Rattle in Gearbox

[Arven]

Hi Guys,

I have an 1994 GSXR 750. When i take off at low rev's the gerbox makes a loud rattling / clicking sound. It only does it under load at low revs. And it will do it in any gear.

I have been told it might be Clutch rattle, but its alot louder and more violent than what people have usually heard...

Anyone got any other idea's of what i could look at?

Thanks for the help.


Arven.

[merv]

Is the sound in time with engine revs or road speed and does it change as you change gear?

I only ever had one bike make clicking sounds and it only did it in third gear because it had lost a tooth off one of the gears used when in third. That only happened because a screw came loose off the stator on the alternator and it ended up going between the gears and getting mulched - bent the mainshaft a bit too and knocked the tooth off.

So I'm thinking you may have lost a tooth but if its in every gear it would have to be off one of the primary drive gears.

Does the clutch feel OK? Not slipping or anything? Usually they only rattle under no load when the bike is in neutral and the engine is idling. Except Ducatis with dry cluthces that sound like a loose tin of bolts at the best of times.

[Marmoot]

If you're totally sure it's in the gearbox, try changing the oil and see if it helps.

If you're not too sure yet, it might just be the cam chain tensioner is out.

I believe (someone correct me if I'm wrong?) camchain problem noise is more evident in low revs (especially idle), while gearbox problem noise is more evident in high load/rpm.

[Arven]

Naa, I don’t think there is a tooth missing. It does it in ALL Gears, and only when under load. I haven’t noticed if its in time to the engine or anything like that, if I park up, and put the front break on, and start releasing the clutch while in a high gear, it will start to do it really loudly.

So I'm hoping its going to be a Clutch tensioner or something like that rather than a gearbox problem itself!!

Yea! Camchain! Now somebody said it sounded like that also! any more info about that i could look into???

Cheers for the help guys!

[Arven]

What bikeshops in Auckland do you guys recommend? I have only ever used Mt Eden and they have ripped me off too many times. Anyone recommend any other places???

[Marmoot]

Originally posted by Arven
only when under load.

U sure it's not detonation/knock/ping?

Btw, Cyclespot is quite nice. I used them for the last 4 years. Have a talk to them.