wolfy77
XS650 Member
Are 1 3/4" pipes too big for a stock 650? Even with Omar's Exhaust Optimizer and port inserts? I'm looking at his claimed power gains and they are enticing.
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Schmidty
XS650 Member
Everything I've read about the 1-3/4" pipes has been positive. Better flow means more horse power, the same reasons people put larger diameter pipes on their race cars.
I've also heard Omar's optimizer works really well.
I've also heard Omar's optimizer works really well.
wolfy77
XS650 Member
Ya I'm just talking to Omar right now actually and he's giving me the thumbs up for stock motors. Waiting to hear if he is going to fab up some Hooligan pipes or if it's just the Mile High and Half Mile.
Thanks Schmidty.
Thanks Schmidty.
wolfy77
XS650 Member
Ya I'm just talking to Omar right now actually and he's giving me the thumbs up for stock motors. Waiting to hear if he is going to fab up some Hooligan pipes or if it's just the Mile High and Half Mile.
Thanks Schmidty.
Thanks Schmidty.
650performance
XS650 Addict
Yes, they are too big. Generally speaking, for a stock 650 use 1 1/2" i.d. pipes. For a 700 you can use 1 5/8" i.d. tubing. And, for a 750 1 3/4" is the ticket. But, like anything, it's more complex than these basic sizes. For example, a XS engine with a basic Shell setup (750, 10.5 - 1 c.r., 38mm VM carbs, Shell #1 cam, some head work) is very happy with 1 3/4" pipes, but on the street where mid-range becomes more important, 1 5/8" pipes gives it more usable power from idle all the way up to 6000 rpm, at which point the larger pipes begin to gradually assert their superiority.
650performance.com has a link with a ton of information about exhaust pipes for heated up and race XS engines. Scroll down on the landing page to find the link. (For some reason I can't get it to appear here on this post, so you'll have to get it.)
I really like how TT pipes feel on the street, both with stock and modified engines. Tube length can be anywhere from 29" - 42" (measured along the tube's centerline from EX valve seat to pipe end) depending upon the engine's state of tune. The easiest thing is to begin with pipes that are about 45" long, ride it and then begin cutting a few inches off between rides. When you figure out the "right" length then - if necessary - weld on on appropriate length extension to obtain the desired dimension.
650performance.com has a link with a ton of information about exhaust pipes for heated up and race XS engines. Scroll down on the landing page to find the link. (For some reason I can't get it to appear here on this post, so you'll have to get it.)
I really like how TT pipes feel on the street, both with stock and modified engines. Tube length can be anywhere from 29" - 42" (measured along the tube's centerline from EX valve seat to pipe end) depending upon the engine's state of tune. The easiest thing is to begin with pipes that are about 45" long, ride it and then begin cutting a few inches off between rides. When you figure out the "right" length then - if necessary - weld on on appropriate length extension to obtain the desired dimension.
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