Speed question?

[Warrioreater400ex]

ok, this has just been bugging me for a while.... i know top speed really doesnt matter that much, and i know there are a lot of variables, but i ride with two other 400ex's a 99 and an 02, both have stock engines and pipes, one is really ragged out, mine has a E-series slip on and a k&n filter and supposed jetting, thats what the guy i bought it from said was that it had a dynojet kit in it, anyways you would think i would be faster than the two stock ones, however that isnt the case, not only am i not faster, i am SLOWER, on top end and mid range, i have more torque, but thats about it, i have the stock 15/38 gearing and so do they, are some just faster than others????

[JOEX]

Over all weight makes a difference.... including rider, added accessories, tire thickness ans size.

The pipe and jetting wont neccessarily make you faster, it just gets you to the top speed sooner.

Joe

[Cody_300ex]

Also Wb E-series pipes are tuneable with discs. I think its the more disc the more bottom end, And the Less discs the more top end. But dont take my word on that and please corect me if im wrong.

[BBW]

Hmmmm, I have a very similiar set up as you with the WB e-series, K&N filter, and 155 main. That is until recently when I started running with the airbox lid off and went to a 165 main.
I did a lot of racing up the dunes against stock 400's and those that weren't stock and have been able to beat most everything. Top end however I haven't really tried. I believe I have 12 discs in which most definantly makes a difference. If in doubt on the main jet I would pull it and see what size it is. It takes about 5 minutes and there are about 10 billion threads in here on how to do it. To answer your question, YES, there are some identical machines that are faster than other. My son, my nephew and I all bought new 400's a few months ago and stock mine could consistantly beat the others regardless of the rider. I guess everything just goes together more exact in some than others. The other thing that could play a role is break-in which I wouldn't touch with a 10 ft pole. Some say ride em hard and some say break em in easy.
Top end it's kind of a given what's faster but if your racing over a short distance I would swap machines with the guy that's beating you and see if he still beats you.

[cals400ex]

tighten your throttle cable so there is only a little more than 1/8 inch of play in it. this makes a big difference if it isn't adjusted properly.