I am pretty sure you have to buy the whole bike. If I were you, I would try and find one of those nuts that do the hillclimbs with the hills that are almost 90 degree angles. They sometimes swap engnies so you could buy the bike, yank out the motor, and sell the rest to one of those crazy A$$ ****'s.

 

Engine builders are not engineers they can build up low power engines into full race engines, but are they reliable? Companies like Honda or Suzuki build their motors to tolerate a certain amount of stresses. While you do say the DRZ engine is over-engineered. I just cringe at the idea of doing an engine swap and then also having to build up a motor that could possibly turn into a grenade. When I can buy a machine that is already putting out big time horsepower stock, and designed by engineers instead of motor builders.

Adam Smith

99 400EX

02 CRF450R

 

heres my point about using the drz motor, in dirtwheels mag a couple years ago they were interviewing yamaha engineers who were working on the raptor; they asked them why they did not put the 426 motor in a quad chassis. The engineers responding by saying that the 426 wouldn't hold up over time, it is fine for a raced quad that gets rebuilt all the time, but it would not be relieable in a quad. When the crf came out, atvaction mag interviewd them and asked when we were going to see the 450ex, honda told them that the 450f motor was not enginnered to be put in a quad and that it would not hold up over time. Now as far as we know, the z400 motor is the same as the drz400 motor, except the pipe, carb, and transmission is different. This would infer that the drz motor would be a better candidate for a fast, reliable quad. Also in dirtrider mag the suzuki engineers said that when they designed the drz400 motor that it was originally designed to use a 436 bore, but that they decided that for an enduro/trail bike that the 400 was more than powerful enough. so far there have been no reliability issues with thumper racings/yoshimura's 436/470 kits at all during last seasons gncc series.

 

I think the numbers were measured at the rear wheels. check out the new Feb Dirt bike mag. 40hp for drz, 46hp for wr426(unkorked), which is on par with the yzf. I drove a stock DRZ400 and was supprised at how much power it had. it would totally flat out smoke my 400ex(it even has some mods) and I personally think it would beat a semi built banshee or raptor. Put a pipe and filter(with jets) on the drz, and it is suppost to be a lot faster. It is as quiet as a stock 400ex( which is extremly quiet for dirt bikes apparently) so once unkorked, it flies! it'l hang with a 426 in a drag race. 80-85mph is the stock top speed for the drz400. it has been a reliable motor for the dirt bike, but has weak engine cases(not as big of a deal in a quad) and the valves need to be checked regularly(one of the intake valves seems to get out of adjustment sometimes, many bikes experience the same thing)

I don't know where I read it, but I read that the crf can beat a 426, and several people on dirt bike forms admit to having crf's beat them on their 426's(drag races). who cares, there both fast.