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Athenry
5th August 2014, 15:39
Hey there, not a Kiwi, but for some reason you guys seem to have a lot of GN250s, so this seems to be the best place for me to get advice.

Anyway, I bought an '82 GN250 last week, it's my first bike, before I bought it I didn't know the first thing about them. And I'm still piecing things together.

Over the past week I've taken a few bits and pieces off, polished everything up and repainted the frame - the surface rust was a nightmare.

At the moment I would like to adjust my suspension. But as I said - I don't know a thing about it. Are the front forks adjustable? The rear? Who knows.

Ideally I'd like to extend the front and drop the rear for now, I'd like to see what that looks like at least. How would I go about doing that?

Also, I'm considering wrapping the headers, because as far as I can see, it is damn impossible to get the things off (bolts are rusted in, and too tight for a mere mortal). The rust is caked on to the headers, as it seems to be will all older bikes. But the more concerning feature is the 1" diameter hole where the headers slide into the muffler, so I'd like to cover that up too. Would that work for now, or should I find a way to replace them?

ducatilover
5th August 2014, 20:26
Rear shocks are adjustable.
Front is not.
GNs are mega gay

mossy1200
5th August 2014, 20:30
, so this seems to be the best place for me to get advice.





This thread will provide laughs.

FJRider
5th August 2014, 20:58
On an '82 GN250 ... front suspension is not adjustable. The rear suspension may have some adjustment. Amount of noticeable change to that adjustment ... is for you to determine ...

Wrapping the exhaust will not enhance any performance (for want of a better word) your GN already delivers .. But it will lighten your wallet. It that is the "Look" you want ... go for it. It's only (your) money.

To extend the front ... options aren't freely available ... cheaply. To lower the rear ... a hardtail setup may be the go. Compared to what you'll have now ... the change will hardly be noticeable.

It's a old GN250 ... ride it 'till it dies ... then ditch it. (a big cliff or a big hole)

AllanB
5th August 2014, 21:31
Rear end - I'd be inclined to measure the mounts (holes?) and distance between and search E-bay Aussie for something with the same sized holes that are shorter eye to eye. You could always sleeve the holes if the replacements are oversize.

Forks ..... non adjustable so you revert to 1982 solutions - change the fork oil for a heavier weight - it will be like black water in there now. You could add a suitable packer in the top of the fork on top of the spring to take up the slop in the old springs. Various solutions worked from plastic pipe to my preferred of light wall steel pipe. Experiment with the length of pipe. I've not pulled a GN fork apart - there may be a factory spacer in their now - if so try 50mm longer.

This is all 'garage' adjustment for a very basic set of forks, tried and true old school stuff but I take no responsibility for your ability to comprehend or apply it or the result.

koba
5th August 2014, 21:39
Best thing I've seen done with a GN is a set of knobblies and MX bars.

ducatilover
5th August 2014, 21:59
From memory if you rock any more than 25mm in a spring spacer on a GN you'll get spring binding.
The rear adjustment makes it uncomfortable, or flabby. Take yer pick

danw
6th August 2014, 20:05
I've had an '82 GN250 for three years now, and have put over 35,000kms on it.

I never wanted to get a GN; they're such hideous-looking things, with their broken-backbone look that is neither classic cafe, nor comfy cruiser, but the universe somehow conspired against me, so there it is. In my garage.

Now, I'm a 6ft-tall man, and these bikes were built for small Japanese women, so it's kinda cramped, but the best thing I did was put some clubman-style drop-bars on it. Handles so much better now that I'm actually putting some weight over the front wheel.

The front drum-brakes are borderline-suicidal in the wet.

I'm not sure why you'd want to raise the front; it's as high as a bus as it is!
I wanted to get the front down, but found that dropping the fork tubes through the trees messed with the rake enough to make the handling less-than-enjoyable.
I have the rear suspension adjusted to it's firmest setting, and find it just right.
All up, it seems that factory set-up generally works best, I'm afraid.

Anyway, I kinda like the bike now, and am in no hurry to replace it.

richisells
11th August 2014, 07:53
I've just finished doing my GN250 all bar putting knee pads on the tanks and numbers on the side covers and i don't think it looks too gay anymore!!, i jacked the back end up by 30mm and dropped the front by 30mm if i remember correctly and it seems to handle...... well like a GN really!!, in all honesty i haven't ridden it long enough to tell you one way or another but i will in a week!!


299872299873

awayatc
11th August 2014, 09:57
Never thought i would say good looking and GN in same sentence........

I stand corrected..........

That GN from richisells looks great....

Paul in NZ
11th August 2014, 11:02
I've just finished doing my GN250 all bar putting knee pads on the tanks and numbers on the side covers and i don't think it looks too gay anymore!!, i jacked the back end up by 30mm and dropped the front by 30mm if i remember correctly and it seems to handle...... well like a GN really!!, in all honesty i haven't ridden it long enough to tell you one way or another but i will in a week!!


299872299873

That looks pretty good mate - well done....

ducatilover
11th August 2014, 21:15
Proper cool man

Where'd you get the fork boots from? They're sexypants.

richisells
13th August 2014, 03:26
Thanks, the Forkboots came off Ebay from MTS motorsports (producer) if that means anything to you, when i say just finished i geuss i mean the first stage i have just boought s/s bolts to go in the motor and have just ordered a 23cm high mini ape hangar for it!! once those bits are done then it'll be finished well that is until i find an 18 inch rear wheel for it then the wheels will be stripped and painted black with vintage firestones put on it so i geuss finished is relative! lol.

sorry to thread highjack, Athenry, you could always try penetrating oil on those header bolts for a good week and then try and remove them with a pneumatic wrench, we have pneumatic battery powered drivers in the workshop and i'm sure they would work but i would definately soak them first the greatest fear would be snapping them ofcourse as thats then just misery!

when you say extend the front do you mean like as in longer forks?? what is your goal to bobber the bike? i'm geussingg if that's the case you'll need to find longer forks, the rear end will be easy enough to drop with shorter shocks if i remember right the standards are 33cm eye to eye if you dropped to 31 you will notice a mega drop with the rake on the rear shocks, i would do a mock up first with a scrap bit of flat bar. the hole in the header is probably weldable if you have enough patience to get the weld back to good metal, if you have enough length you could chop out the bad bit and slide the muffler onto the good bit but you would brobaly have to do something to the rear mount then, i looked for headers for my bike as well as the total pipe is fucked but all the guys over here want stupid money for bits on a bike that aint worth shit, Ii just patiently welded mine up, you could always weld a new bit of pipe into the holey bit as in a sleeve.