440 Question

[2001400ex]

I've been looking at getting a 440 kit for Christmas for my 400, I have plans for getting a lot of things and this is next on the list, I was looking at all the companies that make the 440 kits for the 400EX and the first two that I saw were these. I got them from the links section of this site. I am wondering why there is such a huge price difference between the Trinity 440 kit, and the Wiseco 440 big bore kit. The link won't direct you to the Wiseco 440 big bore kit that I found on www.rockymountainatv.com but I do have one that works for the Trinity.

Trinity - http://www.trinityracingproducts.com/44bigborkit.html

Is the difference between the prices the fact that Trinity gives you the piston, sleeve, piston rings, piston pin, camshaft, and gaskets as opposed to the Wiseco kit giving you just the gaskets, piston, rings, sleeve, and pin? Is it worth it to spend the extra $800 or so on the Trinity kit? Or should I buy the Wiseco kit and get a different camshaft, unless the stock camshaft is able to handle the 440CC power? Is the 440 kit reliable? Or will I be breaking down alot more? Will I need a bigger oil cooler and oil resevior? Any help would be appreciated.:)

[Diedrich]

i dont think wiseco kits are the best..if i was you i would spend the extra money and buy a 440 kit from an engine builder ( trinity, sparks, tc, profab) getting a JE kit would also be pretty good..thats what alot of people have..their pistons are way better than wiseco

[cruzen raptor 1]

my buddy just got a 440 from thumper racing and he is very pleased with it it will even hang with my raptor on top end

[2001400ex]

Ok thanks for your help guys, I'll look at JE kits.

[cals400ex]

i am not sure what your exactly looking for, but i recommend a smaller bore than a 440. with the 440 you will need to resleeve. i also wouldn't get a high compression piston without a cam. i am actually running a 406 and i will smoke stock z's and kfx's. the only internals is a ross 10.8 piston and a stage 2 hotcam. i agree, i would probally get the je or ross pistons. the rosses are a little lighter. these smaller bores will be a little cheaper to build and they won't produce as much heat. my cam, piston, gaskets and boring cost a little under $400.00 i did the work myself since it is not that difficult with a manual.

[2001400ex]

Today I checked out the JE pistons, the biggest bore you can go to is 88mm, with the compression raised to 13.1, and the engine is bored to 426cc's if I understand their graph correctly. If I went with the JE 426 kit, will the stock cam be able to handle that amount of compression and that big of a piston? Will that amount of compression make my 400 unreliable now?

Link: http://www.jepistons.com/pdf/2002-motox11-12.pdf

[D11NR]

I have a 2000 with a 440 kit, Je High Comp piston, stock cam,
it has alot of race hours on it and its fine. But thats not saying it wont go tomorrow:eek:

[2001400ex]

Originally posted by D11NR
I have a 2000 with a 440 kit, Je High Comp piston, stock cam,
it has alot of race hours on it and its fine. But thats not saying it wont go tomorrow:eek:

That's why I was wondering on the reliability of a 440 kit on mine, do you rebuild after every season or whatever? I don't know too much about racing but I'm going to see if I can get into some local amateur races or something, that's why I want a bigger bore/more power.

[hondafox440]

There's nothing wrong with a Wiseco kit. Wiseco makes some of the best pistons and sleeves, and I fully trust (and run them) in my machines. It really isn't worth the extra $800 for the Trinity kit if all it gives you over the Wiseco kit is a cam. Cams run about $150-$300 alone - not $800.

[airheadedduner]

Originally posted by 2001400ex
That's why I was wondering on the reliability of a 440 kit on mine, do you rebuild after every season or whatever? I don't know too much about racing but I'm going to see if I can get into some local amateur races or something, that's why I want a bigger bore/more power.
My bike has had a 440 kit in it for a couple of years and just smokes a little on startup. After it is warm it is fine and I have no problems beating the shee's up the hill. I am thinking 450 piston this winter on it.

[D11NR]

Originally posted by 2001400ex
That's why I was wondering on the reliability of a 440 kit on mine, do you rebuild after every season or whatever? I don't know too much about racing but I'm going to see if I can get into some local amateur races or something, that's why I want a bigger bore/more power.


No it hasnt been rebuilt yet, I figure why mess with it when its still running strong and not giving me any problems:D

[speedy]

does any one on here no were i can send my 400 ex head to get it bored out for a 440 kit with 11:1 compresion ross piston and about how much it usually cost ??

[RED121572]

Ive got an Weisco 440. Actually its an 89mm piston, which in reality is a 435.

Any rate, Im very happy with mine. Check on EBay for these kits, there practically giving them away.

[2001400ex]

Ok guys thanks for all your info! If I do decide to go with the 440 kit will I need to adjust my valves? Should I go get the other cam if i get the 440 kit?