Topic: Oh boy, a NEW sound! *SOLVED*

[DammitDan]

Here's one I don't think i've heard before...  It's a loud clicking, almost like a loose cam chain but not as violent sounding.

It seems to be coming from both sides, although the #1 side is quite a bit louder.  I recently adjusted the cam tensioner and readjusted valve clearances, and it didn't seem to be this loud before.   At first I thought it might be loose valves (cause that's what I think loose valves would sound like...), but I adjusted and re-adjusted the valves and it didn't go away.  The it's not a knocking, cause it doesn't really cause vibration that I can feel.  Just a loud "click" that follows the RPMs.  Doesn't get louder or softer whether I'm idling or running at speed, and it doesn't seem to affect performance.

The cam chain used to be pretty loud before I adjusted it... could it just have been masking this sound underneath when i fixed the tension?  Or is this something that I may have done when readjusting the valves or tensioning the chain?

If I can get my hands on a recorder I'll put it in MP3 form and send it in.  Any tips or suggestions would be helpful though!

Ah yes, on a 1982 CB650.

[cub]

I got that on my CB650 -81 and I thought as you that it was the valves. Adjusted and it sound a bit better. But after a few days it got worse again. I then checked the valves again and they were way so I had to re-adjust them. The sound then disappeared or at least got lower so I only hear the camchain rattle again. 

In your case, it could be the valves (again) but hard to tell without hearing it. 

[DammitDan]

I had a guy at the apartment complex suggest it may be my valve springs... Didn't even think to check those.

I has just assumed that it was a carb balancing issue (since I've never even touched the carbs...)  But I thought it a bit strange that it would happen all of a sudden like this, and only after I started messing with the valves.

[Geeto67]

check your exhaust bolts too. Sometimes the exhaust bolt can work itself loose and come off the stud, like my cb750F did recently. an exhaust tick will drive you crazy looking for other problems.

[dpen]

check your exhaust bolts too. Sometimes the exhaust bolt can work itself loose and come off the stud, like my cb750F did recently. an exhaust tick will drive you crazy looking for other problems.

Good idea.
Check mounting of everything around the front of the motor.
I had two examples of this.
1-loud clicking noise on FJ1200, seemed to move around the motor. Turned out to be vibration from a loose horn.
2-a not very nice vibration type noise from the engine of the BSA - a drumming set up by a cracked fuel tank mounting.

[DammitDan]

Well I did my first carb synch today... didn't fix the clicking noise, but at least my clutch rattle is gone and the thing purrs like a kitten.  Or clicks like a cricket.  Whatever.

So, what's my other options?  I'm 99.9% positive that it's coming from INSIDE the head/valves area and isn't just something rattling around (since it follows the RPM perfectly).  Exhaust headers are all secure, and I assume that I'm getting compression on all 4 since I could synch the carbs.  Would a weak spring somehow make a clicking noise?  Rocker arm?  Valve something or other?

Maybe I've got a small rodent living in my engine, trying desperately to tap out the answer to the meaning to life, the universe, and everything.  Maybe if I rev it up to 4200 RPMs...

[eldar]

Dan, I just tried to adjust the valves on my 78K. I drove my car today.
I have that tick that you describe I think and it comes from the valves being too gapped.

When I started, they were too tight and I did not have that moise but the motor seemed to fight itself a bit. I adjusted and now I have the tick but the engine seems to run a bit looser now and better.

So redo your valves and be picky about it. I will do that when I get home and I bet they will be better. I did not have quite enough time so I rushed and that was my mistake.

[DammitDan]

That was the ticket Eldar... I re-checked valve clearances today, and #1 was WAAAY too loose.  I didn't listen to the book the first time and assumed that TDC was the same on #1 and #4 (they're not...) and adjusted both #1 and #4 when only #4 was at TDC.  That left for some mighty big gappage on #1, when all the others were correctly done.  So, it was a loose rocker arm after all.

Now it really does purr like a kitten, with just the whirring of the cam chain.  And it's quiet... Almost, too quiet...

[eldar]

I hope to get that at least somewhat today, since I still need to do a carb sync.

[DammitDan]

I used Motion Pro's mercury manometer to do my sync.  Set me back about $50 but at least now I have the tool for the job.

Took me about 40 minutes total, after trying to figure out how to get to the #3 carb screw (it's lodged in between the metal throttle cable support on the 650).  Figured out that I could get to it by twisting the throttle, unscrewing the locknut, and then letting the throttle off and starting it up to play with the screw.