A forum for owners of Yamaha TTR250 trail and enduro bikes!

Marshall · Veteran Member

Front sprocket making a noise

TTRfan · Super Guru

Is it rubbing on the case saver confuse

Marshall · Veteran Member

i dont know what the case saver is, but from what i can see its not rubbing on anything unless its inbehind were i cant see.

TTRfan · Super Guru

The case saver is the shiny part close to the chain. It is supposed to save the crankcase from damage if the chain breaks.

Marshall · Veteran Member

hmm no i dont think its hitting that unless it is behind the sprocket, i have not done everything to check the problem i just wanted some ideas one what i should be looking for.

TTRfan · Super Guru

Can't think what else to suggest - sorry!

PS Check your chain slider - green rubbery thing in the pics that protects the swing arm - coz it looks like the lower front end may be worn. If it is and you leave it then the chances are the chain will start to chew into your swing arm and its bearing cap.

Haggis Hunter · Veteran Member

Hi Marshall

It looks like you have a new or fairly new chain fitted. If so it may just be the links are a wee bit tight and are not engaging with the teeth on the sprocket correctly. If you can see no sign of rubbing anywhere it's the only thing I can suggest. I have had this happen on my bike with a new chain and sprockets but once it had done a few miles and the chain had bedded in it was fine.

Hope this helps

I should have said that if the chain has been run with another sprocket for a while it would have worn to the old sprocket. If Fitting a new sprocket to an old chain it will take a time to bed in. I tend to get through 2 front sprockets to 1 chain and 1 rear sprocket.

Peter

-- Edited by Haggis Hunter on Thursday 25th of April 2013 12:56:28 PM

TT-R250M · Super Guru

From the vid it does not seem like a problem at at.

Mine sounded like that when new too.

Jarrah

Cubber · Super Guru

It sounds as if the new chain is creating the noise as it bends from the straight run onto the 13 tooth sprocket.

If so then it's a normally expected noise that will undoubtedly diminish as it is used. smile

Small sprockets bend the chain run to a smaller radius/tighter curve which many reckon exacerbates wear of sprocket and chain.

Run it for a while but keep checking it.

Martyn

Marshall · Veteran Member

Cool thank you guys this helped allot .

KMAN · Senior Member

I got a similar prob,

Done a few klm's and is stil there, have ground a bit of the case saver, but is still hitting on a closed throttle ( i know dont close it).....
Bike has a 2 inch lowering kit, does this cause a prob or could the chain b a little slack, bike has only app 100k on the clock.

cheers k

Marshall · Veteran Member

No idea, i know that mine is hitting somwhere and i cant find out where. Pissing me off LOL its just a millimeter on the chain too, the chain is dirty but a millimeter on the top and bottom of chain is nice and shinny just cant see it.

TT-R250M · Super Guru

I find that using a larger rear sprocket ie. 50, 51, 52 it tends to rub a little more than usual. My problem was the chain slider cover retaining holes needed to be elongated. It still ''slaps'' the rear chain slider on the REALLY bumpy sections though hmm

When I carry a passenger (double) it hits the front case saver just slightly. I am unsure where exactly it hits though. I did see something about this ages ago, think it was Brian having the same trouble but I could be wrong?

Jarrah