After market exhaust?

Does any one sell after-market exhaust tubes, pipes, tips etc... for a 81' seca 750?...My turn-outs are creating no back pressure and the bike runs like crap...but I don't want to go back to the trumpet pipes...

Any links or customizing suggestions are appreciated...
Tyler

 

Mac make some... try making some baffles before giving up - do you have access to a good welder? I suppose for a trial you could always use JB Weld... it does stand up to high heat and it is pretty damn strong.

 

PLease elaborate...

I have a welder and my buddy builds hotrods...he is helping do all the chopping of my bike. The pipe turn-outs are pretty short though right now....do you think there is enough room?

 

if you could make a cut out circle and weld it inside the pipe - far enough in to hide them (paint them black when done I guess)

This will restrict the air flow... then just drill them to get the airflow you wanted - more holes more air...

The question I suppose would be how many holes... maybe do something like the end cap of the stock exhaust as a starting point - probably make it slightly more restrictive as the pipe is shorter... is it still a 4 into 2 into collector into 2 ?

 

Yeah, I have just unbolted the trumpet sections and put on the turn-outs...
They are not even close to air tight...I would have to weld them closed as well...

It sounds pretty simple actually...in theory..

 

then you could install the baffle in the turn out where it meets the collector... making it easier to get at (straighter pipe) and hidden from view.

air tight would help... it certainly won't help with the free flow problem

 

another interesting trick, since you got a welder (tell me thats a recent photo!) is find or make a donut steel washer that fills the diameter. drill a hole top & bottom. Run a bolt thru there, then tack the washer to the bolt. Now you can turn the washer, with the bolt, to vary the amount of back pressure, making your own "tunable" ex system.....if i aint clear, ping me & ill try to do better....

 

The '82 Maxim I picked up came with Kerker 4x1 pipe, which was in rough shape, plus blocked oil filter removal and no center stand. Had no luck finding original 4x2 (don't think Seca 4x2 will fit, but 4x1 aftermarket seems like the same for both bikes). Just bought a black MAC 4x1, which looks good, allows for oil filter room and center stand. Can definitely feel less performance than Kerker pipe had, but Kerker had a flat spot between 4000 and 6000RPM which is now fine with the MAC. Kerker might have needed jetting, while I think the MAC's are made to work without re-jetting.