spalado Posted June 5, 2013 Report Share Posted June 5, 2013 Pls help me analyze the reason of strange noise of engine. thk you Quote Link to comment Share on other sites More sharing options...
digger144 Posted June 5, 2013 Report Share Posted June 5, 2013 small end bearing,problem is con rod eye can be stretched so new bearing may not cure problem . that usually means complete rebuild of engine Quote Link to comment Share on other sites More sharing options...
dadof2 Posted June 5, 2013 Report Share Posted June 5, 2013 I would agree with small end or piston is likely problem but don't rule out a loose part in water pump or kickstart mechanism either. Cheers Quote Link to comment Share on other sites More sharing options...
taffe Posted June 5, 2013 Report Share Posted June 5, 2013 Hi, I had/have the same noise in my 07 Sherco 200. Replaced all top end [piston ok] and checked play as mentioned above. Rattle still there. Replaced crank bearings and seals, rattle still there. It's bean there for the last 12-14 months since the top end work. I read that it could the the two spacers on the piston pin that are used on the 200's, they are free to move between the conrod and the inside of the piston on the piston pin, apparently. I'm due to re ring the piston so I'm checking it all again. Bike goes like a train [for an old trials rider like me], in fact I detuned it in other areas to make more user friendly in the rocks. I'd be interesed in what comes of your question. Cheers Taff Quote Link to comment Share on other sites More sharing options...
copemech Posted June 6, 2013 Report Share Posted June 6, 2013 I may be missing something in the audio, but it sounds fairly normal to me! A fresh replate of the bore and a new piston should tone it down a bit, but time will take its toll on that as well. Quote Link to comment Share on other sites More sharing options...
tony27 Posted June 6, 2013 Report Share Posted June 6, 2013 You are missing something Cope, definitely more noise than there should be First thing I'd be doing is check every bolt you can get at for tightness especially the bash plate screws, head stay & engine mount bolts as any of these being loose can cause quite a bit of strange noise that can be mistaken for engine noise That will eliminate external noises at no cost before you need to start looking for issues that may not exist in the motor Quote Link to comment Share on other sites More sharing options...
copemech Posted June 7, 2013 Report Share Posted June 7, 2013 You are missing something Cope, definitely more noise than there should be First thing I'd be doing is check every bolt you can get at for tightness especially the bash plate screws, head stay & engine mount bolts as any of these being loose can cause quite a bit of strange noise that can be mistaken for engine noise That will eliminate external noises at no cost before you need to start looking for issues that may not exist in the motor Ring chatter, piston slap, primary gear rattle, clutch chatter and gear rattle all come into play, not to mention other vibrations due to loose stuff. I hear a lot of that in a lot of this, yet nothing particular standing out! Average rattlebox! Yes, yours is quieter after an overhaul! Quote Link to comment Share on other sites More sharing options...
charlie chitlins Posted June 9, 2013 Report Share Posted June 9, 2013 This exchange happened in my motorcycle shop...between my mechanic and a customer. "I have this little noise...but it's really hard to hear." "Well...come back when it's a big noise and it'll be easier!" Quote Link to comment Share on other sites More sharing options...
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