Torque motor? How would you do it?

[Derrick Adams]

Just throwing this out for conversation.

If you were going to build a stock jug motor for all low-end, how would you do it? Port timing, flywheel weight, pipe, reeds, carb?

[CorvetteZ06]

for a stock jug/head, i would go with low end porting, a trx 7 pipe, cr-head gasket, 35mm A/S, and a pyramid reed valve.

[jhtrx250r]

That last post looks pretty good, I built one like that for a friend,
I did a 86 short rod motor, 86 cr style piston, 89 stock un ported cylinder(the 88-89 cylinder stock porting is great for low end )
CR head gasket, 35 A/S carb, FMF fatty pipe, boyson rad valve with reed spacer, It was, and still is a torque machine and any one could ride it, it is super reliable.

[86 Quad R]

Originally posted by jhtrx250r
That last post looks pretty good, I built one like that for a friend,
I did a 86 short rod motor, 86 cr style piston, 89 stock un ported cylinder(the 88-89 cylinder stock porting is great for low end )
CR head gasket, 35 A/S carb, FMF fatty pipe, boyson rad valve with reed spacer, It was, and still is a torque machine and any one could ride it, it is super reliable.

i built one just like that but the only thing i did different was i used the long rod crank. it will comfortably carry a 6'3" 300 pounder. :D

[Honda 250r 001]

wouldnt a stroker help ya out with torque. a torque motor doesnt have to be low end either.

[Honda 250r 001]

bump. anyone got any more ideas?

[kyledvor61]

4 stroke

[JM317]

Originally posted by kyledvor61
4 stroke
cough, cough, 400ex. JK

I'd probably go with a long rod crank and smaller A/S carb too. I used a 12t front sprocket before and even though it's hard on a chain IMO, it makes a difference on the lowend pull.

[Derrick Adams]

Well, we ended up building a pretty strong torque motor. We used a +4 crank and 310 Pro-X cylinder with lowered port timing. Makes tons of power and pulls strong all the way. Right now we're running a 38mm carb and an ESR low-end pipe.

It's an absolute animal!

[jcs003]

the right pipe choice is key. i went from an FMF fatty to an ESR trx6 and it was a huge improvement. put the power just where i needed it. i also rebuilt my carb which helped. just a stock carb. 35 flatslide i think...

[Honda 250r 001]

how would you do a top end torque machine?

[Motofool250r]

put a 500cc jug on it and add turbo and n2o and you have a high torque high rpm mahcine

[jcs003]

Originally posted by Motofool250r
put a 500cc jug on it and add turbo and n2o and you have a high torque high rpm mahcine

that sound like one fast gernade.lol

[regg187]

Originally posted by Motofool250r
put a 500cc jug on it and add turbo and n2o and you have a high torque high rpm mahcine

twin turbo with a 2 into 1 manifold and alcohol,,,,,,,,,,, for the rider and the bike!!

[fulltiltrider]

If your talking stock stroke, I'd mill .040 off the base of the jug, lowering the port timing. Then widen the exhaust port. Fill in the hooks on the rear transfers with epoxy, Cut the transfer tunnels in an arch shape as much as you can without going through the other side lol, then epoxy the inside of the tunnel to match the shape, set squish up at .035, 35mm a/s carb with a pt type 6 or a ct midrange pipe. JMO

[Honda 250r 001]

fill in the ports on each side of the big intake port? what does that do?

[woodsracer144]

i dont know much about what size will give you power and all that but wont like a 38 AS = more gas+more air+ more power? or am i like totally off...

[fulltiltrider]

Originally posted by Honda 250r 001
fill in the ports on each side of the big intake port? what does that do?

If you look at the rear transfer ports there is a "hook" right where the charge leaves the port on the sides closest to the boost port. This shoots the charge out towards the exhaust port. You fill in the hooks so the charges hit each other and sit in the center of the cylinder. This doesnt really increase hp but definately gives you much better responce in a motor made for low end