Hi, I'm new to trials and have recently bought an 04 125. My query is, do they suffer from a noisy top end.

It was bought from a guy who is a qualified bike mechanic. He stated that it had recently had a top end rebuild with new small ends and rings, which I have no reason to disbelieve, as he showed me the old ones. But it has a rattle. Most noticeable at low revs/ tickover.

I was told they all sound like this.

Is this the case or do I need to consider pulling it apart to check.

Any help or advice would be much appreciated.

Thanks, Pete

I believe they tend to be a bit rattly, however I have to listen first hand to evaluate. Rings will not totally refresh one, requires a piston and a replate of the cyl in most cases. Then they are pretty quiet till they wear in a bit with use..

Hi Pete, I had a Sherco 07 125, new rings new bottom end. Still rattled, ran faultless for the two years I had it, I was told that's the way they are. I got sick of comments like "sewing machine" and traded up. Cheers Taff.

What 2T oil are you using and what ratio?

Is rattle worse hot or cold or does it reduce when you pull the clutch in?

Thanks for the replies.

There's no evidence of piston slap noise and appears to have plenty of compression, although I haven't tested it. Although I take your point that if the bore is worn simply fitting new rings won't correct the issue.

Oil ratio and type that it is running on is unknown as it had a full tank and I haven't had to fill it yet as iv'e only been out on it once.

I have mixed some fresh fuel at the ratio stated in owners manual at 2% with Putoline 2T trial.

It doesn't appear to be clutch related, as I am well aware of this, due to owning an R6. (Yamaha tick as its commonly known).

Not really sure if its worse when hot or cold. I'll check this out tomorrow when I use it next.

It sounds more like small ends in my opinion.

I think I will use it as is for a while, if it gets worse I will strip the top end and investigate.

Any further advice regarding this particular bike would be much appreciated.

Many thanks, Pete