A while back someone mentioned Plastech plastic repair kit. www.plastech-formula.com
I just rebuilt my right mirror. I dropped the bike coming out of a parking lot @2-3 MPH. The mirror snapped off, pulling out part of the base (the triangle where the metal screws on) and splitting the stem from the base to where it flairs out to cover the mirror. The break aways never moved - I had to pry them off whit a screw driver. Anyway, I used a dremel tool, cut the four mounting studs out of the housing so I could remove the mirror capsule (so I could get access to the inside). Then I used the dremel to groove out the crack and the edges of the piece that broke out. Then sanded off the paint (the inside behind the mirror is painted). Following the Plastech directions I then mended the crack. Then reattached the piece that broke out of the housing. Then reinserted the mirror capsul and rebuilt the housing around the studs I had cut out. With care you can fill in an 1/8 inch wide slot. Took about 3 hours total. Still needs to be sanded smooth and painted. For a simple crack I'd figure an hour from start to ready to paint. Seriously, this was about as major damage as a mirror can sustain without breaking the glass - now good as new. I did this one partly to see how the stuff worked. I'm now a believer! I intend to rebuild the screw tabs on the tail sections next. Should have photos in a couple of days. If you bust your plastic, this is a viable alternative. Cost about $35 including tax & shipping for the larger size.
