New sprockets needed??

[Red-Duc]

Im just about to order a new chain which has done over 6000 miles and is worn out, the sprockets have done the same mileage but look ok, would it be advisable to renew the sprockets aswell?? if so what make would be best to go with, its got renthal ones at the moment

[DC]

Its always best to renew the chain and sprockets in one hit. The Sprockets that you have now may look ok but may well wear out quite quick after putting on a new chain. May even affect your new chains performance??

If putting a new chain on old sprockets was a quick fix for example, say to get you home after a breakdown then yes, but not as a rule.

As for what make? Renthal seen pretty good to be honest. If in doubt, give them a ring etc.

DC

[andys 900ss]

Yep, same here Red-duc.

I replace all of them to be sure they get even wear.

Renthal are the best in my eyes and they do hard-anodised ali rear sprockets which give good wear for mileage.

Let us know what bike/year/gearing you currently have and I'm someone will advise any alternatives. My suggestion would be 14 tooth front sprocket for good acceleration for little loos in top speed.

Andy

[Zimbo16]

I'd replace the lot. I usually get mine from B&C Express, Renthal sprockets and Tsubaki chain, prices are excellent.

[Red-Duc]

The 900sl is standared gearing i think 15 front and 37 rear, Think that im gonna stick with this as i cant afford to lose any topend

[phoenix n max]

http://www.talon-eng.co.uk/

Although as one of my customers I pay slightly less for them. I like em :)

I can get you a costing if you like ?

Oh and i've had a Tsubaki chain for the last 4 years including 2 seasons ( ish ) racing.

[ziggi]

http://www.BandCExpress.co.uk

I would definately recommend getting 39T rear sprocket. You'll hardly notice the top end difference but you'll get there quicker. Renthal sprockets and a Gold Alpha X ring Tsubaki chain. About £95 in all.

[Red-Duc]

Think I may go with a 15 front and 39 back then, How longer should the chain be from standard to take the bigger sprocket??

[ziggi]

Dunno but the items I bought from B&C express above were fine for 2 teeth up on the rear.

Incidently, at 100mph my revs are exactly 5500rpm with 39T rear sprocket. See what your revs are at 100mph with 37T rear and I bet they will be only a few hundred lower at most. I can still pull 140mph (althought that's maxed out).

** Note: all the above figures were carried out in a controlled off-road environment by professional riders :D Please don't attempt to copy any of the sctunts on this message board.

[Red-Duc]

Hi Ziggi
Thanks for that, I will check the revs next time i go out which should be this week if its fine

[Red-Duc]

Been out for a ride tonight, Rpm is 5500 at 100 mph with a 37 rear sprocket, Looks like i should go with the 39t rear.


opps forgot to mention, test was done on a private road

[Iconic944ss]

Interesting - tried it the other day 100mph = 5600rpm on a 41T rear :devil:

I told the officer I had to try this test out for DSC purposes!

Cheers - Frank

[Red-Duc]

Frank what front sprocket you using?

[psychlist]

When you're comparing speed/revs on bikes, make sure you really are comparing like for like. Quite a few changes were made to primary drive ratios through each models life.

[Red-Duc]

Not sure what the other bikes are but ive got

97 SL MK5 15 front 37 rear and at 100 mph pulling 5500 revs

[ziggi]

Ah! Now I've also got a 170/60 section rear tyre (newish Pirelli Diablo). I reckon a 180/55 section rear tyre would affect it somewhat also.

Interesting all the same

[Iconic944ss]

Paul has a very valid point about final gearbox ratio's

Red-Duc, front sprocket is a std 15T I believe.

Frank