sprocket change-what to go with

[rynb15]

my 400 is a dog in 4th and 5th gear in a wide open run. it seems like it takes forever for it to get to full speed. the bike runs great. i think im just used to my last bike that was a 660 raptor. my gps says my top speed is 60mph. I ride a lot of woods and its fine there. but the place i ride is full of wide open land for a few miles as well. what would be the best sprocket combo to gain acceleration? i dont mind losing a little top end. i can barley get to it now. i have 20inch rear tires as well.

[a4guy]

If you have a 14 tooth right now and you want a lower top but a faster acceleration then go to a 13 tooth front sprocket. Also going with a smaller rear wheel will help too. Maybe try and 18" tire and leave the sprocket alone.

[JOHNDOE83]

depending on your tire and sproket combo, that will happen, I can hit 70mph in 4th gear and still pull all the way through 5th, but I have extensive mods.

What size are your sprokets now??? and mods you have??

[rynb15]

ill have to double check but im almost positive they are stock. i have 20 inch tires now. i had 18s but they sucked in the trails. for mods just a lexx slipon, no lid on the airbox and a rejet.

[MO-EX-RIDER]

go down 1 tooth up front to see if you like it, i went 1 up in the rear and it is perfect in the tigh stuff but still runs good in the fields

[slightlybent47]

this may help

http://home.earthlink.net/~gellett/400ex.htm

[clemsonteg]

yeah you are with the 15/38 on the 04. try going to a 14.

[sickmojave]

if you are running stock sprockets and 20" tires. it sounds like you may be a little rich on the top end. what jets are you running?

[honda400ex2003]

Originally posted by sickmojave
if you are running stock sprockets and 20" tires. it sounds like you may be a little rich on the top end. what jets are you running?

my thoughts exactly. that is too slow for a 400ex ever. lol. a 155 main with needle in the middle, 38 pilot and 3 turns out on the f/a screw, should do nicely with your lid off and the lexx.
I would guess that you have around a 160-162 in there now, which is too rich imo. I like a 14 tooth for the real tight stuff also, i think it would be a nice addition for you. steve

[rynb15]

i have a 155 and a/f screw 2.5 turns out. overall the bike seems to run perfect. the wide open areas im talking about are sand. maybe that makes it harder on the atv.

[honda400ex2003]

sounds like you are good. the sand really makes a lot more drag. i would now suggest 14 for sure. steve