i had a mid pipe laying around so chopped it in half and made a little gp looking pipe.it looks good and sounds like a raped ape,but is it bad to run it straight off the headers like that?ive seen it on alot of bikes,like gixxers and busas. will it mess up the motor? i know it affects the exhaust back pressure or something,so i dont want to leave it on there if its gonna eff up my engine.

 

I'm no expert on this by any means, but from what I've heard most of my life, that is not a good idea. Maybe some of the motorheads will chime in and be able to explain why, but I know that it is hard on your motor. Just my $.02

But on the other hand, it IS a Honda, so don't be too worried about it...

 

you don't want ANY back pressure in an ideal exhaust system. now, exhaust gas velocity and temp is what you are worried about. the worst that is probably going to happen is your bike will lose some top end HP and it will run rich which in turn will make your spark plugs not last as long. i'm currently in the process of exploring options for fabricating a *working* GP style exhaust. i'll post when i have something solid.

 

This doesn't have anything to do with backpressure, but i know running open headers on a car engine can get you good power, but you run the risk of cracking the exhaust valves as cool air can make it up the pipe and clash with the very hot valve, causing thermal cracking. With a longer exhaust you don't have this problem because it warms up any air that reaches the valves. This is why most people who run open headers put some sort of cap on them after the engine is shut off. I don't know if this applies to motorcycles, but it's worth thinking about. And yes, i've heard that you do need some amount of backpressure to avoid lean spots in bike engines.

 

the bike runs perfectly fine with it on.i just want to make sure it will have no long term nagatice affects on my bike,heres a pic.the high mount i had just wasnt loud enough
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