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3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 1:29 am
by Dobbie
My bike has a 39 tooth rear sprocket fitted and it has been jacked up at the rear slightly higher than standard but this has combined to cause the chain to destroy the chain guide and start to eat into the swing arm in a relatively short space of time. What do you think, would a 45 tooth rear sprocket sort it or would you just go for a new chain guide. Trouble is I like the way the bike rides for road use with the 39 tooth on it. Anyone got any ideas or a decent guide??
Re: 3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 2:19 am
by zimm
bigger sprockets front and back to space the chain out and keep the final drive ratio you like.
Re: 3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 10:02 am
by Motorcycle Solutions
You should be on standard 16 front and 48 rear matey you can go to the lowest of 14 front and 41 rear i beleive,....
Re: 3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 1:02 pm
by Dobbie
Thanks a lot for the info. Ebay here I come!
Re: 3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 3:45 pm
by Motorcycle Solutions
Dobbie ebay no good got to this address :D
http://www.arracing.co.uk/anr.nsf/viewc ... +Sprockets
and go down to fzr400 rrsp don't worry about the year for they fit my 1989 model... better to go for 520 pitch chain (i can supply one for £50 posted and 520 sprockets they will last longer.. get direct from a & r racing...
http://www.arracing.co.uk
http://www.arracing.com
one of these will work
Order from these for this is where i get sprockets from and they are light weight renthals
To order the chain goto
http://www.lajracingservices.com and fill the booking form in and in the top colum put mail order
Re: 3tj Chain cutting into swing arm
Posted: Tue Jun 03, 2008 6:09 pm
by oldgreg
Use this table to work out which sprocket combination will give you the same gearing you have now.
http://shop.wemoto.com/info.dyn?title=S ... ear_Ratios
For instance, if you have a 39th rear and a 14th front your ratio would be 2.79. You could then keep very nearly the same ratio by using a combination of 48th rear 17th front (pretty much the biggest set available).
I'm running 45th renthal rear 14th afam steel front which is magic off the line (front wheel comes up just a little on the power in 1st

) especially now that i've refitted the EXUP (thanks again for that Chris :D ).
That said it does rev at about 7.5k when i'm cruising at 60mph
I got my bits from A R racing - Good money, and they were very helpful.
Re: 3tj Chain cutting into swing arm
Posted: Wed Jun 18, 2008 10:19 am
by Dobbie
Spoke to wemoto and got a standard 19 front and 55 rear and izumi 428 chain £42 and that's with postage, o.k. it's not o ring but for what it gets used it'll do. I also got a new chain runner from a local breakers for a tenner. just need to sort the tension issue now :)