metalic rattle

[petejw]

my engine has developed a metalic rattle
sounds like a nut is bouncing around the engine,
it can be heard at idle, it quiet downs a bit under throttle
and returns when the revs are constant.
the rattle isnt coming from the cam chain or top end and
sounds like its on the left hand side of the engine somewhere,
ive got a stethoscope but cant pin point exactly where its coming
from, was wondering if any one else has experience something
similar or has any ideas what may have come loose, before i
start tearing down the engine.
thanx in advance.

[TopCatGr58]

Hey Pete,

I don't recall what engine work you have done on your bike, ie. dremel gear fix or such? I think I remember folks reporting that kind of noise when their countershaft bolt worked loose and was grinding against the inner side of the clutch bucket!? But I've also heard folks describe primary chain slap in a similar manner!? Good luck finding it, hope it isn't too serious, let us know what you find!

T.C.

[BA80]

That's what my original SG engine started doing. I tore the whole ignition out hoping it was something simple. No luck.

I still haven't torn into that engine but I assume it's a main bearing.

[BA80]

Hey Pete,

I think I remember folks reporting that kind of noise when their countershaft bolt worked loose and was grinding against the inner side of the clutch bucket!? T.C.

Other side of the engine TC.

[petejw]

hey TC,
ive done a top end rebuild a cpl of thousand miles ago
and have done the 2nd gear fix a cpl of years ago,
when i did the top end i removed the oil pan and found
a broken piece of bakerlite sitting in the bottom,
which came from the primary chain guide, up until now
there was no noise, so its quite possible that it is the chain
rattling, thanx for the reply.

[petejw]

hey greg,
doesnt sound like a bearing, sounds like its coming
more from the middle of the engine.

[BA80]

Hmmm... I thought you said left. Did you mean left center?



ahhhhh.......just read your previous post. Sounds like a slider fell apart. How's your chain tension?

[petejw]

im having trouble telling exactly where its coming from,
its not the top end, i can hear it more on the left side
than the right, the sounds travelling around the gear case/
timing covers, but could also be coming from the engine
under the carbs.

[BA80]

Drop the oil pan and see what's in there. More bakerlite and you'll know what's up.

Metal flakes and you'll HATE what's up.

[BA80]

Unfortunately this is what I found when I pulled my oil pan......

[crazy steve]

Unfortunately this is what I found when I pulled my oil pan......

That's never a good thing to find....

The only upside is they're still theoretically rebuildable... once you add 'extra' vent holes, they're toast...

[SFerinTEXAS]

May not be this but I heard a buzz/rattle on my SF a few weeks before the factory exhaust split under the heat shield. Drove me nuts till it became obvious.

[petejw]

greg, unfortunately ive been there before with a
rolled con rod bearing, never a pretty site.
ill drop the oil pan first and see what i find.

its definately a metalic rattle, like a nut rolling around
in a steel can, hasnt affected the way the engine runs,
tho i havent taken it out for a ride since ive heard the noise.

[rpgoerlich]

Developed a rattle at intermittent speeds last week. Found it Sunday. Turned out to be the front lower rivet in the RH exhaust, I believe to hold the baffle in place. Now to replace it...

[BA80]

That's never a good thing to find....

The only upside is they're still theoretically rebuildable... once you add 'extra' vent holes, they're toast...

As long as the bearing didn't take the case with it.

May not be this but I heard a buzz/rattle on my SF a few weeks before the factory exhaust split under the heat shield. Drove me nuts till it became obvious.

Developed a rattle at intermittent speeds last week. Found it Sunday. Turned out to be the front lower rivet in the RH exhaust, I believe to hold the baffle in place. Now to replace it...

Hopefully it's as simple as that Pete. Doesn't hurt to pull the pan though especially because you found what you did before.

The pan is an easy check.