2nd gear knocking in small rev range, any ideas?

[extreme601]

Hi everyone.

I searched around and couldn't find any information directly related to a problem I've got with my new FZ6, however I might be wrong so I apologise if this is a repeat thread.

The engine makes a knocking sound in 2nd gear whilst accelerating between 4 and 5k revs. Speed of the knock is about 1.5 a second and stays very consistent in it's speed but only lasts for a few seconds until the revs are above 5 thousand.

I'm not very mechanically minded so any advice as to what the problem could be would be greatly appreciated.

Thanks in advance!

 

[RJ2112]

How many miles are on the bike? How many miles are on the chain and sprockets?

My first guess would be a kinked chain.... what sort of condition is the chain in? Any rust, or stiff links?

 

[extreme601]

27,000 miles on the bike. Unknown mileage on the C&S but the wear on them is minimal from memory. I'll go and take a look at the chain now.

Thanks very much.

 

[extreme601]

Hi again,

You're absolutely right, there are a couple of slight kinks in the chain, I gave them some pressure and the links won't straighten out at all.

Can this by fixed with a thorough clean and re-lube or will it need to be replaced?

I really appreciate the help, thanks!

 

[greg]

might be time for a change i'd say

better to spend a little now, or risk your chain snapping and ripping your gearbox/leg/swingarm to bits

 

[Norbert]

get new chain.
27,000 miles is about the right time for a new one.
you can't "un-kink" it.

 

[extreme601]

That's fine. I'll get it done.

Thanks all!

 

[RJ2112]

That's fine. I'll get it done.

Thanks all!

If the chain is bad, odds are good the sprockets have seen better days, as well. Wear on a sprocket is pretty subtle... but it will chew up the replacement chain at an accelerated rate compared to a new set of sprockets.

Better to swap out the front and rear sprocket as well as the chain as a set.

 

[Motogiro]

In addition, if the chain is that worn the chances are that the "O" rings are also done and wouldn't hold the internal lube.

 

[Motogiro]

might be time for a change i'd say

better to spend a little now, or risk your chain snapping and ripping your gearbox/leg/swingarm to bits

I was just reading someone had a chain snap and it jammed up the rear wheel and the bike high sided.

 

[Norbert]

I was just reading someone had a chain snap and it jammed up the rear wheel and the bike high sided.

would a front sprocket cover like this protect your engine case and leg.....?
i've seen dirt bikes that have them in case the chain snaps. i'm not sure how effective something like this would be, though.....

 

[greg]

I was just reading someone had a chain snap and it jammed up the rear wheel and the bike high sided.

i saw oine guy on another forum have his gearbox completely destroyed when his chain snapped at highway speeds, luckily he didn't come off

 

[RJ2112]

would a front sprocket cover like this protect your engine case and leg.....?
i've seen dirt bikes that have them in case the chain snaps. i'm not sure how effective something like this would be, though.....

When a chain snaps, and wads up in front of the front sprocket.... that's when it punches a hole in the cases.