Pimp My Exhaust

Originally posted to El Cantar de la Lluvia on Saturday, July 15, 2006




No, worry not. I didn't buy one of those fancy exhaust pipes. It was just something I was curious about, and I ended up doing it out of boredom and without expecting any power gain whatsoever.



Here's the deal: when the exhaust header is welded together, the process leaves a raised lump all the way around the inside of the mouth of the pipe. In theory this reduces the diameter at this point, and reduces the power output of the engine. I personally believe that this is truly a tiny contribution to the total losses that the engine's power is subjected to.








The idea is to grind it down. I already had the exhaust manifold off the bike, so I decided to clean it with Peek.

The whole process probably took an hour and a half of grinding away with the drill, removing material from this rased bump at a glacial speed. Since I had everything off the bike, I took a pic looking into the exhaust ports.

A few days later I checked the oil level (a tedious process on the XR) and took a look at the spark plug.







And that's about it.