440, hybrid, or YFZ/R

[yamablaster24]

Ok guys im running on 397cc. I need to know what you think i should do. Get my motor bored out to a 440/stroked to 450, Or put a hybrid motor in it, or.....sell it and buy a 450r/YFZ.

The reason im asking is because all i race is 450's. Im gonna be racing nationals next year in 4-stroke B class and i need a motor to haul me. What do you guys think i should do, money is kind of short at 15.

[EvilJester400EX]

Conversion. Cheaper and the same power as a YFZ.

[brian250racer]

Just saw the other day that 'Hot Rods' makes a stroker crank for the 400ex. (June 05, Dirt Wheels, Pg133). 460cc stroker crank for $389.50. Don't know anything about them yet, so,.....??

[bakeen]

With all that stuff you got in your sig you already got a bike that suspension wise is better than any stock YZF or 450R, all you need is some power in the engine. I'd get a quality bore job done with all the extras. It wouldn't be worth it to sell what you have and get a new 450R or YZF with all the money you got already invested.

[ss440ex]

Originally posted by EvilJester400EX
Conversion. Cheaper and the same power as a YFZ.
Go with the yz 426,
MORE power then the yfz!!!
With a pipe and the cam mod.:D

[j0nhonda400]

I hear the 426 is hard to start when its hot:ermm: I would do the crf450. Im kinda in the same boat im thinking of doing a crf hybrid or a fully worked 426 big bore. I don't know yet. Im kinda worried how the hybrid would come out. im thinking about just buying another frame to chop up for the crf then keep this frame just in case.

[sampleez]

just about all the bike motors are harder to start hot. you could find a yz 426 for a lot less than a crf motor. i wouldn't even consider keeping the ex motor if your gonna run the nat's. they just can't put out the kind of power the bike motors do.

[ss440ex]

On the hot starts,
I have three of them that will restart on the 2nd kick.
The 450 decomp cam helps alot!

[blakefoote]

I would go with the 450r or YFZ. because if you ever wanted to race a production class you would be able to and they are all around good bikes for the MX racing circuit. I would go with a production bike.