yz400 hp rating

6 replies to this topic
  • tmeyer37

Posted September 05, 2008 - 01:36 PM


Does anyone happen to know the Horse power rating for a 99 yz400f. Ive got one and im just curious what the stock rating for the bike is. I was thinking somewheres around mid 50's but im not sure


Posted September 05, 2008 - 01:54 PM


im not sure but i know the 450s are mid 50`s, so if i was a betting man id bet an ol 400 is pumping out low 40`s

  • grayracer513

Posted September 05, 2008 - 02:48 PM


An '06 YZ450 produces just at 50 RWHP (stock). An '08 puts out at 52, an '03 around 47, a good 426 does around 46, and a 400 is at about 44, according to the best charts I can remember.

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  • rdefonce

Posted September 05, 2008 - 03:46 PM


I second Grayracer's numbers. That's in the area of a 250 smoker, but where the 400 dominates is TORQUE! That's why the 250 smudge pots were out-gunned by the 400's.

  • yz007f

Posted September 05, 2008 - 07:32 PM


Grey is right on the numbers I dyno'd a stock 04 at 46hp and I had a 03 at the time with a few mods at 50.

  • NorCal

Posted September 06, 2008 - 03:33 PM


Hey Gray, if the new CRF is claimed at 56.4 horsepower, how much do you think
it would put out at the rear wheel?

  • motojoe_23

Posted September 07, 2008 - 07:18 AM


Was just searching around for some other stuff, and came across an old Motorcycle.com article saying 43hp

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