Bike jolts round over 5,000rpm in second

[CookMySock]

Ok I'm looking at buying a bike, on the basis I can fix this problem. It's a '92 ZZR 400 with about 40,000kms and it starts jolting around over 4,500rpm only in second gear.

Any suggestions?

Many TIA,
Steve

[mattian]

worn teeth on the sprocket?? sounds like it might be jumping a tooth or 2

[merv]

Unless its actually lost some teeth off second in the gearbox.

[sinfull]

Define jolting a bit better Steve

[CookMySock]

Define jolting a bit better Steve

Actually I do not know mate.

This is the description I was given. The bike is 4 hours drive from me so I have never seen it.

It sounds like its gearbox related (only happens in 2nd.) It doesn't jump between other gears. Sounds to me like it disengages 2nd for a split second and re-engages with a clunk.

I am hoping that this is a very common symptom of something, perhaps a worn 2nd gear dog or selector. Common perhaps on bikes used for slow speed commuting.

I have asked him whether it started doing it suddenly.

If it's an easy fix I will take it on, or else its not worth it.

Steve

[Madmax]

sounds like more than one tooth missing off second gear
one tooth would only make a clicking noise