Weird Noise, CCT or Slide Chatter?
 

Hi SH forums,
For a while now my chicken has been making a rattling sound at low RPMs (less than 3k) while taking off, crusing, decelerating, and sometimes while idling. It only occurs after the engine has warmed up.

I heard that this bike can have significant carb slide chatter, but I am not familiar with how that sounds. I want to replace the CCTs, but I don't want to drop the cash if they're not broken.

Here is a video with the sound. It is prominent as the revs are falling.
Do I need to be worried about this sound?

Thanks,
Nathan

If I were in your shoes, I'd do cct's and check valve clearances at the same time, and I wouldn't ride it till complete. To me, that doesn't sound like carbies.
Do you know the last time valves were checked, what's the mileage now?

change your ccts before they drop you in a whole world of shit....

I checked the CCTs and did the valves today. The springs in both the ccts still held tension. They were pretty hard to unwind.

Rattle is still there however. Local mechanic says only thing he can think of at this point is rod knock. Any thoughts?

The tension of the CCT springs is not an indicator of anything more than it's a spring. The springs just fail, without warning of any type.

Thing is the springs havent failed yet but my bike is still making the noise.

Have you checked for exhaust gas leaks from the manifold / header connector as a gasket failure in that dept. can lead to a pulse 'rattling' noise.

Send a used oil sample to Blackstone Labs for analysis. The report will give you a pretty good indicator of the internal health of the engine. This will rule out a lot of expensive dead ends.
Oh, and it is perfectly clear that your CCTs have not failed, yet.

Was about to say, kinda hard to determine by video sound, but seems like you can hear exhaust leak...

That sounds like a pretty good thing to do. When I did the valves I may have let a little dirt into the heads (windy day). Do you think that may affect the results?

And yep I keep hearing mixed reviews about the auto CCTs. Most people I talk to in person say keep the auto ones, but the forums seem pretty dead set on the manual ones. I think for now I'll do the stopper mod.

Lastly, I have access to my brother's VTR (he got one because he liked mine). Will check to see if that one has the same kind of rattle. His has Jardine pipes though, so it might be tougher to hear.

Does the sound change if you pull in the clutch while it's idling?

I havent checked that actually, but it does occur in gear while riding so I'm doubting its the clutch. Will be back with my bike in a few days so I'll check it then.

Well I tried my brother's VTR today, and his definitely does not make the sound. Im starting to think it might be a rod knock. Could that possibly be the sound?

Paging J.I.

Use a large screwdriver, place the blade all over the engine while running and place your ear against the handle of the screwdriver. You'll hear a lot of scary noises, but one will stand out. This will help you pinpoint the problem, especially since you have access to another bike to compare it to.

I tried the screwdriver trick and I didn't like it so much, so I got an actual stethoscope. Each time I try to diagnose the sound, it isn't present unfortunately. I think when the oil gets too warm it stops making the sound, which is kind of strange.

So far I've heard clattering from the rear CCT, but I need to refine my methods before I draw any solid conclusions. Will keep trying over the next few days.

That is a bit strange, from my V-twin experience the front is usually the one that gets punished, unless the carb is way lean. You may be onto something that will make many of us scratch our heads. Try rolling the throttle slowly and identify at what rpm the noise is present. If the chain is under tension at all time, it normally won't make noise, and if its not an exhaust leak, than it probably is a valve issue, hopefully not. How is the temp on both cylinders? Compare the two to see if there is a difference, which is either caused by friction or lean fuel mixture.

Had more time to check the noise today. Here, s what i found.

-Noise occurs when engine is partially warmed up
-Stronger from the rear cylinder
-Clanking heard with stethoscope over rear cam chain area.
-Front cam chain has much less noticeable noise

I am going to replace the rear cam chain tensioner. If the noise goes away, I'll replace the front as well to be safe.

Just a suggestion: Pull the valve covers before any thing else. This will give you a crystal clear view of what is going on with the cam chain. Also, at the absolute minimum, replace the auto CCTs with new ones. Or, as this would be a good opportunity to do the stopper mod, if you're not going to do manual CCTs.
$.02

See post 2, 3, 4...

Or wait till something breaks, then you know what to fix. :eek:

Going to change the oil today. If it comes out ok (not glittery), I'll finally cave in to manual ccts.

APE ccts seem hard to come by. Where would be a good place to pick up a set? Could i go with off brand ones instead? On ebay they seem to be about half the price.

Krieger cam chain tensioners

I had a set of Kiegers and a set of off brand Ebay specials. With the exception of the quality of the anodizing and lack of gaskets, I couldn't find a quality or dimensional difference. I installed the off brand ones in my SH 20+k miles ago with no problem, so far. I did however use the VTR1000.org write up on adjusting them.

Krieger Cam Chain Tensioners

VTR1000 S'hawk/F'storm

Oil came out with only little microscopic particles of metal, but not enough to convince me that ive spun a bearing.

Ordered mccts, will be going in next week. Will update on how they turn out.

any news ?? I encounter the same kind of noise !

Hi nrowah,
please tell us any new details about your repair. I ran into a similar problem and still have not found a solution.
Greetings from germany

CHANGE THE CCTs...... this shit about them being ok is total balls, dont believe people, every dead vtr in the world died because of??? ccts....they give little of no warning, the first thing you will know about them is the front pot shitting itself all over the road