Motorcycle Repair: 81 Honda CB900 Custom exhaust, honda cb900, pressure pulses

Question
I am converting this bike into a trike which may involve lengthen the frame and exhaust pipes. The stock megaphone mufflers will stay. Can I weld a piece of tubing to extend the length of the pipes in front of the muffler by 8 to 10 inches without affecting performance?   Thanks

Answer
Mike, that will change the performance some.  Those systems are designed to create positive and negative pressure pulses at the exhaust valve to maximize the scavanging in the cylinder.  Adding the length will change the timing of the negative pulse which with effect the scavanging.  You probably won't feel the loss in the seat of your pants though.

Regards
Rich