Here's what to look for in a four-stroke cylinder with excessive piston wear.

The two-strokes have the same problem with excessive piston wear damage, but they tend to

experience piston skirt collapse, usually on the rear part of the skirt.

Jon

i havnt had chance to strip engine but is there a good chance barrel is worn and theres a second hand one on ebay for

You will probably find it cheaper to have the cylinder relined than buy a new one. I used PJ Engineering (search them on Google) to reline my RTL cylinder and they did an excellent job.

You will probably find it cheaper to have the cylinder relined than buy a new one. I used PJ Engineering (search them on Google) to reline my RTL cylinder and they did an excellent job.

If you plan to keep the bike, I'd probably have your cylinder re-plated. You'll need a new piston to send with your cylinder, in most cases, and the piston skirt clearance spec.'s (undoubtedly available in the excellent Honda service manual) so they can diamond-hone to the final size.

If it's a company that does Trials cylinders they should know what to do, but some re-platers do not believe the clearances should be as tight as they are from the factory and will tend to hone to looser than should be. Tell then exactly what you need.

Jon

what sort of price is it for replating

what sort of price is it for replating

I've just phoned Paul at PJ today about fitting a CRF piston to the 4RT. The replating part of the job was