GN250 Custom Project FSM

**the oldstuff** · 10th January 2014, 19:10

Does make that little GN look cool, well done man. Proves there's no need to spend a fortune to have a neat looking bike.
Now just to find a bigger barrel and piston eh....

**ducatilover** · 10th January 2014, 19:52

Originally Posted by the oldstuff

Now just to find a bigger barrel and piston eh....

Cheap enough from the land of communism.

**kiwikk** · 11th January 2014, 19:39

Originally Posted by the oldstuff

Does make that little GN look cool, well done man. Proves there's no need to spend a fortune to have a neat looking bike.
Now just to find a bigger barrel and piston eh....

Cheers for that.
My boy's pretty taken with it. Wants to use it as an Auckland runaround (ideal as a street bike). Prefers it to his CBR125R pocket rocket!
It's probably about as far as I'll go with this project. Don't want to over-capitalise.
Also don't want to mess with the simple and reliable engine for minor performance increase.

I'm on the lookout for a new project bike to do similar things with.....only with a twin or 4 cyl, 250 to 500cc.

**kiwikk** · 12th January 2014, 13:50

Originally Posted by ducatilover

Cheap enough from the land of communism.

But this is a '92 Jap bike (apart from the aftermarket cheapo indicators which are Chinese. Two of which have already broken

)
I'll not be putting anything Chinese in this engine until their quality standards have improved considerably.
From what I've read about the CFMoto 650, this might be starting to happen.

**ducatilover** · 12th January 2014, 19:40

Originally Posted by kiwikk

But this is a '92 Jap bike (apart from the aftermarket cheapo indicators which are Chinese. Two of which have already broken

)
I'll not be putting anything Chinese in this engine until their quality standards have improved considerably.
From what I've read about the CFMoto 650, this might be starting to happen.

I've used plenty of Chinese gear on GNs and it's the same as the Jap gear. Exceptions made for "chrome" work

**kiwikk** · 13th February 2014, 19:16

Look out Aucklanders.....
'E only 'ad it ten minutes an' look what 'e did to the old girl

Ah well, I suppose it could've been worse. Pink or summit.
Apparently this is that black stuff that just peels of without damaging the original paintwork.
He's 'stoked' 'cos real bikers now acknowledge him on the road.

I only let him have it 'cos I've moved on to something lets say 'a little more appropriate for my age'.
Check it out: http://www.kiwibiker.co.nz/forums/sh...Mixed-Messages

PS. See that little CBR125R in the background ? that'll be up for sale shortly. Only 6000 kms on the clock. Stay tuned

**KIPS powervalve** · 21st November 2014, 21:27

Originally Posted by kiwikk

Bazinga!
My secret revealed:
Picture 1 = Before and after rear suspension height comparison. Looks better without shrouds but they'll be necessary later.
Picture 2 = Components left to right a) 35mm preloader fashioned from hardwood. Lightweight alloy turned billets would be preferrable.
b) 25mm long coupling nut with 10mm fine thread and 14mm flats. Rare as rocking horse shit, so I got them with normal thread pitch and recut using a 10mm fine thread tap. Not ideal so if you've got access to a lathe, make some. (my local bike engineer couldn't be bothered so he scared me off with high price)
c) 40mm of 10mm dia fine thread bolt with head cut off.
Picture 3 = Coupler on. (note use of ratchet straps as spring compressors)
Picture 4 = Preloader on. Essential to get the spring action back where it should be.
Picture 5 = Shroud on. It hides the woodwork.
Picture 6 = Putting top mount back on. (Careful releasing those ratchet straps, keep hands clear or they'll have you)

Also as I've mentioned in previous posts on this subject, the right rear footpeg and exhaust mount subframe will need gently bending outwards by 12mm to clear the now lowered swing arm. Oh and also the brake lever arm will need trimming and the back wheel will no longer clear the ground when on the centrestand and the sidestand will also struggle to reach the ground so it'll need some help.

Worth it?.....

I think so.

Worth it for sure.

Sorry for digging up an old thread, but how do you take the shock to bits in the first place? All components seem to be able to twist around each other without unscrewing. I'm also scared of blowing a hole in the roof with a spring or other hard object like I did changing fork seals on my old FZR

**cowpower** · 25th December 2014, 17:25

Sad this thread is dead!! I'm just a year behind the 8ball here.

Thanks for the pics and shocks info, though I'm also intruiged about the shocks.. will I need compression clamp things? Basically I know nothing cept how to undo bolts and shine the shit out of things. But I would like to get my bike to this point. Do I need much prac knowhow? Or can I learn it from a book?

I can vouch for the shitness of made in china.. got a 2005 GN250 to learn on and do up and the first apparent issue was the cheap tainted bolts and screws. Some rusted through so much I had to drill them out :/ anyway they've buffed up fine in a vinegar soak and if they do that rusting shit again I'll have to buy a few more bolts. Also the exhaust has rusted to shit, and it's not even 10 yrs old yet.

**unstuck** · 25th December 2014, 18:18

Originally Posted by cowpower

Do I need much prac knowhow? Or can I learn it from a book?

You can learn any way that suits your disposition, willingness to learn is the key.
Getting your hands dirty and having a go is the best way to learn for yourself. You can do eeeet.

**kiwikk** · 31st December 2014, 19:10

Originally Posted by KIPS powervalve

Worth it for sure.

Sorry for digging up an old thread, but how do you take the shock to bits in the first place? All components seem to be able to twist around each other without unscrewing. I'm also scared of blowing a hole in the roof with a spring or other hard object like I did changing fork seals on my old FZR

You need to get the spring compressed enough to slip a slim 14mm spanner between the top of the chrome shroud and the aluminium top mount.
You'll see that I used a couple of ratchet straps as a poor man's spring compressor.
The chrome shroud covers a lot of the spring coils so you'll really have to crank the straps down hard on the few coils available.
Jam a bar through the top mount eye for leverage and whack the spanner with a hammer.
Unscrew the top mount.
Release the strap ratchets in stages using a screwdriver and keep your hands clear. The spring shouldn't fly off anywhere.
If you do the mod like I did, putting it back together will be much easier due to increased spring length.
Good Luck

**kiwikk** · 31st December 2014, 19:27

Originally Posted by cowpower

Sad this thread is dead!! I'm just a year behind the 8ball here.

Thanks for the pics and shocks info, though I'm also intruiged about the shocks.. will I need compression clamp things? Basically I know nothing cept how to undo bolts and shine the shit out of things. But I would like to get my bike to this point. Do I need much prac knowhow? Or can I learn it from a book?

I can vouch for the shitness of made in china.. got a 2005 GN250 to learn on and do up and the first apparent issue was the cheap tainted bolts and screws. Some rusted through so much I had to drill them out :/ anyway they've buffed up fine in a vinegar soak and if they do that rusting shit again I'll have to buy a few more bolts. Also the exhaust has rusted to shit, and it's not even 10 yrs old yet.

Spring compression clamps are the correct and safest tool but they cost and the chrome shroud might actually get in the way. We poor men make do with ratcheting tie-down straps. Just need to make sure they're not frayed. Operate on one spring at a time using two straps and crank them down evenly and enough to get a spanner between the shroud and the aluminium top mount flange.
Even if you don't do the lengthening mod, Losing the shroud looks good (if you can get the top coils clear of rust that is)

Can't emphasise this enough but keep hands clear when finally releasing the strap ratchets.

Good Luck

PS. I'm actually selling my old girl if you're interested: http://www.trademe.co.nz/Browse/List...x?id=827106450

**cowpower** · 12th January 2015, 22:19

Did you end up selling it outside of trademe or still have it? I'm tempted to sell my chinese $#@%^% and "upgrade" to something like a non chinese GN to tinker with further..

I've done a few exterior mods - new front indicators, have LED rear tail lights and indicators coming, and was thinking about replacing the exhaust - its got a bit of stubborn surface rust and a bit of a dent on the inside. Plus it sounds dumb. However my main goal is to get at least what I paid for it back so I don't think it's worth it? Still thinking of taking the shocks and forks apart though. Mainly to clean it up for sale - its 2005 so the chinese crap metal has already passed its best before. I bought it pretty much swimming in superficial surface rust!