I have seen a 350X Three Wheeler, 85 XL350R dual sport 350, and a 86 Fourtrax 350 4X4. All the motors had two exhuast pipes, which indicates RFVC, or Radial Four Value Combustion Chamber. The motors appeared similar but are they actually different?? Of course the quad's tranny was different (auto clutch) but what about the rest of the motor?? How's the power output of an old 350X compare to a 300 or 400EX's power. Also is a 300EX motor the same as the old TRX300 motor?? And is the XR400R motor simialar to my 400EX motor??? I know the cases are different(kick/electric start) but what about tranny and crank, piston, etc?? Thanks guys!

I know somebody knows, c'mon tell me Honda boys!

Alright i'm not a rocket scientist but i think i can help ya out! About the 3 motors bein the same all i can think of is since the 350X had liquid cooling it doesnt share the same characteristics as the other to. For the XL350R i had a friend that had one of these and it is air cooled and highly strung so i'd imagine it's different from the 350 4x4. The 350X is faster then the 400EX because of the weight differences but as i recall i got my friends XL up to 75 (stock might i add) and the 350X wont do that form what i've been told. As for the old 300 motor bein the same as the 300EX's i have no clue. If you look closely at the left side behind the clutch cover there are imprints on the 400EX's case where a kick starter would be. I'd imagie that they used the same basic case mold on the 400EX as the XR400. The other differences is the EX has a biefer clutch and a slightly milder cam. Putting the XR cam into the EX really wakes it up. As for the pistion and crank as far as i know they are the same. Hope this helped ya out! Dave

Just to make a point the 350X had an oil cooler yes but they were air cooled.

from what i belive the 350x motor and the 86 350 4x4 motor is the same except for tranny and such.