Yamaha TRX850 Enthusiasts Forum

Can anyone out there help me ? My bike Australian 2001 delivered with 20,000klms has sudenly developed a strange pinging noise, but only in 4th gear at 4-4500 revs and only under load.It does not make this noise in any other gear regardless of speed/revs/load.My bike is modified with vee2 cams, dynojetted standard carbs,k&n airfilter,staintune cans and a belly pan.I removed the belly pan and the noise was still there.The bike was recently serviced but the valves have not been checked for some time.I know this is a obscure question, but maybe someone out there has had a similiar thing happen to them and their help could save me valuable riding time.I have been right over the whole bike and checked all nuts/bolts,but to no avail.

G'day Ken. Never had this problem myself but i don't believe its a common one with the TRX. How long has it been happening? Could it be down to bad fuel? That's probably the first thing I'd check. Otherwise, at 20,000 klicks it is hard to believe the heads would be severely coked up, but its possible. No doubt the more mechanically minded here will dive in with other suggestions, such as whether the Vee2 cams are known to promote this behaviour. cheers

Ken hi the gear in the box may be damaged in some way. eg case hardening worn through or something like that. May pay you to drop the oil and filter out and look for metal. If you find heaps of metal take the sump off and check there too. Depending on what you find or if the noise gets worse you may have to delve inside the box. However someone here may be able to put your mind at ease. Good luck with it.

i had this on my firestorm it turned out to be the cam chain tensioner ,you going to get 20 different answers,,, can you take it to a bike mechanic and let him have a listen ??