Join Date: May 2012
Location: Toronto, Ontario.
I've added a four holes to the base of my Givi windscreen. It reduced the turbulence somewhat but noise levels seemed the same (earplugs only in my case).
Start with a 1/4" spade bit to place the holes. Space them to allow for enlargement if needed. Before you break through, put the drill in reverse and push--this will melt though the last bit and reduce potential cracking. If you're drilling the windscreen while it's on the scoot, put a barrier behind it, so the drill point doesn't prick the dash housing.
Air does flow through even at 1/4" diameter holes, but not much (enough to blow plastic shavings out). I increased the holes to 3/8", then (after a test ride) to 1/2". As I mentioned previously, it seemed to help a bit.
Given all the curves and protrusions, I doubt the Big Burg is very aerodynamic and the rider/equipment variables complicate matters further.
Edit: I also cut the screen down by 4", since I dislike looking through windscreens on motorcycles--once they pickup bugs/mist (especially commuting in the rain), they get difficult to see through. It also reduced the quite strong buffeting at helmet level.
Last edited by Flywheel; 08-13-2013 at 10:30 PM.