Gearing (14/48-13/48)

I have an 02 Rm 250 and im just deciding to jump the front tooth up one(from 13 to 14) and the rear is knocked down already(from 50 to 48, which the previous owner did)... anyways i wanna know how much it will affect the bike? 1st, 2nd, and 3rd gear 2/4 to 3/4 throttle the rpms are redlining and the front wheel is coming up, it just dont pull enough(as in, rpms raising and having to shift)... i feel like im not getting the most i can out of the engine, i woulda hate to have ridden it on 14/50, i just feel like theres and emptiness after 3/4 to wide open throttle, roosting on a straight away... im not worried about bottom end, im worried about top, ive heard bigger gear in front and smaller on back will increase top end, and smaller in front and bigger in back will increase low end.

Thanks for any help.

I have an 02 250 also. It has 13/50 gears and I like it. I do mostly trail riding so that works good for me. If you do more top speed riding, it would cost less to go to a 14 front sprocket and if you don't like it, you didn't loose that much. With the 48 on the rear, I would think it would make a big difference in lower rpms because the motor will struggle to get up to speed. That's what I found with my bike. Even at mid rpm's it seemed to slightly struggle to get to top speed. Maybe struggle is the wrong word, but with my 13 on the front, it pulls hard no matter what rpm I'm at.

Did you check the jetting? Maybe it's too rich on top that is holding it back from 3/4 throttle on? And yes, big on front and small on back gives it more top speed.

You are in sand and pine trees ??? Right ???

Or track riding ???

13/50 should be stock....that is where the transmission is designed to pull the stock sprockets.

14/48 ...Yes on a paved road , you will go very fast 5th gear topped out.

But in the woods/or track.....the motor will struggle to pull the 14/48 ratio....

Of course someone else , will post the exact opposite of what I just typed, in about 5 minutes.

But , I have a 05 model , with a 13/49.....and at last weekends race , that was deep sand , and pretty much wide open fields.......I still feel like I needed the stock 13/50 ratio.....after looking at the race results...lap times........just wasn't getting the torque to pull out of the deep sand , as other racers..........even though it seemed like I was hauling a$$.

On another note the 13/49 or 48 sprockets does make the bike run smoother.....less arm jerk.....I never went with the 14 front..........seems a little over the top.

But there are sprocket ratio can google to ...give you more detail , on making an informed decision.


Because you are only changing the front sprocket, you will not have to worry about the chain length and the front sprocket is way cheaper than a rear sprocket. So go ahead and try it (14/48 gearing). It will definitely have a higher MPH (Miles Per Hour) in every gear and have less of a hit, but it will just take "slightly" longer to get to the max rpm in each gear.

I say ~ go for it. For you and where you ride it "might" be perfect.


i just noticed i was riding 14-49

never had any trouble on the track, and ow yeah my rm250 is from 91

and ow yeah my home tracks are very heavy sand. The only thing was that some corners it just didnt have enough power to take it in 3rd, and if you shift back to 2nd than and get on the throttle it's like horse on the run :smirk:

ive tried 14 front, had to grind away a tiny bit of the rubber thingy on the swingarm, no big deal . for my riding i have settled on 13 50 or 13 51,

i found with the 14 i was not pulling from very low in 2nd even with the fww, but i do mostly woods and am in 2nd and 3rd gear a lot before blasting into top

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