Only a couple 59T sprockets left. We have replaced these with our Superlite RS8 Series 415 Rear Sprockets.
415 Aluminum Rear Sprocket
The rear sprocket is made from the highest grade aluminum aerospace quality 7075-T651 and weighs 13.2 oz. It is hard anodized to reduce wear and increase durability.
18t/55t and 18t/56 are close to the stock gear ratio for the Yamaha R3 (stock 14/43 gearing). 57T and 58T will give you excellent drive off the corners and great starts and work well with a lot of tracks.
If you are mid pack and still getting faster, I recommend starting with a 58T rear sprocket which works very well for most tracks and most rear tire sizes. If you are already at podium pace and challenging for the win, I recommend starting with a 57T. Then make changes up or down from there as necessary.
Available in 54t, 55t, 56t, 57t, 58t, and 59t rear sprocket sizes.
When using an 18t front sprocket, use the following as a guide for chain length:
54t – 142 links
55t – 142 links
56t – 142 or 144 links
57t – 144 links
58t – 144 links
59t – 144 links
Changing from a 520 size chain and sprockets to a 415 chain and sprockets on the R3 makes a significant performance improvement.
I specifically dyno tested this upgrade to prove the difference. These 2 dyno runs are done back to back (about 20 minutes apart, as fast as I could pull the wheel and change the chain and sprockets) with the same bike, settings, dyno, tune, everything identical, and in the middle of the day after lots of other runs so the bike and dyno are hot. These are each the best of 5 runs to be sure everything was even. You can clearly see that the 415 kit improved power to the ground by .62 hp and torque by .29 ft lbs and improved performance across the entire power band.