mosh Posted February 28, 2014 Report Share Posted February 28, 2014 hello and thanks for any help in advance. hello ive got a knocking noise when im in gear and riding and soon as i let off it stops, also when im in low revs there is no noise and im not sure if its normal because ive only just got it and its an 08 model. if you need any more info just let me no and i hope ive explained good enough Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted February 28, 2014 Report Share Posted February 28, 2014 youre lucky it runs. 1 Quote Link to comment Share on other sites More sharing options...
gasgas249uk Posted February 28, 2014 Report Share Posted February 28, 2014 From what you describe , it sounds as though your big end bearing is shot . If this diagnosis is correct then the engine will need to come out and be completely rebuilt. Before you do anything , get an experienced mechanic to look over it Good luck. Quote Link to comment Share on other sites More sharing options...
mosh Posted March 1, 2014 Author Report Share Posted March 1, 2014 cheers fella ill go take it some where next week and see if they can diagnose it properly and i hope its not the big end bearing as i just cant be bothered to strip the thing down Quote Link to comment Share on other sites More sharing options...
mosh Posted March 5, 2014 Author Report Share Posted March 5, 2014 well had the day off today and had a good look at the bike turned out that it was the front sprocket, it was worn as hell and that bad it had started bending so that what was causing the knocking noise the chain hitting the bent teeth soon as i put a new one on it was like a good en 1 Quote Link to comment Share on other sites More sharing options...
elliotsdaddy Posted March 5, 2014 Report Share Posted March 5, 2014 Ooooo you've got to love a cheap fix. Nice one fella. So using 'Man Logic', technically, since no rebuild was required, you are a fair few hundred quid up......what you gonna buy? 1 Quote Link to comment Share on other sites More sharing options...
mosh Posted March 5, 2014 Author Report Share Posted March 5, 2014 yeah all sorted for a tenner so yeah i think i might either get some protection for the bike to stop me smashing it up as quick on the rocks or some nice anodised stuff to smash up on the rocks, decisions decisions 2 Quote Link to comment Share on other sites More sharing options...
tltel Posted March 6, 2014 Report Share Posted March 6, 2014 If your sprocket was that badly worn, the chain is probably shot too, which means your rear sprocket probably needs changing too. voice of experience! If your chain snaps on a big climb like mine did when I first got my gas gas,. you wouldn't believe how fast you can go in reverse with no chain attached. TLTEL Quote Link to comment Share on other sites More sharing options...
cactusjack Posted March 6, 2014 Report Share Posted March 6, 2014 If your sprocket was that badly worn, the chain is probably shot too, which means your rear sprocket probably needs changing too. voice of experience! If your chain snaps on a big climb like mine did when I first got my gas gas,. you wouldn't believe how fast you can go in reverse with no chain attached. TLTEL Agreed. The other issue is the chain at revs may fly forward and put a hole in your engine case, which is generally unrepairable. A very expensive repair will ensue. Do the chain and rear sprocket too mate. Quote Link to comment Share on other sites More sharing options...
mosh Posted March 7, 2014 Author Report Share Posted March 7, 2014 its a brand new rear sprocket and chain so i can't understand why the feller who i got it off never put a new front sprocket on Quote Link to comment Share on other sites More sharing options...
lineaway Posted March 7, 2014 Report Share Posted March 7, 2014 How long have you had the bike and how many hours have you put on it? It sounds like the Bloke you bought it from was being a tight ass and only bought parts you can see. Just because the front is totally worn out does not mean the rest is junk. You can check the chain wear on the rear sprocket. You can visually see how much wear is on the rear sprocket. Trials bikes are run slow. The chain Gods are not going to frown on you if you just replace the c/s sprocket. This logic of sprocket wear should translate to every time you replace the main bearings you rebuild the rod. Ha! Quote Link to comment Share on other sites More sharing options...
copemech Posted March 7, 2014 Report Share Posted March 7, 2014 What is the frequency? That may sound like a stupid question, however, as in this case the knock would be totally unrelated to engine speed(rpm), yet more related to vehicle speed and load. Think about that then one is better able to sort things out! And yes, that little front one is going about four times faster than the rear! Motor much faster than that! Quote Link to comment Share on other sites More sharing options...
shercoholic Posted March 9, 2014 Report Share Posted March 9, 2014 Best to keep an eye on the chain and sprockets in the future, as with the standard 9t c/s the chain plates are working hard, and the torque of the 320 is tough on those six little splines ...but then who doesn't love torque! (maybe not ND) Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.