Snowmobile Saw help

[titanium]

I was planning on building a saw from a 3 cyl rotax snowmobile.This is just a hobby project and it won't be raced.I have all the snowmobile parts at a reasonable price,and have been racing modified snowmobiles for many years.My question is how to attach the drive sprocket to the crank.On a sled the ignition and flywheel is on the same side as the chain bar for the saw.Do you reverse the crank and put the ignition on the other side?All the pictures I have seen of hot saws look like the chain is running real close to the side of the cylinder.If you would bolt the sprocket to the flywheel it would be offset by about 2 inches.Any help would be much appreciated.

 

[ironman_gq]

most guys use a bike with the tranny cut off so you can get close with the sprocket but your in a different situation so Im not sure what to suggest

 

[troutfisher]

My saws are Dirt Bike/ATV motors, I've never built a sled saw. Do a Google Image search for "hotsaw", you'll find lots of pics. This looks like a rotax motor, I see the black power valve in the front. Is that the ignition trigger on the left side of the crank? You'll probably recognise snowmobile parts that I wouldn't.............

 

[Nitroman]

I think a Mach Z motor is going to require you to be built like Hulk Hogan or similarly. If it weighs as much as my XCR-800 motors, and without pipes too.

I do know on the Polaris 800 motor, the mounts (screw holes), for the ignition stator are on the MAG side of the motor, and the casting is slightly different on that side too, so putting the sprocket on the PTO side would be infinitely easier. I don't know the set-up on a Bombardier.

 

[titanium]

Thanks for the photo I can't really tell what it is though.I thought because lots of guys use rotax hot saws a sled engine would be good to use.I think a bike engine would probably be easier though.

 

[ironman_gq]

I think Ive seen em cut in half and only half the engine used

 

[titanium]

Nitroman,the rotax is setup the same as a Polaris,I was thinking of turning the crank around and redoing the case so the mag and pto would be opposite of a sled.

 

[titanium]

I guess I should have said that I'm only using one cylinder out of the 3 to make the saw engine.

 

[troutfisher]

I think the sled builds are harder, but there's more displacement to be had. 300-400cc's is common. Half of a 600 Rotax twin, half of a 800 arctic cat twin, ect. I have a Yamaha 500 twin here, I just haven't come up with a plan yet. That would make a 250 single, but I'll bet that a 250 motocross bike will make a lot more power. I just happen to have a RM250 here too.

 

[Chopwood]

Boy I wish Cahoon was still here. Haaahahahahahaaaaa!

 

[jropo]

I guess I should have said that I'm only using one cylinder out of the 3 to make the saw engine.

I have an old artic cat single,250 I think.
I was thinking the same.
I cant find a small bike motor that I can afford.

 

[ironman_gq]

Those old arctic cat singles were only like 20hp while a modern engine is closer to45-50hp stock