Question about YZ426 engine

[400MXer]

is it possible to put the yz450 cam with the automatic decompression in the yz426? so i could get rid of the decompression lever and make it easier to start.

there are some good deals on aftermarket framed yz426's, but i've heard that they are hell to start! What is all of your thoughts on this motor?

[mxracer111]

my ride is a yz400 in an ex chassis..... it isnt bad at all to start.... when you KNOW HOW to start it.... thats all it takes..... you cant just go kicking the hell out of it.... and as long as you have a hotstart button like most do your fine..... but to answer your question

you can put in the yz450 dirtbike exhaust cam! also you plug the hole in the head with a plug from the yz as well..... the lift on the yzf cam is BIG.....so some engine builders will recomend going with stronger titanium valves if you dont have them already....but i have talked to many people that run that cam with stock valves..... i will be doing this conversion over the winter in my motor! it deoesnt make it much easier to start....just takes the decompression lever out of the process..... 1 less steo to start....and it will kick over easier....

[Math]

mxracer111, what modification were require to put a 426 engine in a stock 400ex frame? I know for the radiator.

[mxracer111]

check out my websie..... www.woodwardspecialties.com...... make your way to pics of custom quads.... i havent put up the finished pics yet.....

but anyway.... motor mounts.... headstay etc.... rad. mounts.... make an oil tank.... pivot bolt spacer. mod the subframe to make airboot fit nice....there is all kinds of crap to do..... personally ...i dont think its worth it with the yfz being out..... but mine was done before ..... plus i have all aftermarket suspension sitting here for the 400ex chassis when i started....

[mxracer111]

o yeah....and the big downfall to it all.....

after you ride some and break some parts.... most everything for it has to be made..... or modified... you cant jus tovernight new parts in to fix it ...that is what i hate about it.... i love the quad....but when it comes to repairs and all....it takes time. and i dont like to be down any