2006 sxr800 grenade noises

[mybad]

Please help. I bought a new sxr800 and immediately sent the motor to group k for their big bore kit. Basically 834 c.c.s and modifications to the stock head, porting, exhaust plumbing, intake manifold and carbs. Everyting else is stock. Ive run the boat on the water gently for 1 hour. It sounds like a grenade at low rpms. Lots of pinging and chattering. Seems to lessen as the rpms rise. Makes the noises regardless of engine temp.(hot and cold). Runs strong on the water. Have not completely broke the ski in yet so no full throttle pulls. Less than 1 hour on this new ski/motor. Ive already tore the motor apart to visually check everything and it is clean. No scoring or markings anywhere. Do all sxrs make this chattering and pinging noises? Any common areas to inspect that could be causing this? Thanks in advance.

 

[FLY6584]

Please help. I bought a new sxr800 and immediately sent the motor to group k for their big bore kit. Basically 834 c.c.s and modifications to the stock head, porting, exhaust plumbing, intake manifold and carbs. Everyting else is stock. Ive run the boat on the water gently for 1 hour. It sounds like a grenade at low rpms. Lots of pinging and chattering. Seems to lessen as the rpms rise. Makes the noises regardless of engine temp.(hot and cold). Runs strong on the water. Have not completely broke the ski in yet so no full throttle pulls. Less than 1 hour on this new ski/motor. Ive already tore the motor apart to visually check everything and it is clean. No scoring or markings anywhere. Do all sxrs make this chattering and pinging noises? Any common areas to inspect that could be causing this? Thanks in advance.

I've heard that SXR's have very noisy/vibrating pumps. Are you feeling this chattering in the tray?

The first time I test rode an SXR I brought it back to the salesman at the dock and told him something was wrong with it cuz of the vibrations I was feeling and he said that is normal on the SXR's.

Yours sounds like it may be a little worse than that though.

 

[mybad]

Yeah the pump is noisy but normal. I just expected the motor to sound smoother. I thought that by having all my modifications done by one of the best engine builders around that I would have a solid motor. Im hoping its the nature of the modifications and not something else. The guys at group K are very talented people and have answer all my questions. Im just checking with other sxr riders to see if they have experienced this similar noise.

 

[vomitspot]

did you reinstall the coupler rubber?

 

[94SJrider]

My uncle has a sxr with a factory pipe dry i believe and it makes a lot of loud annoying pinging and chattering sounds, vibrates like crazy too. powerfull ski though. so my guess is that its normal but im no expert

 

[mybad]

Yes, the coupler rubber was reinstalled. I will double check the coupler placement and hose clamps for tightness. I still have the stock exhaust with modified plumbing and internals.

Thanks

 

[Superjetjim]

Probably the increased compression - makes them all (SJ & SXR) bounce around on the mounts - a dry pipe fixed to the head makes it even worse..

 

[mybad]

Anyone using aftermarket mounts? What should the bed plate and motor mount bolts be torqued to?


I torqued the headpipe to the manifold with 22 ft. lbs. What is a safe number? Im thinking maybe 32ft. lbs.