15 tooth C/S sprocket

[betoney]

I got my 15 tooth C/S sprocket installed this morning and took the bike out for a test ride. HUGE improvement over stock gearing, just like on my FZ1, I feel that going down 1 tooth up front is how it should have been delivered from the factory. Starting off from a dead stop at stop signs/lights require much less throttle input to get moving, infact you can just slowly let out the clutch and start rolling without even touching the throttle if you choose. You still have plenty of powerband range in each gear around town without revving too high, you just shift slightly sooner and each gear feels more effective. Getting on an interstate on-ramp is much the same, plenty of power to rev out each gear and 6th feels much more useable cruising at 70mph where the rpm is raised about 300 rpm.  
(I would normally keep it in 5th and only use 6th above 70-75mph)
 
The only downside is Yamaha doesn’t have an OEM 15 tooth rubber dampened sprocket and aftermarket has a slight whine you can hear if you have your visor open while slowing down. Though, the slight noise is VERY MUCH acceptable given the increased rideability. If you were to mainly focus on long distance highway riding then I wouldn’t bother, but in tighter conditions where you might want a closer ratio gearbox then I consider it a “must have”.  Worst case, if you hate it then you are only out $28 + $6 S&H.
 
Sprocket Center Superlite Sprocket
 
 

[bruceintucson]

Nice to know they're now available. Tried to order one a few months ago and no one had the 15T. Another slight advantage is it lengthens the wheel base a little.

[Brick]

Nice to know they're now available. Tried to order one a few months ago and no one had the 15T. Another slight advantage is it lengthens the wheel base a little.

 
Only if you use the same length chain. ?
 
I'll have to think about this change. Might just do it.

[bruceintucson]

Did it effect the speedo error? Too lazy to go into the workshop & look at the SM to see where the speedo sender is driven from.

[betoney]

Did it effect the speedo error? Too lazy to go into the workshop & look at the SM to see where the speedo sender is driven from.

When I got my bike new, I did a speedo test with a GPS mounted to my bars, accuracy was within 1-2mph.  I did the same today after switching to the 15T and it was still off by 1-2mph. 
I'm not sure where the speed is detected from, on my previous FZ1, I originally had to use a SpeedoDrD to correct the inaccuracies.  With that bike there was also an option to correct it as part of the ECU flash.
 

[bruceintucson]

Did it effect the speedo error? Too lazy to go into the workshop & look at the SM to see where the speedo sender is driven from.

When I got my bike new, I did a speedo test with a GPS mounted to my bars, accuracy was within 1-2mph.  I did the same today after switching to the 15T and it was still off by 1-2mph. 
I'm not sure where the speed is detected from, on my previous FZ1, I originally had to use a SpeedoDrD to correct the inaccuracies.  With that bike there was also an option to correct it as part of the ECU flash.

Nice to know, thanks. Guess I'll get that 15T ordered for Mary's FJ and not tell her when I change it.... :-) 

[betoney]

If you ever find a rubber dampened 15T from another model that fits let me know. I would think most output shafts "should" be the same dimensions? Maybe I am way off here.
While the whine on the non-dampened sprocket isn't horrible by any means, it is noticeable. In 20,000 miles or whenever its time to swap out the sprockets and chain, I may try 16/47 (+2 rear) as it is almost the same ratio and you can use the OEM dampened sprocket.

[fattraxx]

I changed to a 15T several months ago,very happy with the results. Speedo seems to be reading about 6-7 mph fast.

[betoney]

I changed to a 15T several months ago,very happy with the results. Speedo seems to be reading about 6-7 mph fast.

Ya know, I believe there must be some production variances between bikes.  I have read posts on here of people claiming 6-8mph variance when compared to a GPS, while others (myself included) experience much more accurate results, 1-2 mph variance.  I'm not really certain how or where the speed is detected on this bike, but there seems to be a large margin of error  between bikes. 

[duhs10]

I changed to a 15T several months ago,very happy with the results. Speedo seems to be reading about 6-7 mph fast.

Ya know, I believe there must be some production variances between bikes.  I have read posts on here of people claiming 6-8mph variance when compared to a GPS, while others (myself included) experience much more accurate results, 1-2 mph variance.  I'm not really certain how or where the speed is detected on this bike, but there seems to be a large margin of error  between bikes.

The variance reported here was after changing the gearing so that is to be expected.
 

[2and3cylinders]

This has been discussed before. Going from OEM 16/45 to 15/45 = 6.6% change "lowering" gearing (higher numerically). Going to 16/47 is a bit less at 4.36% change "lowering" gearing (not as high numerically). 16/49 = 8.88% change "lower". A 15 tooth CS sprocket stresses the chain due to the smaller radius it must follow more than a 16T and of course stepping up in the rear has no negative effect on the chain but it would need to be determined if a larger rear sprocket is available (and keep the OWM 16T front with its damper but I've never heard a whine going to an AM CS sprocket as mentioned on other motorbikes in the last 40 years but I guess it's possible) and at what size larger tooth sprocket a longer chain would be required. I doubt a 47T would be an issue. On the other hand, a smaller front may run the chain out of adjustment (at least with the OEM adjusters and has anyone tried one of the AM adjuster assemblies?) when it wears (there's no such thing as chain stretch) down the road (pun intended).

[bruceintucson]

This has been discussed before. Going from OEM 16/45 to 15/45 = 6.6% change "lowering" gearing (higher numerically). Going to 16/47 is a bit less at 4.36% change "lowering" gearing (not as high numerically). 16/49 = 8.88% change "lower". A 15 tooth CS sprocket stresses the chain due to the smaller radius it must follow more than a 16T and of course stepping up in the rear has no negative effect on the chain but it would need to be determined if a larger rear sprocket is available (and keep the OWM 16T front with its damper but I've never heard a whine going to an AM CS sprocket as mentioned on other motorbikes in the last 40 years but I guess it's possible) and at what size larger tooth sprocket a longer chain would be required. I doubt a 47T would be an issue. On the other hand, a smaller front may run the chain out of adjustment (at least with the OEM adjusters and has anyone tried one of the AM adjuster assemblies?) when it wears (there's no such thing as chain stretch) down the road (pun intended).

The biggest sprocket JT Sprockets lists is a 46T rear. Don't think a 15T front would be as hard on a 525 chain as say a 530 chain, but know where you're coming from. As far as "running out of adjustment with the stock adjusters", it's only an ordinary M8 bolt and you could replace with a longer (or shorter) bolt with no issues. And don't think even if a 47T rear was available you could get the axle/adjusters that far forward with the stock 110 link chain; the axle is already so far forward that the marks on the axle side pieces barely even come into play with the marks on the swingarm. Think 15/45 is probably what Yamaha intended the FJ/MT/FZ to be geared with initially with the 110 link chain. Would have increased the wheelbase a little (good thing). Why they didn't install a 112 link chain with the 16/45 is beyond me. 

[redfjniner]

This has been discussed before. Going from OEM 16/45 to 15/45 = 6.6% change "lowering" gearing (higher numerically). Going to 16/47 is a bit less at 4.36% change "lowering" gearing (not as high numerically). 16/49 = 8.88% change "lower". A 15 tooth CS sprocket stresses the chain due to the smaller radius it must follow more than a 16T and of course stepping up in the rear has no negative effect on the chain but it would need to be determined if a larger rear sprocket is available (and keep the OWM 16T front with its damper but I've never heard a whine going to an AM CS sprocket as mentioned on other motorbikes in the last 40 years but I guess it's possible) and at what size larger tooth sprocket a longer chain would be required. I doubt a 47T would be an issue. On the other hand, a smaller front may run the chain out of adjustment (at least with the OEM adjusters and has anyone tried one of the AM adjuster assemblies?) when it wears (there's no such thing as chain stretch) down the road (pun intended).

I got a whine when I replaced the OEM sprockets, along with install of my third chain.

[peporter]

This has been discussed before. Going from OEM 16/45 to 15/45 = 6.6% change "lowering" gearing (higher numerically). Going to 16/47 is a bit less at 4.36% change "lowering" gearing (not as high numerically). 16/49 = 8.88% change "lower". A 15 tooth CS sprocket stresses the chain due to the smaller radius it must follow more than a 16T and of course stepping up in the rear has no negative effect on the chain but it would need to be determined if a larger rear sprocket is available (and keep the OWM 16T front with its damper but I've never heard a whine going to an AM CS sprocket as mentioned on other motorbikes in the last 40 years but I guess it's possible) and at what size larger tooth sprocket a longer chain would be required. I doubt a 47T would be an issue. On the other hand, a smaller front may run the chain out of adjustment (at least with the OEM adjusters and has anyone tried one of the AM adjuster assemblies?) when it wears (there's no such thing as chain stretch) down the road (pun intended).

When the time comes to replace my sprockets and chain, I'm going to a 520 16-45 setup, with a 110 link chain. Should loose a few pounds also. And, to the naysayers, I did this conversion on my DL1000 V Strom, and it worked a treat. No adverse wear issues at all, and a noticeable acceleration improvement.  https://www.drivesystemsusa.com/superlite-rs-series-sprockets/yamaha/street/fz-09-14-15/ 

[2and3cylinders]

When the time comes to replace my sprockets and chain, I'm going to a 520 16-45 setup, with a 110 link chain. Should loose a few pounds also. And, to the naysayers, I did this conversion on my DL1000 V Strom, and it worked a treat. No adverse wear issues at all, and a noticeable acceleration improvement.  https://www.drivesystemsusa.com/superlite-rs-series-sprockets/yamaha/street/fz-09-14-15/ 
2and3cylinders said:
 
I've run DID ZXVM 520 on my very comparable power output (+ 2 HP & 10 FP) VTR and they last about 5,000 miles less (only 18~20k miles) than the otherwise identical DID 530 and that's with fairly careful maintenance and a Scott Oiler(BTW, I also always run steel sprockets F&R, yet to try a SuperSprox rear).  Yes less unsprung weight and faster spin up (less rotational mass) but NOT really THAT noticeable.