nordy Posted October 2, 2014 Report Share Posted October 2, 2014 Hi All , need abit of help, 2011 sherco 290 started to knock for no reason replaced main , big end bearings con rod small end and pin, piston and barrel where perfect, but engine still knocking, puzzled, any ideas would be great. Thanks Quote Link to comment Share on other sites More sharing options...
thats_a_five Posted October 2, 2014 Report Share Posted October 2, 2014 Check the bolt on the flywheel. Quote Link to comment Share on other sites More sharing options...
nordy Posted October 2, 2014 Author Report Share Posted October 2, 2014 Thanks for the reply, checked flywheel nut, stator, clutch, every nut and bolt tight, even put the piston and barrel from a 2013 bike on , no joy still knockin, Its astrange one. Quote Link to comment Share on other sites More sharing options...
dadof2 Posted October 2, 2014 Report Share Posted October 2, 2014 Clutch rattle? does it change sound when clutch is pulled in. It is possible for a big end to knock and yet be very difficult to find any play in. Quote Link to comment Share on other sites More sharing options...
heffergm Posted October 2, 2014 Report Share Posted October 2, 2014 Is it only when you get off the throttle? If it's getting cooler where you are it may be time to richen up the fuel screw. Quote Link to comment Share on other sites More sharing options...
nordy Posted October 2, 2014 Author Report Share Posted October 2, 2014 Not clutch rattle, bigend bearing was replaced, could a new bearing be faulty?? Quote Link to comment Share on other sites More sharing options...
nordy Posted October 2, 2014 Author Report Share Posted October 2, 2014 The knocking is from start up and builds with the revs. Quote Link to comment Share on other sites More sharing options...
melba26 Posted October 2, 2014 Report Share Posted October 2, 2014 Have a look for damaged teeth on the kickstart idle gear and gear on clutch drum this engages with, this caused a knock a Gas Gas I had Quote Link to comment Share on other sites More sharing options...
nordy Posted October 2, 2014 Author Report Share Posted October 2, 2014 Had that on a gasgas aswell, was one of the first things i checked, thanks for that. Quote Link to comment Share on other sites More sharing options...
copemech Posted October 3, 2014 Report Share Posted October 3, 2014 Well, from what you have stated it is not the top end, the bottom end or the gears, so it must be fine! Let us see and hear a vid ofit! It is difficult to diagnose noises or the tinternet. My crystal ball sucks! You state replacing big end bearing? Possibly so, however last time I checked, thece come in a conrod kit with a new rod and crankpin. You know, the other mating wear parts there upon a true lower end knock. What is your clearance Clarence? There are only so many rotating parts there, you know! Quote Link to comment Share on other sites More sharing options...
naichuff Posted October 3, 2014 Report Share Posted October 3, 2014 Is the he crank running true after fitting big end Had one on a Villiers motor went out of true when tightening the sprocket and flywheel and twisted the shaft by a few thou Quote Link to comment Share on other sites More sharing options...
nordy Posted October 3, 2014 Author Report Share Posted October 3, 2014 Thanks Copemech, Naichuff,Melba26, Heffergm, Dadof2 and last but not least Thats a five for all of your input , Melba26 you where close , it turned out to be the clutch rubbers, never thought they would cause such a knocking noise, lesson learned, thanks again for your help. Quote Link to comment Share on other sites More sharing options...
tony27 Posted October 4, 2014 Report Share Posted October 4, 2014 Didn't consider the clutch rubbers & I replaced mine last year, it's amazing how much quieter the motor runs afterwards & is a cheap easy job to do Quote Link to comment Share on other sites More sharing options...
nordy Posted October 4, 2014 Author Report Share Posted October 4, 2014 I've heard a clutch with the rubbers gone before, this was a different noise altogether, thats why it took so long to find the problem, but atleast it sorted now. Quote Link to comment Share on other sites More sharing options...
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