new EX motor vs yz400 motor

[Juggalo]

ok guys i need some advice quick. i will have around 1200 bucks to spend right now. i am putting a new motor in my quad but i am kinda torn between these 2. i could buy a 400ex motor with a high compression piston for 850, then i would put a cam in it, throw it in the quad and ride. or i just found a sweet deal on a yz400 motor for 800 bucks. it comes with electrical and stuff but i dont know about a carb (if it doesnt come with a carb i will prob pass). if i bought that for 800 bucks i would still need to buy an engine mount kit, radiator, exhaust, ect and spend a lot of cash. i'm wondering if its worth it going with the yz400 motor over the ex. and i dont know how much this stuff costs either. anybody know the price of a radiator, motor mounts, and what i can expect to pay to get this motor operational in my 400ex frame?

[Chanman420q]

id say if your a metal professionalist, go for modding the 400 frame for the yz400 motor. yes it will cost more, but it will sell for more and make a ton more power. OutlawEX had a 406EX that was built by PR racing. i believe it was a national kit and he said the stock YZ engine would just run complete circles around his ex engine.

id say go for the YZ if you dont mine a project, ur good with metal and have the funds available. If not, just buy the EX engine, ull be back on the track in no time

[RiPPiNiTuP7]

the yz motor is a monster compared to an ex engine. ya sure it will cost more to build the yz, but in the long run its worth the extra time and money.

[K_Fulk]

Your gonna have to spend atleast another 1000 to get it running. Pipe, radiator, kickstart, extension, custom oil tank, and getting your frame converted an repowdercoated if you cant do it your self.

And if you ride at night any how are you gonna hook up lights? I dont think there is any provisions for them on the yzf.

And you can still find a pretty bad ex motor for that kind of money. I just bought a full tc motor for 1400 and it runs pretty damn strong. May not be yzf strong but its a lot less hassle putting in a stock motor than converting to a new motor.

I really dont see the point in building ahybrid anymore with the production quads out there and ready to go.

[Florida400EX]

I'd stick with the EX engine, cause the YZ400 engines are like 6 years old now, and will start becoming unreliable. When all is said and done with the cost of the motor you will be at around 2k.

[s-10s_rule]

On the GT Thunder website there was a dyno run comparing a built out the arse 440EX motor and a stock or very close to stock YZF400 motor each on their respective frames and they were almost identical in power curves, with the YZF400 overcoming the EX in the upper RPMs. It was quite interesting, I think it might still be on there, "just goes to show it takes megabucks to get the same power out of a EX motor as a stock YFZ" (the caption was something like that I believe) It would be a tough choice, you'd have alot more headaches trying to put the YFZ motor on there, it would be cool though... I'm in the process of putting a CBR500 motor on a Warrior frame, its on there but I need alot of rolling parts for the Warrior frame. Does anyone have some Warrior parts like the shocks, hubs, axle, and axle carrier for cheap?

[Florida400EX]

on east coasts ATV's site, it says it costs them like $800 to fit the YZ426, or the CRF450 engine into the 400ex/ 250R frame. Just keep in mind all the hidden costs that will pop up (radiator, Lines etc....)

[04'400ex'er]

If you are mechanically handy, and don't mind the extra money, I'd do the yfz. That would be something not many people have.And would be powerful.

[Juggalo]

i think i am gonna go with the ex motor. i know i could get the yz motor workin but i just dont have the extra money. plus i wanna be riding as soon as i can i dont wanna wait anymore (its been since last fall since my quad was workin)

[Florida400EX]

Good Choice, and good luck getting it running again!

[lt2504stroke]

I would stick with the reliable bullet proof ex motor.
There easy to understand and there not complete garbage you can get them somewhere. That is what I think .You can ride it sooner and not have to do all the work for the yz motor.