Do you recommend the exhaust baffle in or baffle out?

We typically prefer the baffle in on stock motors and baffle out on built motors, but it's really up to you in all but extreme cases. Try it both ways at the track, and see which way helps you go faster. Many people like it out at the drag strip so they can hear their own bike/shift points -- over the bike in the other lane. It's easier to anticipate your shift points by sound before you look up to view your shift light or tach, etc. 

Special Note: Some people believe that having the baffle in is REQUIRED with a stock engine, especially with a sidewinder. This is not the case with our patented TiWinder and our 4-2-1 sidewinder exhaust systems, although many of our competitors 4 into 1 systems have seen advantages from what we understand. All Brock's Performance under fairing exhausts and sidewinders are 4-2-1 construction, so baffle use is really a rider/social preference.

Special Note to modified engine users: In high horsepower applications (above 230 RWHP) and/or when using nitrous oxide, measurable gains can be noticed when removing the baffle if using our 4-2-1 Sidewinder or ShortMeg (above 200 RWHP). When using our patented TiWinder with the race baffle installed, minimal power losses (less than 1%) may be noticed on the dyno even at horsepower levels approaching 280 RWHP normally aspirated. But substantial increases in speed have been recorded at the drag strip and in land speed testing as a result of reduced high-speed exhaust 'resonance' (a phenomenon noticed at speeds above 180 MPH and most prevalent in high altitude racing, which is cured by the addition of a fiber-packed/high flow baffle.)