chain & sprockets

[Nero-92]

the s4 is nearly due for chain & sprockets so I was wondering which manufacturer should I bye and more importantly the size of sprockets as when in traffic 1st gear is hunting and 2nd gear is to low and top speed is really academic for me as there are no roads any where near me that I might possibly do 140 mph so any advice would be much appreciated.

[Speeddog]

I'm running a 15/39 on my S4, but I do quite a bit of freeway riding.

15/41 is pretty good for more around town riding.

Go steel rear and 525 to get best life.

[NAKID]

For that bike, why wouldn't you go with a 520? It doesn't really have the power to need a 525 and stepping down to a 520 combo saved my S2R1000 4 lbs of rotating mass!

[Speeddog]

525 lasts longer; ~25% more wear area on pins, bushings, rollers and sprocket teeth.

How did you save 4 lbs?

A complete 525 S4 driveline (chain with front and rear steel sprockets) weighs ~6.5 pounds.

[DonJuanDucati]

Usually rear chainwheels for 520 chains are aluminum, there's a good amount of weight lost going from steel to aluminum, but no, not 4 lbs. More like 1.5-2.

[NAKID]

You know what, it's been a while so yeah it was probably closer to 1.5 or so. Not sure where I got 4lbs.

Now that I think of it, the final weight of the chain, front drilled sprocket, and rear alum/steel rear sprocket was right around 4lbs...

[Scotzman]

So, would the "525 best life" concept be applicable to a 695 as well or is the lower cc less of a factor?

[DonJuanDucati]

I had a DID 520 x-ring chain with Renthal aluminum rear sprocket. The chain didn't stretch much, but the picture below is what happened to my chainwheel. On my 900, I think a 520 chain is fine, the problem is with aluminum sprockets. To be honest, that's where most of your weight savings will be though is in using an aluminum over a steel sprocket. There's only a few ounces saved going from a 525 to 520 chain. Either way though, I think a 695 would be fine with a 520 chain.



That's after about 5k miles and two track days. 

[NAKID]

That's why I went with an aluminum sprocket with steel teeth.