Topic: this much engine noise?? videos attached

[Elan]

Ok guys,

heres the background.
Just did an engine rebuild on my 750.
Bored to 826cc
new cam chain
everything rubber replaced
primary chains were within spec.
adjusted tappets
adjusted cam chain tension (still not completely confident about it)
and synched the carbs.
all air screws are exactly one turn out.

When it first starts up it sounds like junk at 1100rpm idle.

When it warms up, its sounds better but not quite as I would expect it.

heres a vid on cold start. i kept revving it up to about 1500 and thats where it seems to fade....

http://s1026.photobucket.com/albums/y321/elan_morales/?action=view&current=49c5019d.mp4

and here it is after just a few minutes of warming up...

http://s1026.photobucket.com/albums/y321/elan_morales/?action=view&current=7840b55b.mp4

Pulling in the clutch does very little.  otherwise it drives great.

[mrjack55]

Clutch!
Mine chatters too.  I hear tell that a good carb sync clears it up quite a bit.
Search the forum for "clutch chatter" or "noisy clutch".  There are a bunch of old threads about it.

[N30R3L0AD3D]

Going on what you said in your post...

That definitely does NOT sound good whatever it is... And if I were you, I'd split the cases and investigate.

[Danno]

sounds like at best you need to make it leaner at idle and sync the carbs but i think you don't have the timing chain adjusted right  sounds too loose

also could it be that you have too much clearance in a rod bearing ? they sometimes get better when they warm up
still almost sounds like the primary chain but you say you checked it and to make that kind of noise it would have been obvious

[Elan]

Not sure about the rod bearing...I don't remember it making this Boise before though, but I could have bought it with the engine warm.. And it was only firing on 2 cylinders anyway..

I just tool out the cam tensioner, and it is working properly. The only thing that's a little wierd is I'm putting it back in, so I fully compressed it, and it's already touching the internal tensioner before even sitting flush on the block... There's about 1/32" space. That space could easily disappear when I tighten it down, but still seems wierd.

[Elan]

No. Take that back, the tensioner wasn't pulling back all the way

[MCRider]

What method are you using to adjust the chain? Dynamic engine running, or static at 15° ATDC #1?

[Elan]

15deg past tdc 1-4 making sure #1 tappets are loose.
Just pit the tensioner back on and cam definately seems quiet, I'm fairly certain it's coming from the clutch now...
It pretty much vanishes at 1500rpm. And Is more subtle at 1100 rpm after warm.

It's just that pullin in the clutch doesnt seem to matter..

[MCRider]

15deg past tdc 1-4 making sure #1 tappets are loose.
Just pit the tensioner back on and cam definately seems quiet, I'm fairly certain it's coming from the clutch now...
It pretty much vanishes at 1500rpm. And Is more subtle at 1100 rpm after warm.

It's just that pullin in the clutch doesnt seem to matter..

Did you install new plates, or thoroughly clean the old ones? If not, reason being, they may be sticking and not responding to the "pull in the clutch" test.

I'd have to add, it didn't sound like it was in the best tune, carb synch etc. But the main noise is still more than expected.

[crazypj]

Does it quiet down above 3,000rpm?
Sounds to me like idle is too low and carbs are way out of sync.
 Get that sorted before tearing into it