In going to list a few situations below that have happened to me, interested to know if its a problem with the bike or a user error:
Shifting from 1st to 2nd:
Regularly hits neutral unless accelerating hard, ie if I'm cruising along in first and think I'd be better in second it always goes to neutral but if I accelerate from some lights it goes straight in.
Sometimes after getting it in 2nd a few seconds later it will drop into neutral.
Sometimes when I've hit neutral or it drops into neutral I will pull the clutch all the way in and the throttle closed and when I try and change up the gearbox makes a sort of grinding noise and takes a few attempts to clunk in. (This happens on much fewer occasions than the above two)
Other gears:
Yesterday the bike randomly downshifted on me, I think it was 3rd to 2nd but I was ride along and suddenly it downshifted,
My foot wasn't in a position to downshift (intact I think it was still under the lever from my up shift as I was going from a 40 to a 70 so was expecting more up shifts)

you could be looking at the classic symptoms of worn dogs...

Might be also a touch of lazyness and you not getting the gear home..but if you are a touch slack and the dogs a touch worn..then you'll get gears jumping out.

I reckon dogs...

Gear issues can be caused by badly adjusted chain, worn clutch (plates and/or basket), gear selector spring / star and wrong oil, badly adjusted gear pedal too, but jumping out of 2nd is the classic sign of a thrashed and abused gearbox.

So if everythin obvious and simple is ok then its most likely worn dogs on the gear.

It usualyl slips under load though not from normal changing, you seem to have the opposite effect so check all the simple stuff again.

If it is the gear then only way to fix it is strip the motor down and replace the gears. Expesnive and takes time if you can get the parts. Often not knackered motor is cheaper. Cost can be offset by stripping and selling exisint motor after trnslaplant.

Mine did this for a bit, just kick it in harder.

Well it's been fine today, changing really nice and easy :s ill keep an eye on it and see if its something in doing, will check the chain etc. at the weekend. Thanks for the advice so far :)

mine was missing gears also ( nc30) so I adjusted the gear lever down about 10mm/15mm and its lots lots better.try the lever adjustment first benny.

weirdomagnet wrote:mine was missing gears also ( nc30) so I adjusted the gear lever down about 10mm/15mm and its lots lots better.try the lever adjustment first benny.

I actually though about this before, totally forgot to do it! Thanks for the help

Also make sure that the gear change link is at the correct spot on the gear output shaft spline.

There's a mark punched into each part, make sure they line up.

Cammo wrote:Also make sure that the gear change link is at the correct spot on the gear output shaft spline.

There's a mark punched into each part, make sure they line up.

I'll use my Haynes manual to translate that

look closely at the shaft and the gear linkage bit they have dots on them. line them up