Sprocket Teeth????

[pre-game]

well i have been riding my 99 cr250 now twice since the fresh motor, and im just not pleased with the amount of power i am seeming to get out of the bike,. i mean its better than ever before, but im really looking for that scary fast feeling like everyone first felt hopping on a 250. that feeling like your arms could be ripped out of the sockets!! anyways the bike is set up with a 13/49 sprocket combo, stock for my bike is 13/50.. i got a little ballzy and decided to go with a 13/51 tooth, i am not really concerned about top speed but i do want that bottom end, wheelie ripping power... i never rode the bike with a stock setup...

anyone else running a setup with an added rear tooth? what do you guys run,?? i mean the sprocket was cheap enough i can always go back easy enough, so i figured i would give it a try..

 

[dirt bike dave]

The sprocket will make a noticeable difference in pep, but you will find you are shifting more often and can't hold first and second gear for as long. This may or may not make a difference where you ride.

FWIW, I had a '99 CR and the motor is smooth and controllable, with good low end power and little hit for a 250 MX bike. This is great for trail riding and many MX riders are actually faster with the smoother power delivery.

But lots of riders like a more explosive power delivery, as it may feel more fun even if you don't ride any faster.

If you want more explosive power delivery, a cylinder and pipe from a '97 or '98 CR250 will make a big difference. If you can find someone who wants to swap (many riders prefer the '99 porting and pipe), it won't cost much if any money. The '01 cylinder is also a direct swap and has more radical porting than your '99, but the '01 frame is different, so the pipe mounts are not exactly the same).

If you swap jugs, expect shorter ring life and more fuel consumption. The mildly ported '99 is pretty good in these areas.

If you can't find anyone to swap cylinders and pipes with, porting your cylinder and an aftermarket pipe can change your power delivery dramatically.

Basically, porting and pipe will make a bigger difference than the sprocket.

 

[FruDaddy]

Try a v-force reed cage and an aftermarket pipe, jet the carb, then drop to a 12 tooth front gear.

 

[Deadohiosky39]

This may seem like a dumb question but what kind of shape is your rear tire in? If it's shot then it may just be spinning so much that is feels slow. It's just a thought. Either that or the jetting might need to be cleaned up a little bit

Like they said you might try a different pipe. And if you put the 12tooth sprocket on with the 51 it might be too much. I was thinking that one tooth on the front was about equal to 2 or 3 on the back. I could be wrong. So that would be like running a 13/54. Seems like your gears would be way too short then.

 

[pre-game]

thanks guys, i just rebuilt the motor(new jug, piston, head, crank) but the bike has an fmf fatty, the tire is brand spankin new also, i just built the rear wheel with new hoops.. i think my jetting is off slightly, i have to adjust my slow jet something fierce... but im getting ready to go out and try and conquer that in a minute once this Fla rain finally stops.... damn hurricanes.. thanks for the help everyone

 

[dirt bike dave]

My '99 had a '97 carb and ignition, and it was very sensitive to airscrew adjustments. Even an 1/8 of a turn would make a noticieable difference. I think you might be able to tune more of a 'hit' by playing with the airscrew. If your summer air is hot and humid, you might need to back out the airscrew compared to what you run in winter.

 

[whenfoxforks-ruled]

How is your clutch? Does the oil stink? Stock gearing or 1 up in the rear, as long as the clutch is solid.

 

[pre-game]

the plate thickness was decent when i checked them, the manual shows i got some time left to burn on them before i need new ones.. i adjusted the idle and shes runnin alot better, for some reason she was wanting to keep going like i had a stuck throttle, but thats all cleared up now, she screams... but i can always go for some sore arms.. :ride:

 

[whenfoxforks-ruled]

Sore arms is another story. Do you have steel plates in your clutch? Are they colored? Good reeds, new muffler packing and jet it.

 

[NJGregsCR]

I agree with DirtBikeDave, I would play with the airjet settings. My 97 CR is sensitive to any airjet tweaks. I changed out to the 13/51, but mainly because I use it as a woods bike, and combined with the flywheel weight servs the purpose well.