440 messed up

[RUFIO]

Riding on sunday I draged my friend new 440.

Hes running the 440 kit from wiseco with a white brother cam, Mega Max II (powerbomb), Stage 3 K&N (filter, neddle, clip..ect.)

Im runnng a Sparks x-4, 155 main jet, UNI filter, and open box. The rest of my motor is stock.

Now im going into this expecting to be destroyed but the first run he only beat me by 1/2 quadlengh, and the second time I beat him by a full quad lengh. Is this all 440s do? I was reaaaaaaaly dissapointed because i wanted to put his setup on my quad but after seeing what little it was doing idk about it anymore..Does anyone know what could be wrong with his quad or suggestion of another kit for me?

[RUFIO]

I told him i thought it had alot to do with his pipe not flowing enough for the 440 and/or the cam timing was off. :rolleyes:

[Mxbubs]

HHHMMMMMNNNN.......Is he heavy?

[RUFIO]

lol no, and hes alot more experianced than i am

[KY Woods Rider]

Three things come to mind immediately: rider, traction, length of the drag race.

You said that he was a more experienced rider, so that may not be the problem. However, I've seen many experienced trail riders (who don't routinely practice starts) that couldn't get a quad to launch off the start correctly if their life depended on it. If you don't mind switching quads, try a few runs on the other's machine and see what happens.

Rear tires, swingarm length (which for arguments sake I'll assume are the same), and shock setup could all make a difference in traction. Even with equal setups the 440 will likely break loose spinning easier, which can make a fast quad look terrible in a hurry (horsepower ain't no good unless its getting to the ground).

The length of the race could change the results dramatically too. Depending on what gearing and engine setup (built for top-end, bottom-end, or midrange power) your friend is running, you might have found the distance that his quad isn't set up for. Try shorter and longer drag races and see what happens.

[F-16Guy]

A couple of common things:
1) If he used a Wiseco piston for his 440 and didn't have any machine work done (besides the bore and sleeve), the compression ratio is most likely way lower than what it's advertised at-- do a search for "have you decked the cylinder", it explains what the problem with the Wiseco 89mm piston is and several different approaches to correcting it.
2) Lots of people equate more fuel with more power. Have your buddy install a 42 pilot jet, and start going down on his main jet. If he sees an improvement after the first size down, keep going down until no improvement or until it runs worse, then go up one. Stage 3 sounds way rich to me. The richest setting in the stage 2 kit was way too rich for my 416, and it breathes very well.

[nakomis0]

I was thinking the same as F16guy about the Wiseco kit..

or the jetting not dialed in right