When Al Baker commercialized his Baja Commander kit for the XR500, he included a nice purpose-built exhaust header that had two particularities to deliver more power:
- bigger bore for better breathing out (ID: 29mm I believe),
- identical lengths for both bends, allegedly helping the harmonics of gas flow.
It was also a clear visual statement that the bike had been tricked.
It took me no less than 4 years to finally find one of these original headers. It came, as often, in the form of an eBay miracle, for a handful of dollars.
It looked a little gritty at first.
It ended up looking perfect after derusting and high temperature paint.
Al Baker also made a Mugen muffler. I was lucky to find one too!
Had to fit a spark arrestor to ride in California.