Best Sprocket Size

[brazilian rider]

Anybody can answer me wich is the best size for rear and front sprockets on a 400 EX that do trails and cross countries?And for MX and BAJA??PLEASE I NEED SOME HELP

[ChadEXer]

Stock gearing is best!!

[EvilJester400EX]

if you don't have a built motor, use 14-38 (i believe that is stock rear size). but if you have a built motor (high comp. piston, 406, 416.. etc) stock gearing would be fine. for the woods i ride, i needed the 14t front sprocket because 2nd would be too high of a gear, and 1st was too low.

[Braff1]

The stock sprocket size is 15 front/ 38 rear.

If you ride wooded trails or for cross country racing I strongly recommend using a 14 T front sprocket. This will give you bottom end coming out of turns and for climbing hills.

For MX racing you will have to use a trial and error method. Here are some pointers to help though. 1) if the track is tight with lots of turns go with the 14T for bottom end in coming out of the turns. 2) if the track is spread out, open, you could use a 15 T this will give you more top end.

Baja- I have never raced but I would have to say 15 even possibly a 16T.

[chavez]

i switch depending on the tires i ride between 20inch tire 15 tooth and 22inch tire 14 tooth and 38 tooth rear

[Sparks425Ex]

For Mx I run one of two things. My quad had to much torque with stock gearing so I had to go to:

15/36

or somtimes run

16/38

The 15 gives me a little more torque for shorter tracks.

[brazilian rider]

I should go with the 15T cause I'm always in trails, the cross countries here are speedy and I do some enduro/baja
What about the rear?Should I go with the 38T?

[SuperEX]

15 and 38 is the stock setup, I plan to go to a 14 & 38

[cjpoole1]

heres a helpful chart to figure sprocket ratios. A little tip is that 1 front tooth is pretty close to three rear teeth so if 1 tooth on the front is to much or too little, you can fine tune it with 1 tooth more or 1 tooth less in the rear.

[ChadEXer]

I will be running 14/38 on mine for drag racing and stock for all other riding! I dont think taller gearing is wise on a 400EX unless you are racing on roads or a long ways!! Sidewinder tried to get me to go up on the rear instead of going to a 14 on front(because your drive system will last longer that way) but its much easier to change the front Sprocket at the track than the rear so i went with the 14 up front for drags. These Sidewinder "Ti-Moly" chains are aweseme!!! They are expensive, but they are rated at 14,000# tensile strength(way ahead of anyone else) and Packard, Twister, and SanDragon and all those guys with 150-200 horsepower machines run them and they dont even stretch!!!

i like 14/38 for MX

[400exRacerX]

14/38 for mx?? Well that would work if you wanted to top out at 50mph.

For MX (which meens you are running 18 inch rear tires) the best setup i think is 15/36.

[ill_lil_romey]

For mx, with a torquey motor 16/38
For tight twisty trails, or supercross or arena cross type tracks 14/38
Stock gearing works great for many different applications.
In my case thought, with the torque of my motor, and 18 inch rears with 20 up front, the 16 tooth countershaft is a must for me. The 18 inch tires make up for the slight lost in bottom end, and you end up with a nice, feel that will accelerate quickly , and pull all the way to the top without flattening out. I'm very happy with my 16T.

[RIDER11X]

14/38 WORKS GREAT IN THE WOODS BUT YOU WILL BE SMOKED ANY TIME THERE IS A CHANCE TO OPEN IT UP IN A FIELD OR SOMETHING. I RUN 15/38 FOR THAT REASON- BUT I AM CONSIDERING A 15/39-40 COMBO TO FIND THE RIGHT BLEND.

Originally posted by 400exRacerX
14/38 for mx?? Well that would work if you wanted to top out at 50mph.

For MX (which meens you are running 18 inch rear tires) the best setup i think is 15/36.

well right now i have the stock tires and no engine mods thats why. when i get the 18's i will go back to stock gearing then when i get mods i will get a 36 rear. also the tracks are real tight:D

[Baley69]

What about for the dunes?