My 2000 vtr1000 has developed a new noise all of a sudden. I have a feeling it is coming from the cam chain/guide/cct. It sounds like a rattle/knock. Bike has 20,000km (12,500mi) on it and before this I considered the engine to be pretty quiet mechanically...so this new noise is VERY noticeable.

This is what I was doing immediately before the noise started...

I had my clutch off to install the factory pro shiftstar kit. This was straightforward, but when I put it back together and started it, this new noise was immediately there. The engine seems to run fine, other than there is a hesitation when I crack the throttle from idle. This was not there before either, but probably attributable to some jetting experimentation that I am doing. I did the latest round of carburetion changes while I had it apart for the shift kit install and I finally did the TPS fix too at the same time . Other than that hesitation it seems to run fine - except for the new mechanical noise of course. Having said that, I admit I did not take it out and ride it as I was worried about doing some damage because of the new rattle.

Does this sound like it is likely cam chain and guide/tensioning system?

The only out-of-the-ordinary thing that happened when I had it apart before the noise manifested itself... is that when I was installing the big nut on the clutch basket, I tried to hold the rear brake on myself (in gear) to keep the engine from turning while I torqued the nut. I slipped the engine turned at least some while I was trying to torque that nut.

The clutch seems fine. The noise doesn't change whether the clutch is engaged or disengaged. I have it apart again, and there is no sign, at least with the clutch cover off - that there is anything wrong. I ran a magnet around in the oil sump and got no sign of any ferrous debris.

I am waiting for APE CCTs, which I will install before it runs again, and I will follow proper procedure as respects timing (and check valve clearance) when they arrive. I did pull the CCT from the front cylinder. It came off without incident, but I note that the plunger won’t retract by pushing on it. It will retract by turning the slot on the plunger shaft inside the body of the tensioner.

Any thoughts/guidance would be most appreciated.

 

Well if it was fine before you took it apart and started making noise on reassembly, I doubt it's the CCTs. You need to go back and check all of your work until you find the cause of the problem as it is most likely something that you did.

 

Also did you make sure the cams were not putting pressure on the valves when you removed the front CCT? If not, you may have caused the chain to skip teeth.

 

By the way I read it the CCTs have not been changed yet.

 

But he did pull the front one (last paragraph) and all you need to do to jump teeth is pull a cct when the engine is not in the correct part of the stroke.

 

Missed that....damn and if you let it extend all the way when you pulled it out, instead of winding it in and locking it, that could be the problem..... got to work on my reading........ but it was early here on the left coast....

 

It is really hard to prescribe over the net, but from what you describe I would suggest that you have not got the details right on the CCT reinstall. The CCT is a threaded shaft that is spring loaded so that it can vary the pressure on the guide and chain. Did you make sure that the spring was still doing it's job? The spring is the bit that breaks and the CCT backs off, then the chain gets loose, then it jumps teeth and you have a minor disaster of valves hitting pistons and bending.
These motors are nice and simple (compared to IL4's and desmo's) but it is vital that you get the details right and follow the manual to achieve best performance. e.g. placement and orientation of washers.
Ditto to what was said above, the issue probably lies in something that you have worked on, rather than a something new.

 

If you pulled the CCT to check AFTER the noise started then chances are it is something else. It may be just a coincidence that the CCT let go of course. Check the cam tmimng as suggested. Never pull a CCT out without knowing what you are doing.

When you do a job and a noise appears immediately afterwards, then it is a good chance you have got something wrong. Don't discount the water pump assembly. That needs to be lined up properly when putting the case back on.

 

Maybe it's the new parts that are rattling, +1 on the water pump shaft.
The gasket should still be ok if you re open it soon, it take time to stick to the case.

 

the cams were in proper position when i pulled the front cct, but again, that was after the noise started. the front one is functioning fine. this weekend i am going to put the front one back, then take out the back one and check that. The APEs arrive mid next week, but i will verify function of rear cct as well as valve timing before then.

While i am not an expert, and i am just getting to know the vtr, i have been working on my own bikes for 40 years. I have had ( and do have) many, so i am not a beginner either. I will report back on findings. thanks everyone for the very quick feedback.