Unsettling rattle

[DuncanS]

I'm noticing more and more a clunking rattle when accelerating from low revs. It's like a deep click sound and it also makes enough of a vibration for me to feel it on the foot pegs, especially the left. Generally I get it only three or four times before revs are up and it goes away.

Doesn't happen at all in neutral or with the clutch engaged so it's difficult to get an idea of exeactly where it's coming from because I have to be actually riding it to produce it.

Any ideas? It could almost be chain rattle around the front sprocket, chain is close to end of life but is properly adjusted and well lubed. Other than that... Gear box? Sprocket? The bike is an 03 750 with 45000 miles on it.

Cheers
Duncan

[joseph2027]

try puting on the stand then put it in gear and see if you can pinpount where. but D@#$ YOU BEEN rideing that thing mines a 04 with 6087. on it

[hardlydangerous]

Do this
find an open stretch of road
get it up to 30~50 mph in second gear shift it to neutral and shut the engine off and let it coast.
As the bike slows listen and feel for the vibration/noise. My quess is you have a bad link in your chain causing it to bind up or a badly worn front sprocket. It could also be a bad wheel bearing.
If there is no vibration with the engine off and rolling then its the engine.

[Maxxrox]

Hm. Your bike re-jetted? Stock filters and exhaust headers?

May be running a smidgen rich?


--B

[Kfreak]

While you are checking the chain, pull the rear wheel and check your cush drive in the rear hub. I have a slight knock in mine. I can see some play in the hub with the bike on the center stand while moving the wheel.

[kevin2502000]

I had my horn touching my valve cover and it would rattle clunk with the rpm till I tightened it up.

[The CyberPoet]

I'm bettin' it's the chain.

Cheers,
=-= The CyberPoet

__________________________________________________ ________
CyberPoet's Katana Maintence and Upgrade Parts Offerings
The Best Metal Steel Aluminum Motorcycle Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.

[IndyGunner]

chain

[KansasKat]

My 05 Kat 750 (50k miles) is doing the same thing.
If it were the chain wouldn't it make the sound regardless of whether it was in gear or not?

[IndyGunner]

cam chain?

[The CyberPoet]

My 05 Kat 750 (50k miles) is doing the same thing.
If it were the chain wouldn't it make the sound regardless of whether it was in gear or not?

Not necessarily -- the chain may have to be under tension to make the noise. A clicking is usually a stuck link suddenly giving way and snapping the roller down to the low spot between two teeth on the sprocket (and it won't do it without tension from the engine), or the chain itself slapping the swing arm.

Cheers,
=-= The CyberPoet

__________________________________________________ ________
CyberPoet's Katana Maintence and Upgrade Parts Offerings
The Best Metal Steel Aluminum Motorcycle Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.

[scottynoface]

or the chain itself slapping the swing arm.

Yep, that one's fun. (see my garage pic, that chain was nasty)

Manifests as a nasty clunking sound from 0 to ~20mph. I thought for a while it was from the front of the bike, but when I looked forward and down the noise came into the back of my helmet.

[arsenic]

[KansasKat]

Not necessarily -- the chain may have to be under tension to make the noise. A clicking is usually a stuck link suddenly giving way and snapping the roller down to the low spot between two teeth on the sprocket (and it won't do it without tension from the engine), or the chain itself slapping the swing arm.

That makes sense....thanks Cyber!!!

"Manifests as a nasty clunking sound from 0 to ~20mph. I thought for a while it was from the front of the bike, but when I looked forward and down the noise came into the back of my helmet."

-Thats exactly what mine is doing.

[The CyberPoet]

You might be able to temporarily rescue the chain by putting the bike on the centerstand, laying a towel/rag under the full length of the chain, starting the bike & putting it in gear, and then spraying excessively with WD-40 or a thin moly-based lube to carry away anything that's binding the chain.

On the other hand, it won't resolve the damages that this link repeatedly snapping down the roller against the sprocket teeth did, and I would recommend budgeting for and ordering a replacement chain & sprocket kit, replacing both sprockets and the chain. In the future, clean & especially lube your chain more frequently, using an oil-based lube instead of a wax-based lube. Generally, spraying a 6" length of chain (or just the chain where it passes over the rear sprocket) with an oil-based lube every single time you take on fuel should be sufficient to get you 24 - 27k miles out of a set of chain & sprockets on the Kat.

Cheers,
=-= The CyberPoet

__________________________________________________ ________
CyberPoet's Katana Maintence and Upgrade Parts Offerings
The Best Metal Steel Aluminum Motorcycle Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.