4th Gear Kit 25T/25T MSX/SF Yuminashi

4th Gear Kit 25T/25T MSX/SF Yuminashi

With the 4th gear 25T/25T sports gear set, you transform the original gearbox with overdrive, into a close-ratio transmission with a 4th gear in a sporty ratio of 1:1.

On 125 motorcycles, you can install a 16-tooth front sprocket, which will lengthen the 1st, 2nd, and 3rd gears, and most importantly, a 4th gear that immediately gains speed for a higher top speed in 4th gear than in 3rd.

With the change, you will get an engine that will run at a lower temperature, capable of withstanding a higher compression ratio and, again, without any drop in performance when shifting from 3rd to 4th gear

You also get a significant reduction in engine knocking (detonation).