engine noises

Blueknyt · January 08, 2004, 10:01:41 PM

Ok, got the bottom end of my Gs straightened out now, but im still hearing a clacking on deceleration, in neutral, wick the throttle, you wont hear it when the R's jump up, but you will when they are coming down. idea? Valve clearences are well within specs. it runs good idles nice, pulls pretty good im kinda at a loss here most noisey once warmed up. Idea's?

Lars · January 09, 2004, 06:06:54 AM

Camchain? maybe the tensioner isn't working properly. Or something with the plastic guides for the camchain.

Briggs · January 09, 2004, 08:11:33 AM

I am just posting to say that I too have a wierd engine noise. Mine comes and goes when idling. It sort of clacks with the rpms. I am guessing its a cam chain or maybe piston slap. Dunno though. The bike itself runs great and pulls pretty stong. All I am trying to say is that I am in the same boat. I am going to look at it soon. Probably start by ripping of the head off and checking the valves and cam chain.
Mark

The Buddha · January 09, 2004, 08:56:31 AM

I'd say cam chain tensioner... but you have a manual one you made up right. So I dont know. But tensioner noises come up a few mins after starting. And when you turn the motor over with the valve cover off if the cam chain even for a second sags a little between the 2 cam sprokets... cam chain tensioner is bad.
Cool.
Srinath.

scratch · January 09, 2004, 08:59:41 AM

If it just clacks for aliitle bit and then goes away, while idling, like in a cyclic (on/off) fashion, that's just normal engine sounds, as long as it's not too loud.
It sounds like when the throttle is added, it removes any slack in the camchain, the camchain tensioner may be "near the tip of one of the teeth of the ratchet and prawl", just before it goes over that "tooth" and everything is back to normal...I'm just paraphrasing, that's why the "quotes".

Briggs · January 09, 2004, 09:42:50 AM

Actually it only starts and stops when idling and riding. Its. loud enough to hear when going say 30mph, and I have a V&H with no packing left. Ha...FYI I have 28,000 miles on it. Also I have a stock chain tensioner. I want to know waht goes bad in the tensioner? Do I just replace the tensioner or can I fix it? If it is bad, how do I know?

Blueknyt · January 09, 2004, 11:49:02 AM

i dont have the manual tensioner completed yet, still have the stock one, but while double checking the shims for correct clearances, i pulled the tensioner apart and wound the spring alittle tighter, chain seems tight.

The Buddha · January 09, 2004, 11:55:36 AM

Quote from: BriggsActually it only starts and stops when idling and riding. Its. loud enough to hear when going say 30mph, and I have a V&H with no packing left. Ha...FYI I have 28,000 miles on it. Also I have a stock chain tensioner. I want to know waht goes bad in the tensioner? Do I just replace the tensioner or can I fix it? If it is bad, how do I know?

Well mine ate the tensioner at 25K. So 28K is right in the ball park for that. Now I just pulled mine apart and rewound it (mine actually had a anchor come loose, so I put it back with a piece of wire as an additional anchor) and mercilissly flogged it for the next 18K and its not blinked once in that time. So rewind it. Its quite easy.
Cool.
Srinath.

TR · January 09, 2004, 05:37:08 PM

My bike does that kind of sound too, it has less than 10k miles and the Clymers says it's a rod pin or shoething like that, it might be an excesive gap, but can`t tell how dangerous it is to do nothing like I've done. Will check the Clymers later to tell for sure. I've always wanted it to be something else.

pattonme · January 09, 2004, 10:03:03 PM

a hyabusa aftermarket company makes manual adjusters for pretty much all bikes. No, I don't remember the URL.

Bob Broussard · January 09, 2004, 11:04:13 PM

The company is APE (American Performance Engineering)
You can check www.gsxrzone.com
Part #ST750GX

If you take the cam cover off, you can rotate the motor to a point where no valves are being opened. This spot puts the least tension on the cams and chain. This is where I locate the cams to tighten the cam chain.
If you pop the stock chain tensioner in and it doesn't seem to tighten enough.
You can manually screw it in a little more.
Also check and make sure you put the plastic guide in the front of the chain when you re-assembled the motor. I left it out once

sprint_9 · January 10, 2004, 12:04:01 AM

Mine also has the same sort of problem, though it cant be heard at 30 mph. It can be heard at idle, but when revved up it will go away but come back again when the revs come back down, also it seems to only do it when it is really hot outside and the bike is real good and warm. Im guessing valves? Any others?

Blueknyt · January 10, 2004, 12:31:31 AM

well, i cant say i know what piston slap is, i would figure you would hear that when its cold, piston expands with heat tightening up the fit. not to mention for a piston to be worn for enough clearence to slap the cylwall, would think the rings would be as pour shape and have LOTS of blowby/oil consumption. wrist pin? dont know, never heard one before. when the engine is cold, you dont hear it, or jsut a clack or two on deceleration. use to hear a clack once or twice while idleing. wondering if the guides are going or binding and the clack is the valve slaping home. im gonna have to make a damn adapter for compressing the valve springs.

Briggs · January 10, 2004, 01:11:34 PM

Bob, are saying that the part you pointed out will work for the GS?

Briggs · January 10, 2004, 07:52:40 PM

Here is the update...

I have removed my cam chain tensioner...Guess what I can't push the plunger in. NOT EVEN A LITTLE! I If I take a screw driver and turn the spring clockwise I can get it to go in. Then if I release it, the plunger will fully extend. This is good, but it will not go back in unless I use a screw driver on the spring.

In my opinion this would mean a defective tensioner. I would be curious if anyone out there knows if this is true. Someone plaese confirm this!

Also, I still interested to learn more about the one that Bob pointed out.
If it fits, it sounds like a great alternative to the stock piece.

Mark

Blueknyt · January 10, 2004, 10:19:48 PM

tensioner is working properly

KevinC · January 11, 2004, 09:40:42 AM

Briggs, that is how the tensioner is supposed to work. It ratchets out as far as possible, to take out all the chain slack, and continues to move out as things eventually wear. It's not supposed to be able to go back in without turning the screw.

And that manual chain tensioner Bob spec'd will fit the GS.

Briggs · January 11, 2004, 12:09:37 PM

Ok, sounds good then. Thanks for all the help people. I think I am going to try that manual one anyway.

Also I finally got to take a looka t the valve clearance. To my surprize I have ZERO.

Could this be part of noise problem? hmmm....Going to get new spacers on monday. We will see what happends.

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