knock in starter/trans/clutch area

[markb80]

I am hearing a mild knocking sound from the starter area. At first I thought it was piston slap, by the sound. I hear it some from the clutch side. It could also be coming from trans area. The sound only occurs when either
1) Idling in gear with clutch pulled in.
2) Idling in neutral with clutch in or out.

The bike starts great, runs great and shifts great, there are 22000 miles on it.
I'm not sure whether to go after the sound at the clutch side or the starter side.

Any ideas?

[Mike Hart]

Maybe it just needs a cam chain adjustment? That would be nice

[markb80]

I just did that. thanks for reply. I don't think the cam chain goes back that far, but I may be wrong.

[skids]

It could be caused by HyVo chain slap. This primary chain is not adjustible to my knowledge.

Another thing that can cause a knock sound is when the bike is running lean enough to cause rough idle. I have seen this with a colortune where the window shows a bright white flash in the combustion chamber. Maybe this could cause HyVo chain slap due to uneven loading on the crank?

[markb80]

I just loosened the two starter bolts that go through the plastic (I think it's plastic) cover and repositioned the starter slightly so that it was in the middle of the slop in the bolt holes, and the sound is definitely a few decibels lower. Now you must stick your head right near it to hear it.

It still bothers me a little, now it is just a rumbly sound though. I think there is something vibrating in starter (shaft?).

The bike runs very smooth at idle (and any other RPM), and I'm running premium gas.

Thanks for reply, maybe if I had louder pipes I wouldn't even have noticed it. I have stock ones in excellent shape, no leaks.

[markb80]

I just listened to my other XS11 (a special), I was keeping it elsewhere as I wanted lots of space to work on this one (a standard model).

The special runs great too, and has a 4-1 exhaust which is pretty loud. It turns out it the special makes exactly the same sound. I just never noticed because of the exhaust noise. The special only has about 14,000 miles. I just adjusted valves and cam chain on the special.

So I am beginning to think this sound is normal. The exhaust is just so quiet on the standard model (with stock exhaust) that you hear everything.

This reminds me of the old question,
"If a tree falls in the forest and no one is around to hear it, does it make a sound?"

If I just quit sticking my head down there, I think the sound will go away. If anyone else has a chance to listen for it let me know if you hear it too.