pipes for bigbores ??

[unclemark]

so what is everyone choking their twin pipes on the big bore's to ?? Ok here goes i put a 1100 Hooper big bore(off the 900 crank and case) into a IQr chassis and i went around and around with clutching etc.etc. and its still won't shift out all the Way ! so I'm thinking maby the pipes are choked to much ! and after the choke it makes a 90 bend to dump in the shock tower .. it was choked at 36.5 or so i opened it up to 38.5 and it liked that . so what you guys think do i need to open it up more or what else can it be

Thanks

OH i mostly ride 0-3000 ft

 

[high time]

I hope it's that simple..........

My Jaws D-pipes didn't seem to work any better than a stock single. Cold pipe my son the engineer said. I wraped them and choked them. Wow! I hit the top end so hard it broke the drive belt. After reclutching and a longer fun day, I though I had developed a mis. I had to remove the chokes the pipes were too hot. Works great now. The insulated pipe are nice in deep snow too. Uninsulated they cool off in deep snow and foul plugs.

Owen

 

[unclemark]

My Jaws D-pipes didn't seem to work any better than a stock single. Cold pipe my son the engineer said. I wraped them and choked them. Wow! I hit the top end so hard it broke the drive belt. After reclutching and a longer fun day, I though I had developed a mis. I had to remove the chokes the pipes were too hot. Works great now. The insulated pipe are nice in deep snow too. Uninsulated they cool off in deep snow and foul plugs.

Owen

Thanks !! do you remember what the pipes are choked to ? it seems like they stay purty hot on my sled all the time ! and what did u wrap them with ?

oh it dos over heat on the trail (water temp) and the pipes get really hot to wear i can drop a piece of snow and it sizzles up and evaporates !

and on the water temp i got a u cooler that 1200psi (brad) built and he runs his water craft motors with the same cooler without any over heating !

or am i looking at this the wrong Way ?? could it be something els ??

THANKS

 

[high time]

The pipes need to be hot..........

Never cool to the touch. The rebound of the exhaust pluse is what compacts and momentarally stop excess raw fuel from just flowing out of the engine. The length, size, shape, volume and tail pipe size all combine to make power. I tried 37mm chokes and removed them. I think the exits are 39mm. as they came. I could be wrong.
The pipe temps do not have much to do with piston or water temp. Wraped pipes actually keep under hood heat down and the exhaust heat goes out the tailpipe.

Owen