it, but both turn freely without play atm.

https://i.imgur.com/Plem0gyl.jpg
https://i.imgur.com/0RDneFxl.jpg

Like Tef predicted, a fair bit of rust once the tyre comes off. The front has a slow punture, which is might just have something to do with this.....
https://i.imgur.com/DAa267nl.jpg

So bike is off the road until I get a new tube tomorrow. Also moar rustiness:
https://i.imgur.com/I2p2QzYl.jpg
https://i.imgur.com/far9UTRl.jpg

It's actually not too bad, mainly surface rust which is coming off with a wire brush okay. Gonna pick up some rattlecan black, new tube and rimtape tomorrow and hopefully get it all put back together. Then the with a bit of grease on the spindle, it should all come apart easy in future if it needs to.

Got a new tyre on order from demon tweeks for the rear, Michelin M45. I'll probably keep the catspaw stylee tyre on the front for the time being, but the rear is visibly old and cracked as feels very squiggly over white lines or cracks in the road. Rear is 4.60-16 so I've got a 110/90R16 which should fit fine, again new tubes and rimtape to go in on the rear for peace of mind.

Here is how it sits at the end of today. Got the gaiters on the forks, with a little rub of silicon grease on the stanchions under them. Fork seals look in good nick with signs of any leakage.

https://i.imgur.com/busPLPbl.jpg

[Teflon-Mike]

I wouldn't bother rattle-canning the rims.
Thin coat of pain will come off soon as you spoon new tyres on, do a few miles, exposing chrome beneath.
I would;
1) clean up with wire brush the spokes, spoke nipples and rim channel.
2) oil the spokes.
3) oil the spoke nipples; loose grease the rim/niple seats, tension nipples. Then dress ends of spokes.
4) Rather than painting whole wheel; I'd use chain-lube or wax-oil in the rim channel to protect the inside.
5) polish up the chrome as best as. It dont look too bad in pics, and a little surface rust on chrome, to my eyes is much less offensive asthetically than flaked off paint, 'cos it dont like to key to chrome, unless you grind it back.
____________________
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?'

[Tristan.]

Do drop by when your visiting your friend in cov.

[sabian92]

Watching with interest; touring on small bikes is brilliant

[pepperami]

What Sabian92 said +1
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I am the sum total of my own existence, what went before makes me who I am now!

[smegballs]

Well managed to get new innard-tubes and rim tapes on the front. Old man was meant to bring me a tin of waxoyl over but forgot, so they have just receiver a good wire brushing and a scrape to remove the crusts of rust. At least it is rideable now so I have transport again.

New rear tyre should arrive tomorrow.

[smegballs]

Well some progress has been made in the last week or so since I updated this thread.

Two new tyres (Micheline M45's) and Conti tubes have been fitted: whitelining is much reduced grip feels really confident for such cheap tyres.

Got a 12mm grimeca master cylinder off ebay for a fiver delivered, so I'm going to fit that and see it improves the back-to-the-bar quality that the 11mm master has.

Spend a few hours stripping connector blocks and bullet connectors, cleaning them up with wet and dry before re-assembling with a nice coating of silicon grease to dissuade future corrosion.

Check valve clearances, all were in spec bar one exhaust valve. I've noted all the clearances so I can see which way they have drifted next check.

Mudguards both removed, wirebrushed and given a good dose of red oxide followed by matt black. I expect to have the paint peel from the chrome but should help seal the underside.

Actually in general the matt black demon has attacked the bike......

I'll get up some pics tomorrow.

[TUG]

Nice to see an update in here, My ER5 thread is going a bit slow but once Uni is out the way I should be ok, ideally I want to strip it down towards the end of summer and spray it all up, but I need rid of the oil leak and MOT it first!
____________________
Haz ER-5, innit!

[stevo as b4]

Stick with this mate! Has lots of potential for looking damn cool with the right mods!

[smegballs]

I'm starting to have visions of twin headlights mounted to the machine.

Obviously I'm a little limited on overall electrical load, but with the leds replacing lots of the stock bulbs I reckon I should be able to run a single 55/60w headlight okay. Or more light overall maybe with twin headlights each with a 35/35w halogen in them?? Maybe even one normal bulbed headlight and one with these new H4 led bulb contraptions?

Last few days in the sun I've actually been out riding it a lot, as opposed to just molesting it. It's actually really fun to rag around town. New tyres feel nice and secure, mx bars give loads of leverage when steering and I've been filtering like a boss. Quite impressed with the little bugger

[Teflon-Mike]

HID.
35w. chucks out 10x the lumins and draws half the current.
And check part numbers, 'cos if that GN uses same 7" lense as the GS500E, the silverings not shot and the lens not etched, then its a damn good lamp, and any after-market set up you replace it with likely to be not half as good.
Honestly; I did a load of almost back2back lighting comparisons on the Super-Dreams, and the OE Stanley lenses were by far the best, whatever bulb you put behind them; swapped for 7" round, i tried a couple of after-market ones I had knocking about, and a Hella Sealed beam conversion for a Lucas 7", and an OEM GS500 lamp Snowie was given, again, proved tops; and fitted with high quality solenoid dipped HID was bludy brilliant!
When we went over to the Vic in Coalville with Smiler, I lead in the Chavic, Smiler followed on his CG, the glow worm in his headlamp just about lighting my back number-plate; Snowie on the Pup, hanging back a bit... well she didn't want to accidentally run over him, did she?.... but HID in GS lamp right at the back, on unlit country roads, on dip-beam was lighting road ahead of my car lamps!

Though current 'project' is to find a shell that will properly take a Lucas 7" sealed beam; as I have a pair of clear 'reflector' lenses, and HID's to go in them, that are supposed to be even better, I would like to try.

Quality over quantity; one big lens is worth more than a pair of little ones, and one good, big lens worth more than anything. Lens quality is far more important than bulb power. You can have a 250w flood-light bulb in there if you want, and wont do any good if most of it is wasted not getting chucked out the lap in the right direction to light what you need, or worse, casting harsh shadows and bright spots making it harder to actually interpret what's being lit up for you.
____________________
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?'

[smegballs]

My main issue with the headlight is bulb compatibility. Currently it is a weird thing that looks like this:

https://i.ebayimg.com/t/Motorcycle-Headlight-3-LUG-Bulb-12v-35-35w-/08/!B,q8JcgBGk~$(KGrHgoOKiMEjlLmV6SyBKsi71Q6TQ~~_12.JPG

Obviously a headlight that uses normal car H4's is far mopre useful in terms of getting replacement bulbs out on the road.

[TUG]

If you can go HID, go HID for sure. That reminds me, I might do that to mine!
____________________
Haz ER-5, innit!

[smegballs]

Will the drop-in HIDs pass and mot?

I've heard that putting a drop-in HID kit into a normal glass reflector headlight means that kittens get massacred by the score, the north pole melts and the polar bears drown while schoolbuses full of disable kids burst into flames across the country.

[sabian92]

[Teflon-Mike]

[smegballs]

https://i.imgur.com/sjcEVRE.jpg
https://i.imgur.com/4Nl9Y2e.jpg

Here it is so far.

I want to matt black it with a red oxide tank so bad

[slowlydoesit]

[trevor saxe-coburg-gotha]

[smegballs]

[slowlydoesit]

[smegballs]

Right, well I got out there and shimmed up the tank with bits of wood to get a feel for how it looks at different levels.

https://i.imgur.com/kajyr6B.jpg
https://i.imgur.com/c1VH9hX.jpg
https://i.imgur.com/eCu0IXo.jpg
https://i.imgur.com/6uRvYp7.jpg

For the last pic, use some imagination and pretend the line of the seat runs from the back over the trousers to make a more or less straight line. I think that it would already make the bike much less ghey and cooler looking already.

Problem is when jacked up by two spacers, the front of the tank fouls the bars. which isn't great and would need the tank to be dented in (in a somewhat controlled manner) or more material welded on the stops (which I don't really want on a commuter).

What do y'all think?

[smegballs]

Photoshop mockups.

https://i.imgur.com/zYCIQWk.jpg
https://i.imgur.com/RhUPT6A.jpg