440 Bottom end

[patrick delao]

I just finish puting in my 440 kit and I went with a wiseco 11.1 and a xr head gasket which is only .025 and a XR cam. I have killer mid and top but the the bottom end isn't what I thought it was going to be. I have a 40 pilot with the screw 3 turns out the needle one clip down and 168 main and I am at 5600 feet. HELP K&N also no lid and I tried 175 main to break it in and it runs better with a 168 so far.

[The400exExorcist]

wow...I figured you wouild be complaining of no top end....the xr cam & 440 are made for bottom end, try those jets again..

[patrick delao]

the XR cam is a mid to top cam and the stock 400EX cam is a bottom end cam, but the 440 with 11-1 should give me the bottom end I'm looking for but ?

[400exJOE]

heres my 2 cents. I think with a 440 I should run mine with a 170 main jet and I am close to sea level. Since I am going right to a jetless carb I can't be certain. But the main jet is low for the low end. And at 5600' elevation, it should be even richer I believe. Start with a 170 and work your way up. that should solve your problem.;)

[MIKE400EX]

Pat, the XR cam is NOT a top end cam - mostly midrange. That 440 combo should have loads of bottom and mid(way more than stock), top will still be much improved though. If the bottom is worse than no mods check and make sure the cam isn't retarded a tooth. A 42 pilot will help alot too.

[R-Crazy]

try just upping the clip on your needle. then check your spark plug. if that doesnt help, try screwin around with how much air you getting into your motor. you may be runing too lean(or really rich).

dave

[oynot400]

I had the same problem with mine, it just didn't seem to have much of a bottom end. After I got it wound up it ran great. Well about a week after I had my engine work done, it blew out my s/a. So I contacted FMF and they sent me a new one, free of charge!:D Anyway I ran the hole race season with out it thinking that a free flow exhaust was the way to go. I was wrong as soon as I installed the new s/a I had my bottom end power again.
That is just something to check, as far a the jets I would check the plug and go from there.

Hey oynot400 what does s/a stand for?

If your positive your cam chain alignment is correct, then it should be your jetting. Did you mover you needle clip down? You will want to go with a richer main jet also.

[MIKE400EX]

Probably his bikes spark arrestor:confused:

[oynot400]

Yes s/a = spark arrestor. Sorry for the confusion.

[patrick delao]

Guys thanks for the info. I went down on my main from a 175 to a 160 and it helped alot I was way too fat and the other thing is I'm at 4 turns out on the pilot. What do you think atleast a 42 pilot??? Plus Mike I degreed the cam 4 degrees advance for more bottom end. The bottom end is ok but I think there should be more.

[badass400ex]

if your timing was one tooth off it wont start right? im just curious one of my friends has the same prob i have a stock 400 with a yosh slip on and his bottom end is about the same as mine i have stock gearing and he is -3 on the rear witch would be the same as going up 1 in the front

[MIKE400EX]

Yes, unfortunately they will start, and you risk bending valves, piston damage etc... Just didn't want someone to risk that kind of damage - especially since its so easy to check!

[patrick delao]

Mike I went up to the 42 pilot and 2 turns out and it woke it up HUGE. So much I went up on my gearing from 14/38 to 15/39 it pulls stock gearing great but we hill climb and I wanted a little more low then stock and a friend gave me a Talon 39 so I tried and still have not put alot of time on it but I seem to like it. We will see after I climb with it. THANKS for all the help. One more thing I wonder since my bike has so much mid If I can go another clip on the needle and raise it somemore or is that too much for a 440 even?