Leatherat Posted September 10, 2010 Posted September 10, 2010 Any help appriecated. My 2000 XVS125 dragstar has just past the 10,000 mile marker and has developed a noise. The noise is pretty difficult to explain in words, but here goes...... It sounds like a high pitched Grrrrrrr almost like a chain hoist being pulled quickly, and rises and falls with the engine speed. Not so noticable when stood still, but on the road above say 30mph it builds to a disconcerting point, however it is dramatically reduced, to a stop when the clutch is pulled in. My thoughts are that the tappets (valve clearances) need adjustment, but hey what do I know! What are your thoughts? The bike has been regulary serviced by a Yamaha main dealer throughout its life, the only thing I did to it just before the noise started was I had a punture on the rear tyre, and obviously the drive chain had to be refitted. I think its the right tension, but if it were too tight might that cause the problem?
chris66 Posted September 10, 2010 Posted September 10, 2010 tight chain can cause a noise from the engine.does the bike do it when revved in neutral? chris
Paulwhite Posted September 10, 2010 Posted September 10, 2010 yeah chain is on too tight ! you will find that if you give it 1 inch slack then go on it for a quick spin it all tightens up and that 1 inch slack has disappeared into thin air! so yeah just make sure you have enough slack in the chain m8
Leatherat Posted September 10, 2010 Author Posted September 10, 2010 Thanks for the replies, I just gave it some beans in neutral, and it's difficult to say if the noise is the same really. I'm going to go and slacken off the drive chain again, difficult job with only a side stand, and I'll let you know what happens. Would the drive chain being too tight cause the top end speed to be reduced?
Paulwhite Posted September 10, 2010 Posted September 10, 2010 not really but it will stretch and wear the sprockets down eventually, just undo the spindle so its loose (the big bolt that goes through the wheel) then adjust the chain tensioner (do 2 or 3 complete turns on each) then start the engine flick it in 1st and do a small "burnout" just 2 or 3 turns of the wheel then turn engine off check/adjust the chain then tighten everything up done! you dont want more than 1 inch of play in the chain. its tricky the 1st time you do it but once you know, it dont take 5 min.
Paulwhite Posted September 10, 2010 Posted September 10, 2010 if you get anymore problems or its still doing it then put a post up and il go through it to try and figure out whats up, (i know the engine inside out, iv had to strip and rebuild 2 of them lol) just do me a favor and make sure you keep an eye on the oil quality! seems to be the bottom end is a week point for the engine, and bad oil will make it go allot quicker!
Leatherat Posted September 10, 2010 Author Posted September 10, 2010 Thanks Chris & Paul, I have re-tensioned the drive chain, there's much more slack than I would have thought sensible, it's certainly looser than my GS550's but it has stopped or at least reduced to almost nothing the noise which is a good thing. As an aside, panniers are extremely handy but when coupled with the lack of a centre stand, they don't half make working on the back end a pain in the 'arris!
chris66 Posted September 10, 2010 Posted September 10, 2010 you will probably find you have a tight spot. when you adjust the chain it has to be at its tightest spot. push the bike forward a few inches and check chain tension every few inches to find the tightest spot adjust it so that you have an inch play then do it up,this may mean you have two or tree inches play at its loose spot. if this is so its a sign its time for a new chain and sprocket set. chris
Paulwhite Posted September 10, 2010 Posted September 10, 2010 ahhhh that would explain y it was a little tricky lol, and as iv said about 1 inch (4-5cm) of play from centre (either up or down) is about right for the engine size
Recommended Posts