12T front sprocket bad?

I have a 2006 WR250F and I am wanting quicker acceleration. Right now it is 13/52 (stock). I am trying to decide if I want to go 12/52, 12/53, 12/54, or keep the 13 in front and just change the rear (to 53 or 54). A deciding factor is if dropping a tooth in front will cause wear problems...? Also, I have read somewhere that you want an even and odd number of teeth, rather than both even or both odd. Is this true?

A change of one in froint is sort of like three in back

Too small a front sprocket does but excessive stres on the chain. 12 is really too small.

Odd and even teeth means nothing

I'll put on a 12T for a super nasty tight off-road even/ride, but take it off and slap on a 13 and the rear sprocket suitable for my weight, riding style and ability.

I also have an 06 WR250f and my sprockets are now 13/50. Final drive ratio is calculated by dividing the number of teeth of the rear sprocket by the number of teeth of the front one. So yours is stock, 4.0, mine is lower than stock, 3.85, which give me a bit more speed at the high end. A 12T fron t would give you a 4.33, which might make the 1st gear obsolete.

I read at some point that the best mod for what you want is putting a 12T. I have one and plan to try it when replacing the front sprocket next time. It would probably wear off the chain slider and the chain faster, but I would not care at that point.

Do you have the other mods on the bike? Mine is pretty peppy when I rev it up, and it is pretty forgiving at low rpm when in the right gear.

I have the AIS removed + appropriate jetting, grey wire and extra holes int he air box.

I have an '08 and have been running a 12T front and 50T rear for about 2 years now. We ride mostly single track that I'm in 2nd gear a lot for. 1st is nice for a quick, steep uphill, but I haven't had any problems. I do keep an eye on it, and have replaced my chain slider and chain guide in the rear once in 3 years....

Cool thanks all. Does any know the ratios for the tranny gears (First - Fifth) on a 2006 WR250F?

Edited by rritt31

I found them in the forums as comparison to YZ, ca't seen to find them now

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