My new Hybrid

[digginfool]

So they share the same bore and stroke; no advantage there.  Obviously, the only difference is in breathing and, most likely, flywheel weight.  For the added weight of a quad, I think a wider power band with more torque would be more useful than a motor tuned to move a 200 lb dirt bike.  The CRF motor can't have much more than a few HP advantage on the top end.  That's great if you're running the dunes but last I checked, we don't have too many dunes you can ride on in Florida.  All that aside, though, it is a very clean conversion.  Good job.

[xr100racer]

crf450 motor has higher compression, geared differently, etc   

think its about a 15hp difference over the trx450

[svtbolt04]

Nah, they run the same compression also. And the only thing you could keep for the gearing on the quad would be the 13t sprocket up front.. Because I believe the bikes run standard around 48 whereas a quad runs 38.

quad=12.0:1
bike=12.0:1

for some reason, I could believe the lighter flywheel theory.

[digginfool]

Actually, I did a little research and the CRF motor has about 11 HP on the TRX motor (50 vs. 39).  I also saw mentioned that the CRF motor does have higher compression.  Not that that is a good thing; remember, with the higher weight of the quad, you will be putting more load on the engine in low RPM situations which invites detonation.  Also, this goes back to the flywheel situation.  I would almost be willing to bet money the CRF motor has a lighter flywheel which would put even more load on the engine in low RPM situations.  Again, though, it is a very clean conversion and I'll bet money it is WAAAAYYYY more satisfying to ride than the stock (or even modified) 400EX was.  I'd take it for a spin!   

[The hyrbid kid]

Its awsome the gearing is great i have a 14t ont he front and a 36 on the back..
I also have a 13.5.1 piston..
Im having stainless valves put in it now..
I dont really like they way the trx's feel i have one but done hardly ride it..
The 400ex feels alot better and handles great.
I love the combo its a blast to ride..

[1FasterBlaster]

I was lookin for ya at Croom Sunday.Did you go?

[The hyrbid kid]

No my freind made a track on his job site down in vinice so i went there and rode..
I wanted to go to croom bad but glad i didnt go because my bike took a poop..
Got the vales being set right now ill have the motor back thursday tomorrow and ill be ready..
I might go to hardrock saturday with trx#9 and a freind..
But i got another hyrbid on the way.. i pick it up monday..

[trx#9]

No my freind made a track on his job site down in vinice so i went there and rode..
I wanted to go to croom bad but glad i didnt go because my bike took a poop..
Got the vales being set right now ill have the motor back thursday tomorrow and ill be ready..
I might go to hardrock saturday with trx#9 and a freind..
But i got another hyrbid on the way.. i pick it up monday..