S2R 1000 gearing / sprocket selection

[hillbillypolack]

Though this may have been discussed ad nauseam (and I did do a search before posting), I wanted to ask a question about re-gearing the S2R 1000.

I know stock gearing is way way too high with the 15t front and 41t rear.  I dropped the front to a 14t, and am looking to return to a 15t front when I do a 520 chain conversion.  The equivalent gearing for a 14t/41t when moving to a 15t front is 15t/44t.  However, as the bike is geared with the 14/41, I find that I'm in riding situations where I'm needing to downshift just to keep the engine where it needs to be (rev wise).  The bike wants to be on the boil with at LEAST 4500 rpms, but is coming into its sweet spot just under 5000.  Highway revs are between 5500 and 6200 depending on traffic flow, though I'm not often riding the slab except the rare workday commute.

The question really is if a 45t would be 'too much' gear.  And if there is anyone who has tried the 15t front / 45t rear combination.  Is there adequate clearance for the sprocket to the swingarm?

Thanks in advance for any input.

[rockaduc]

I don't know about the clearance issue, but I can tell you that you won't notice any difference going the equivalent of 1 tooth up in the rear chain ring.

[stopintime]

Check out and play with GearingCommander

15/45 is not good for sprocket wear. And it's under 2% difference from your 14/41.
For this combo, you'll also need a longer (new) chain.

14/42 is hopeless regarding wear.

14/43 is ok (4% higher revs at all times), but you still need one chain link more.

My 0.02: learn to control the bike with what you've got now and/or have it tuned to run smoother.

[He Man]

I don't know about the clearance issue, but I can tell you that you won't notice any difference going the equivalent of 1 tooth up in the rear chain ring.

I can. i went +1 in the rear and noticed it. it was tremendous, but defintely noticeable.

[hillbillypolack]

Check out and play with GearingCommander

15/45 is not good for sprocket wear. And it's under 2% difference from your 14/41.
For this combo, you'll also need a longer (new) chain.

14/42 is hopeless regarding wear.

14/43 is ok (4% higher revs at all times), but you still need one chain link more.

My 0.02: learn to control the bike with what you've got now and/or have it tuned to run smoother.

I know I will need a longer chain (hence the conversion to a 520 section chain), and I am hoping it will rev higher, since the DS twin isn't even breathing until it gets into the mid 4000s.  The bike has a DP ECU, and exhaust and still has the characteristic off-idle hiccup despite my riding Ducatis and tuning them for 20 odd years.

Can you please explain your take on sprocket wear?  I am returning to a 15t front, which is optimal for both chain run efficiency and chain tension (reducing tension by +/- 9% from a 14t).  That's why I'm adding to the rear sprocket to gain (lower) the final drive gearing.  Sprocket wear should be a non-issue with that combo, but I could be wrong. . .

[hillbillypolack]

I can. i went +1 in the rear and noticed it. it was tremendous, but defintely noticeable.

Just curious, what size ring are you running in the back?  (sprocket size).  14 or 15t front?

On my M900, I dropped a tooth in the front, and added two in the rear, but I'd only be adding to the rear on the S2R.  Thanks.

[He Man]

I am running 15 up front, and the rear is stock +1, im not sure if it was 39+1 or 41+1 i cant remember.

I wouldnt recommend going just +1, its noticeable, but it leaves you wanting more. +3 is way too much in my opinion, and +2 should be perfect. I didnt do 14 up front because i bought a new chain at the time and rather do +1 in the rear than make the front any smaller.