cam chain adjstmnt then white smoke!

[oldyam80sg]

The only thing i could think of is the cam chain adjustment you did loosened up.

[Ivan]

The only thing i could think of is the cam chain adjustment you did loosened up.

That does tend to happen. Especially if you do a lot of high rpm stuff. It's a happy balance between stripping the tensioner threads and keeping it from backing out.

[tenonry]

Should I try to readjust the cam chain and see if I still hear a wicked rattle?

[Ivan]

I think that would be my first step.

Just be careful not to strip the threads in the tensioner. Also, when you snug the bolt down, don't over tighten the nut. I have found that it can pull the lock bolt back out, ever so slightly. I think the spec is 10 in-lbs, which is less than one ft-lb.

[oldyam80sg]

It wouldn't hurt but if it does shut it down.See if it did come loose.

[wa407mpp]

My first step would be to pull the cam cover and have a good look around, if it is a loose chain just making noise, with no damage yet, and then you start it again, without knowing what is wrong, you might do some real damage.

[DGXSER]

I would suggest pulling the valve cover and looking in there. Check the torque on the cam retainer bolts. Also check your valve clearances, if one is bent you will find it in the clearances typically.

If you do not find any issues with the clearances, or cam retainer bolts/nuts. I would then proceed to cam chain tensioner adjustment.

[Larrym]

If the tensioner cam loose then it didn't just back out while the bike was sitting there, It would have backed out while the engine was running.

If the engine was running then the "centripetal" force would have tended to keep the cam chain "out" and therefore tight enough to prevent it from jumping a tooth?

If the engine was shut off then the additional slack in the cam chain might have dropped to the bottom near the crank and allowed the jumping of a tooth.??

Before starting the engine I would suggest trying to turn it over by hand: via the same method you used to adjust the tensioner in the first place.

Notchiness or any "hard stops" is an indication of a slipped tooth and risks bending valves.

[Silent]

Re-adjust your cam chain tensioner. It may have slipped and the racket you're hearing may just be a loose cam chain.

[Ivan]

It has been my experience that the cam chain will make A LOT (A LOT! REALLY!) of noise before it gets to the point of jumping teeth.

Also: typically the "something loose in the top of the engine" noises seem to be noisier when cold. My XS rattles around like crazy on a cold start up, and calms down when warmed up. I don't know why, maybe the valves are set a bit loose, or the cam chain is on the loose side, but it runs strong, and I am happy.

The ultra safe thing would be to pull the cover and check that all is in time. I suspect you will find it is.

IIRC there was a member that had one of the cam cap nuts come loose and cause a lot of noise without doing any damage, and it may serve you well just taking a look around for something obvious like that.

Still, if it were my scoot, I would adjust the cam tensioner and see what that does.