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The TTR250 FAQ web pages -> TTR250 -> Repairs and maintenance -> Sprocket wear and front sprocket guard bolts
Post Info TOPIC: Sprocket wear and front sprocket guard bolts
Lumbricus


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Sprocket wear and front sprocket guard bolts
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Hello people.

I was going to adjust the chain on my newly bought 2003 TTR but thought that it may in fact be worn beyond repair.

I measured the 10 link distance as recommended in the manual, which suggest a wear limit of 150.1mm. It was pretty much 151mm. But then I read that someone elsewhere (I can't remember where) that mentioned his chain was 151mm when new. I was confused.

The chain was also making a horrible, gritty crunching sound and could be pulled quite a bit away from the rear sprocket at the 3 o'clock position. I was thinking of replacing chain and both sprockets.

My first question: Do these sprockets look worn to you?

 

 Front sprocket wear 1.jpgFront sprocket wear 2.jpgRear sprocket wear.jpg

 

My second question: Where can I get replacement front sprocket guard bolts? I think the service manual suggest they are 'M6' but I'm not sure now. Could I use the same bolts for the started gear cover offered by Brian? http://www.ttr250.com/TTR_extras/index#cover_bolts

 

Thanks in advance for all help...

 

Rob



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TT-R250M


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Hey Rob,

The sprockets really don't look all that bad and seem to have a few more miles yet. I cannot tell you off hand what the wear limit is for the chain, maybe Brain can help with that. If you are concerned it would be best to replace it. 

The sprocket guard bolts are M6, any good hardware or fastening store should stock these, if you have trouble finding them, use eBay.uk- http://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=M6+bolts&rt=nc&LH_PrefLoc=1

Jarrah



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2000 TT-R250M-

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buffalo4


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Hi generally if the chain is adjusted correctly
Try pulling it away from the rear sprocket
If you can then it is ready for replacement
HTH
Ian

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chrisstdt


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When the chain is stretched alot the sprockets will show as the teeth will start to bend because of the wear in the chain

I prefer allen head bolts they tend to be easier to get out (i dont use allen keys i use hexagon bits and a 10mm spanner) if there tight you can put the bit in the head and hit it with a hammer ! this usualy helps them crack off easier and makes sure the bit is in the head of the bolt properly so it doesnt slip but if you put grease on the threads and dont over tighten them they should be fine in future



-- Edited by chrisstdt on Tuesday 19th of November 2013 08:30:13 PM

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Lumbricus


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Thanks for the replies guys.

What is the best type of head to choose for the bolt? The ones I took from the sprocket guard were bolts with a crossheaded slot in the top. The crossheaded screwdriver was rubbish in trying to get them out and I was only saved by using a 10mm socket.

Even though I plan to use copperslip and not to do them up too tight, I am worried they may eventually seize and an allen head bolt will get rounded when trying to undo them again.

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Lumbricus


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Thanks for all the help!

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