Weird Rattling

[satchmo]

Hey guys. Just needing some technical help.

On my 77 gs550 I get this weird rattling around the 5000 rpm mark both on acceleration and decelartion. It only happens around this rpm setting. I can't really describe the sound, but something akin to ball bearings in a tin can. But not quite as distinctive.

Any suggestions?

Satch

[Anonymous]

Re: Weird Rattling

Hey guys. Just needing some technical help.

On my 77 gs550 I get this weird rattling around the 5000 rpm mark both on acceleration and decelartion. It only happens around this rpm setting. I can't really describe the sound, but something akin to ball bearings in a tin can. But not quite as distinctive.

Any suggestions?

Satch

check your timing chain adjuster

[satchmo]

How the heck do I do that?

Is it something I can do?


Satch

[Anonymous]

How the heck do I do that?

Is it something I can do?


Satch

I have a manual chain tensioner--the proceedure is in the repair manual--or ask someone to get it for you--i dont know it

[earlfor]

This was posted by Billy Ricks some time back and I'm pasting it here.
He says it all. :-)

CAM CHAIN TENSIONER

First, never turn the round knob on the cam chain tensioner unless you
plan to remove it and go through the entire procedure that follows. Now
as for how to check its operation.

With the tensioner removed from the cylinder block loosen the lock nut
on the left side of the tensioner and back the slotted bolt out ? turn.
Turn the knob on the right side of the tensioner, which in the Suzuki
service manual is called a lock shaft handle, counterclock-wise. As you
are turning the knob counterclock-wise push the pushrod all the way
back. Keep turning the knob until it refuses to turn any further.

With the pushrod still pushed in as far as it will go tighten the
slotted bolt so that the pushrod will not plunge out.

Remount the tensioner to the cylinder block. If the tensioner is not
going in turn the crankshaft clockwise slowly to get slack in the cam
chain on the intake side of the block.

Loosen the slotted bolt ? turn allowing the pushrod to advance towards
the cam chain. Tighten the lock nut but leave the slotted bolt loose by
that ? turn.

While turning the knob counterclock-wise, slowly rotate the crankshaft
in reverse direction, counterclock-wise. This causes the chain to push
the pushrod back.

Release the knob and slowly turn the crankshaft in the normal direction,
clockwise. You should see the knob rotate as the chain becomes
progressively slackened. If it does the pushrod is obviously moving
forward under spring pressure signifying the tensioner is in good
operable condition. If it moves sluggishly or not at all that means the
pushrod or the slotted bolt is sticking. If so remove the tensioner
from the block again and inspect the pushrod. It could need cleaning or
could be bent or galled. Further crank rotation will take the slack out
of the cam chain.

After the tensioner has been properly set up never attempt to turn that
knob again in either direction unless you intend to remove it and go
through the above procedure

Earl

How the heck do I do that?

Is it something I can do?


Satch

[Don Lobacz]

I would guess that it is in your exhaust. A camchain problem will only get worse as the revs climb. Bang on your exhaust with a rubber hammer and see if that's not it.

[Anonymous]

I would guess that it is in your exhaust. A camchain problem will only get worse as the revs climb. Bang on your exhaust with a rubber hammer and see if that's not it.

Yes, it could be a resonance problem. I would put the bike on its center stand (in neutral, of course) and rev it through the problem range. You might be able to locate the souce of the rattle very quickly. I have heard that using a screwdriver as a "stethoscope" can narrow down the location of the noise source, if internal to the engine. Put the metal blade on various parts of the engine with the handle to your ear and see if you can narrow down the problem area.

[argonsagas]

I would guess that it is in your exhaust. A camchain problem will only get worse as the revs climb. Bang on your exhaust with a rubber hammer and see if that's not it.

Yes, it could be a resonance problem. I would put the bike on its center stand (in neutral, of course) and rev it through the problem range. You might be able to locate the souce of the rattle very quickly. I have heard that using a screwdriver as a "stethoscope" can narrow down the location of the noise source, if internal to the engine. Put the metal blade on various parts of the engine with the handle to your ear and see if you can narrow down the problem area.

In absence of a mechanic's stethoscope, the screwdriver will work, but unless it was a very long one, I would not use it near the exhaust....too much heat and too much chance of burning yourself if it slips at all. I have used wooden broomsticks in the past on car engines and machinery...they work well and don't conduct heat.

On the bike you might want something shorter....

[Anonymous]

I have used wooden broomsticks in the past on car engines and machinery...

Given your character, Ron, why do you need a car if you have a broomstick?

Sorry. I should I have confined this jibe to the General Discussion section.

[satchmo]

thanks for all the help, I really appreciate all the info.

Satch

[Anonymous]

Lies all lies Satch

[Anonymous]

weird rattling

If you have a fairing on your bike, the fairing will tend to act like a parabolic dish amplifying and focusing sound from almost anywhere on the bike to make it sound like it is coming from the gastank/engine area. On my bike, the rubber ring that holds the mirror into the mirror bezel had come loose allowing the mirror glass to rattle in the bezel. The racket sounded like it was coming from the steering head area and only appeared at certain rpm's. If you have determined that the rattle is not coming from the engine, try holding your hand over different chassis parts to see if it stops the rattle. Good luck.

Junkman

[moto_dan]

Re: Weird Rattling

Hey guys. Just needing some technical help.

On my 77 gs550 I get this weird rattling around the 5000 rpm mark both on acceleration and decelartion. It only happens around this rpm setting. I can't really describe the sound, but something akin to ball bearings in a tin can. But not quite as distinctive.

Any suggestions?

Satch

My brake stay arm made a similiar noise as you described at certain rpms. Tightened it up, noise gone.