Bad vibration/Noise when pulling out?

[97GSX600F]

I searched and searched but could not find a similar problem like mine. When pulling out 5-10 mph and give it 3/8 to 1/2 throttle and more, my 97 has a hard vibration all over. Sounds like the noise is coming from down low/underneath center. Even 2nd & 3rd gear under slow rpm it does this up to 4,000 or so. No I am not lugging it. The chain is tight, maybe just a lil over but if looking at chain it still runs up and down while doing this. Seems to more way more than when I use my hands. Setting still with brakes locked I would let in and out on the clutch to see if the engine was possibly rocking backward, but it does not seem to be. Is everyones engine extremly close to the H-Pipe as in 1/4 to 3/8"? Any advice would be greatly appreciated. Oh, by the way, it has a loud rattle when accellerating through the first 3 Gears, and probally more but can't notice due to noise/wind.

[The CyberPoet]

(A) Check your chain again, this time to see if it's stretched beyond it's wear limits. Lifting off at the center rear of the rear sprocket should get you under 1.5mm (OR LESS) if it's still reasonable; more than that and it's toast (note the picture shows about 12mm of elongation as a total exageration for effect). My guess is that your chain is bad and that your cush drive pads desperately need to be replaced as well, based solely on your statements.

From: CyberPoet's "Understanding Motorcycle Chain Wear and Maintenance" webpage:


(B) Learn to slip your clutch more and use your throttle less. You should have maybe 1/8th throttle or under when pulling away, and get that engine up to 5k before the 1st-to-2nd shift, 6k for 2nd-to-3rd. Driving below 4k RPM is pretty much lugging it on your engine (which makes it's peak torque around 8450 RPM).

(C) Check for loose items, such as the horn bracket, the oil cooler supports, the gauges and the windshild. These things can come loose and will rattle at lower RPM's enough for you to notice.

Good Luck!
=-= The CyberPoet

[97GSX600F]

Thanks alot! You may have solved my problem!It is too late now but I will find out in the morning. Went out to the garage to check the cahin as shown in the diagram. Hmm. Can get any play at all, like it is welded to the sproket! 3 days ago I noticed my chain was very, very loose. Upon inspection I noticed my keeper was misssing from axle nut, and my tire was about 1/2" from hitting my right arm! Major cockeyed! I tightened my chain bolt, and re-inserted a keeper. Man that chain seems way to tight now. Maybe I was half asleep when I tightened it?

[The CyberPoet]

Maybe. You should have about 1.0 to 1.1 inches of slack in the chain as ideal (this is from the Kat owner's manual):


If your rear wheel was off-kilter, it would explain everything.

BTW - if the chain is stuck to the rear sprocket, that's good, not bad. 1.5mm is the maximum it should be able to be lifted up before replacement.

Good Luck!
=-= The CyberPoet

[blackkat98]

Doh! I read the title and thought this was a question for Sue Johannson on The Sunday Night Sex Show!

[md86]

Pre's are the same slack-wise as the 98+ ? My book says 1.2-1.5" for the 750's .

[The CyberPoet]

Pre's are the same slack-wise as the 98+ ? My book says 1.2-1.5" for the 750's .

If your owner's manual says 1.2 to 1.5, go with it. That graphic above is from the 98+ owners manual.

Cheers,
=-= The CyberPoet

[97GSX600F]

Thanks guys. I just got home from work and rode the bike to and from with no problems, except the horrible rain here in Ohio! I loosened it up to the specs above and drives like new again! Thanks everyone!