Zook wrote on 03/14/19 at 17:43:28:It is a Harley Dyna muffler and The pipe is wrapped
Not a fan of wrap, It holds in heat, probably not good for air cooled engines.
One of the paths for heat loss is the pipe, The hottest part of the bike is the exhaust valve, heat reflecting back will just keep it hotter.
There might be some slight benefit in racing but racing is not about stop and go traffic and long life of a motor.
And besides some wraps absorb moisture.
Example, take some semi dry towels balled up out of a dryer and place them on a table leave them for hours. Later they will be still hot and wet in side the ball. Thus same effect with pipe wrap. Rotted out pipes.