Making a GN250 user friendly

[rogson]

I don't know whether these are common problems/irritations with the Chinese assembled GN250s, but if so this may help.

A friend recently bought his wife a 2005, 1 owner 5,000km GN250 to learn on. I offered to do a service/check-over and make any adjustments required. The bike is mint, but on riding it I noticed a couple of minor and one major irritations - which novices/learners certainly don't need.

Firstly, the clutch would not disengage completely. The adjuster on the handlebar lever was wound fully out, so in order to get it adjusted properly and to enable further adjustment at the handlebar lever (if/as the cable stretches) I moved the clutch actuating arm (on top of the crankcase) around one more notch on the spline.

Secondly, the front brake lever was very sensitive and had virtually no free-play before the brake came-on. To fix this I removed the lever and filed a bit off the nub that pushes on the piston of the master cylinder (increases the free-play). I also bent the end of lever a little toward the handlebar to reduce the reach. The brake now feels progressive and is easy to reach/apply.

The major issue was the cold starting/running and low-end performance. The bike was extremely cold-blooded, took an interminable time to warm-up and even when fully warm would bog on take-off or under acceleration if a healthy dose of throttle was used. After checking the air-intake/filter was as it should be, I took the tank off and checked the mixture screw (top front of carb under a rubber plug) to find it was less than 1/2 turn from fully closed. I rigged-up a temporay fuel line, ran the bike and adjusted the mixture screw for best idle. Best idle was at 4 turns-out! The bike now starts easily, warms-up quickly, idles smoothly and takes-off/accelerates cleanly.

I'm sure these issues were apparent when the bike was new (the original owner didn't even know the bike had a choke!). It seems to me they are all adjustments that can (should?) be made in a predelivery check, but I guess the dealers can't/don't spend a lot time on a $3,500 bike.

[Nagash]

+1 for posting this up.

But when you first get your bike setting it up to suit you is mandatory.

Ofcourse if it's your first bike you won't know how to do these things.. but it's good that you offered your services, which more people should do to beginner riders.

With the bike shop not setting it up correctly.. They ship those things in and out so quickly I'm not surprised they don't go beyond making sure the engine starts and the lights turn on..

[CB ARGH]

You sure worked your magic mate! +1

[Meekey_Mouse]

Hey, thanks for the info! My mate is lookin at gettin a newer GN, so this is very useful info

[NZDaniel]

I never had any of those problems on my GN250.

I do notice that the tires aren't particularly great for wet weather though watch out in the wet on a GN aye.

[twinkle]

The major issue was the cold starting/running and low-end performance. The bike was extremely cold-blooded, took an interminable time to warm-up and even when fully warm would bog on take-off or under acceleration if a healthy dose of throttle was used. After checking the air-intake/filter was as it should be, I took the tank off and checked the mixture screw (top front of carb under a rubber plug) to find it was less than 1/2 turn from fully closed. I rigged-up a temporay fuel line, ran the bike and adjusted the mixture screw for best idle. Best idle was at 4 turns-out! The bike now starts easily, warms-up quickly, idles smoothly and takes-off/accelerates cleanly.

Just a note, I bought a 2006 gn250 and the only outside adjustment for the carburettor was the idle mixture. Just in case somebody out there goes and starts unscrewing random things