Stock gearing on a 99 YZ250?

Anybody knows what the stock sprocket sizes (front and back) are on a 99 YZ250?

I bought my bike used a few years back, and it feels very short in 5th gear.



My 99 yamaha service manual states that it is 14/50.

That seems about right. I was looking at an online part schematics and they list

14/49 as standard.

Big Hal, 13/48 sounds odd. Is that what you have on your bike?


13/48 is effectively that same gearing, but the smaller front sprocket will wear quickly as will the chain slider. Its best to go 14/50.


I run 14-49 on tight tracks and 13 on open sandy tracks.

ive used from 13-15 front and 42-49 rear it all depends what and where your riding. You dont need to go 14/48 on a track where you may never see wide open 4th so i change mine to suit the top speed that ill be doing so that i get the most out of the motor. When i go to Mammoth ill run a 13 front to help since the air is thin and power is down due to high elevation and it helps as you can take tight corners in 2nd and easy corners in 3rd. Its all about using the best gearing to get the motor rpms where you need it.

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