total mechanical amateur - Clunking noise when accelerating? Any Ideas

If I try to accelerate at anything other than a snails pace in first or second the bike makes a loud clunking noise and it feels like the chain is skipping.

Is it likely to be caused by a lose chain? I'm confised by this 20-30 mm of slack idea as it's very lose when on the sidestand, but totally tight when I sit on the bike and move it aginast the gearbox.
(I know nothing about bike mechanics!)

just went out for a closer look and the top part of the chain is resting on the swingarm and has dug drooves into it. See these pictures.

http://img229.imageshack.us/gal.php?g=030dhl.jpg


What's going on here??

It's going in for a service on Thursday but as I ride it to work every day I'ma bit worried it might be something that needs to be sorted straight away?

Bike is SV650S K5 - done nearly 11000 miles

You need a new chain, son. That's probably the worst condition chain I've EVERR seen..

A lesson to be learned here in looking after your chain.

That chain's rusty and dry because it hasn't been looked after - you should lubricate your chain at no less than 150-200mile intervals. It only takes a minute or two to do, and will prolong your chain life no end.

That chain is also, I would say from the small amount I can see, too slack - The chain slider (black rubber bit on top of the swingarm) is there for just that - for the chain to slide on - but when it's becoming as gouged as it appears, that would suggest the chain is running constantly on the slider.

Have you ever lubricated your chain? How long does a chain last for you on average?

If you are lazy, get a Scottoiler fitted. They will allow you to almost forget about chain-care, as it seems you have done already!

Originally Posted by TechJinx

If I try to accelerate at anything other than a snails pace in first or second the bike makes a loud clunking noise and it feels like the chain is skipping.

Is it likely to be caused by a lose chain? I'm confised by this 20-30 mm of slack idea as it's very lose when on the sidestand, but totally tight when I sit on the bike and move it aginast the gearbox.
(I know nothing about bike mechanics!)

just went out for a closer look and the top part of the chain is resting on the swingarm and has dug drooves into it. See these pictures.

http://img229.imageshack.us/gal.php?g=030dhl.jpg




What's going on here??

It's going in for a service on Thursday but as I ride it to work every day I'ma bit worried it might be something that needs to be sorted straight away?

Bike is SV650S K5 - done nearly 11000 miles

Looks like it's not seen any lube for many a mile.
Treat the bike to a new chain & sprockets and oil it a plenty.

Not worth messing with stiff links!

I too know nothing about bikes but the two things I do know are look after your chain (lube it frequently and clean when you can - otherwise the grit you pick up off the road with rub against the chain) and check your oil. If either of those things aren't watched they can go horribly wrong! Works out either painful for your pocket or far worse, very painful for you.

[yorkie_chris]

Originally Posted by Jamiebridges123

You need a new chain, son. That's probably the worst condition chain I've EVERR seen..

Amatuer!

Some of the locals round here would reckon that chain jsut about broken in... in fact I'll give mad Roy a shout and see if he wants it for his CBR...


The clunk is probably the chain slapping around. replace with a quality item and fit a scottoiler.

[Red Herring]

Have you checked the front sprocket? If the teeth are worn out it won't matter how tight the chain is, they will jump on acceleration and make the sound you describe.

Originally Posted by Red Herring

Have you checked the front sprocket? If the teeth are worn out it won't matter how tight the chain is, they will jump on acceleration and make the sound you describe.

+1
a worn chain can cause excessive wear to the front sprocket! my mate left his fazer unchecked with a dodgy chain and one mornin he tried to set off and ended up with a large washer instead of a sprocket! was amusin to see when it came off!!

that chain is awsome!!!!

on a silimar note i get a clunk when changing down. Any ideas what that could be. Only happens below 4k revs tho

Your Gearbox? :P