Anyone Know The H/p Output For The 450&the New 650 Xr Motor?

[MR.EX-TREME]

i just got a another 2000 400ex with a blown motor . i thought i might try a transplant either the new 450 or possibly a 650 xr motor and i was wondering what the horsepower was stock on these two motors? or a third possibility in my copy of the new bike trader they have an 1996 ktm MX620 dirt bike for sale for $1950 what about that motor? thanks guys!!:devil :confused:

[Wheelie]

The CRF450 puts out 55hp at 9000rpm, and 36lb-ft of torque at 6000. In a quad chassis the XR650L pumps out roughly 49hp to the rear wheels.

As for the 620, I have no clue.

[MR.EX-TREME]

thanks man-that will help me decide!-ive been hearing the ktm 620 is hard to keep tuned and is not that great of motor!! thanks again ----later-man:devil

[RideRed04]

dont throw out the ktm 520 or maybe ktm's 380 2-stroke.

[MR.EX-TREME]

yeah i found an ktm 520 bike for $3200
and an crf 450 for $4850
decisions --decisions--lol
how about the height of the 520? ive heard its to high for an stock ex frame? keep up the response!! thanks:devil

[R-Crazy]

it looks like a TALL motor. I like the CRF. i want to put one of those in a quad chassis.

dave

[optikid123]

some frame companies make custom frames to fit prettymuch any motor i think lonestar houser and a few others

[punker69q]

I think the xr 650 is the best choice, cuz 50hp at the rear wheels compare to 55hp at the engine for the crf450, and the 450 engine will be more "peaky" and you can modify the xr650 engine quite alot (probably something like 70hp+) I saw a 650ex on the net and this quad reached 94mph

650ex (http://www.atvillustrated.com/feature_articles/trx650ex/article.html)

[MR.EX-TREME]

COOL THANKS GUYS I COULD PICK UP THE 650 A LITTLE CHEAPER ! I'LL PROBABLY GO TO ALL THE TROUBLE TO PUT THIS TOGETHER AND IT,LL BE EXACTLY WHAT HONDA COMES OUT WITH FOR THEIR NEW QUAD!!! LOL:devil

a stock XR650 puts out about 43hp. But that's with all of the emmisions stuff, and it is running a 128mj. compare that to the already lean 148mj on a 400ex. Honda has a power-up kit which has a larger exhaust tip, intake manifold(twice the size as the stocker), and a few other things to make it breath. it is the most choked up dirt bike on the planet. put a 170mj, and all of the other unkorking mods and it makes over 50hp, and a gargantuan amount of torque. it was designed to run "unkorked", but so it could be green sticker legal, it was leaned down, and a bunch of intake and exhaust restrictions were put in.

that xr650 quad article said it meets or exceeds ds650 and raptor performance levels in an understatment.(unless it was running in bone stock form-43hp) It should kill both of them unkorked, and that's with a stock exhaust. In the dirt bike world it is said to be faster than a cr500, and kx500 2-strokes. I know in theroy, the 2-strokes would be faster, but owners of the 650(ex owners of the 500's) claim the 650 is quicker and faster,
just with an even powerband. It is a reliable engine as well(most hondas are) That would be my engine of choice.

Thats becouse the cr500 and kx500 use mid 80's tech. The new 250 bikes are about as fast as the 500.

[MR.EX-TREME]

GREAT IT SOUNDS LIKE THE 650 ENGINE MAY BE THE BEST !! THERES A GUY AT THE DUNES THAT RIDES A NEWER XR 650 WITH A PIPE AND SOME MILD MODS AND A PADDLE TIRE ON THE REAR HE BEATS ALOT OF THE SOUPED UP BANSHEES UNTIL HE GETS INTO THE ONES THAT ARE REALLY BUILT!! SO THE MOTOR WOULD PROBABLY DO GOOD IN AN EX !! WONDER WHAT THE WEIGHT DIFFRENCE IS IN THE BIKE AND THE EX?:confused: :devil

are you talking about the whole bike or the engine? The bike is about 280lbs dry, and of course the ex is 375 dry. the XR motor is 88lbs dry, and the ex motor is 92lbs(according to my service manual) keep in mind the big 650 is liquid cooled, so that's an extra few lbs.

[Z400central]

and remember, kick start to....but i think the biggest thing would be 1. exhaust, 2. fabricating the parts like the engine mounts and something about having the engine line up with the axle....

[RideSportrax]

Go wit the XR650 Motor. Its less peaky than the CRF, and has much more torque. The CRF motor is great dont get me wrong, but honda tunes it to about its max (55 hp). The XR motor is like wheelie dude said, very corked up! If you do mods like he says the XR motor will easily outpower the CRF.Why? CC'S! The 200cc difference in displacement means a lot! Good luck with the transplant and let us know how it comes out!

[MR.EX-TREME]

THANKS FOR ALL THE HELP I WILL LET YOU KNOW WHAT HAPPENS--LOL!!