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TRXRIDER4567
06-20-2007, 11:55 AM
how fast does a stock kfx 400 go

mx825
06-20-2007, 12:01 PM
mid 60's??


sorry, i'm guessing.:p

TRXRIDER4567
06-20-2007, 12:04 PM
do you know any one with one.
i was asking for my cousin
do you know about a stock trx 250 ex

07250ex
06-20-2007, 12:08 PM
stock 250ex is about 50, stock z400/kfx400 is about 66 ish

TRXRIDER4567
06-20-2007, 12:10 PM
thanks alot

TRXRIDER4567
06-20-2007, 12:11 PM
how about a kfx all stock with a fmf slip on

07250ex
06-20-2007, 12:12 PM
no prob

400exfan19
06-20-2007, 12:16 PM
Originally posted by TRXRIDER4567
how about a kfx all stock with a fmf slip on
i dont think it changes very much, i think it just gives it more power

TRXRIDER4567
06-20-2007, 12:36 PM
i have a trx 250 ex i wanted to put 20 inch tires on over the stock 22 what would happen

07250ex
06-20-2007, 12:40 PM
well techinally:
22'' tires the speed is said to be anywhere between 50 - 54
20'' tires most people claim 50 i would say probably 47 but you would rap out a lot quicker also you wouldnt gain top speed with an hmf on a kfx you would add torque and a lil accel

TRXRIDER4567
06-20-2007, 01:12 PM
thanks again
also does a 20 inch tire slide better than a 22 inch.

YFZ450Ridr
06-20-2007, 03:02 PM
way back when i had a 250ex i put 20s on it and it was a whole lot better for the woods but it topped out so fast, it would have been lucky to hit 45 realisticly. a new pipe or filter wont give you any more speed. you get more power, better throttle response, and faster acceleration. you still have the same gearing and revs so top speed is not affected. a stock 250ex will do 50mph give or take a few, this is proven with a radar gun and dyno graphs ive seen. a stock z400 or kfx400 is just shy of 70.

TRXRIDER4567
06-20-2007, 03:05 PM
yfz rider would you suggest the 22 or the 20 for trail and track riding (jumps whoops trails)

YFZ450Ridr
06-21-2007, 11:59 AM
i would go for a set of 21s actually. i never rode on 21s but i did with 22s and 20s and i think 21s would be perfect for it. kenda makes a knarly xc that is 21 inches tall, check that one out!

07250ex
06-21-2007, 12:41 PM
even if you do get aftermarket 22's they will be better then stock like a razr or razr 2 will still provide better accel and sliding because of the increased traction and im pretty sure reduced weight? but 20's wills by far increase you accel it will be like droppin a tooth up front you'll rap out quicker but it will feel faster as well as accel faster

TRXRIDER4567
06-21-2007, 02:38 PM
07250ex would you suggest the 22 over the 20. for ground clearence reasons also will a 20 slide better in the corners than a 22 inch.

400exfan19
06-21-2007, 02:57 PM
Originally posted by TRXRIDER4567
07250ex would you suggest the 22 over the 20. for ground clearence reasons also will a 20 slide better in the corners than a 22 inch.
hardly effects ground clearance and a 20 will slide better

YFZ450Ridr
06-24-2007, 12:15 AM
Originally posted by 07250ex
even if you do get aftermarket 22's they will be better then stock like a razr or razr 2 will still provide better accel and sliding because of the increased traction and im pretty sure reduced weight? but 20's wills by far increase you accel it will be like droppin a tooth up front you'll rap out quicker but it will feel faster as well as accel faster

a 22inch razr 2 would dog down a 250ex so much. the lugs are so big and being a heavy tire that bike would have a hard time pulling them at that height. any after market tire is heavier than stock simply beacause of the ply. ply is the thickness of the tire in general which plays on the tires rigidity and puncture protection. i have razr 2s all around on my yfz and they are not a light tire by any means!

also being that the 250 is shaft drive, even with 18s it would still have plenty of ground clearance.

mojavedude
06-24-2007, 04:38 PM
Originally posted by YFZ450Ridr
ply is the thickness of the tire in general which plays on the tires rigidity and puncture protection.

ply is actually how much steel cord is in the tire. tires are not only rubber but have steel cords in them to help the tire keep its shape.

http://www.yourdictionary.com/images/ahd/jpg/A4biaspl.jpg

but your right, more ply is more puncture resistant and makes it heavier. most mx tires ar 2 or 4 ply so its light and xc tires are 6 ply for puncture resistant.

07250ex
06-24-2007, 04:47 PM
you can get 20 inch razrs that are 15.4 pounds doesnt sound very heavy

03KawiKFX400
07-08-2007, 10:59 PM
Originally posted by YFZ450Ridr
way back when i had a 250ex i put 20s on it and it was a whole lot better for the woods but it topped out so fast, it would have been lucky to hit 45 realisticly. a new pipe or filter wont give you any more speed. you get more power, better throttle response, and faster acceleration. you still have the same gearing and revs so top speed is not affected. a stock 250ex will do 50mph give or take a few, this is proven with a radar gun and dyno graphs ive seen. a stock z400 or kfx400 is just shy of 70.
Ive had mine toped out...I didnt realize i was moving that fast.