I wanted to trim the windshield about 3" and couple of weeks ago I taped it off and laid out where I wanted to cut it.
fired up the ROTO-ZIP and carefully followed the line, have say it cut the plexaglass like butter and make the job very easy.
be careful as you cut, if you slip downward it will be time for a new shield.
then finish off deburring edges with a file slowly.
come out great and cant tell any difference riding but now I can see over it instead of through it..

 

another thing is to leave the tape on to protect the shield while filing or sanding the edges to prevent scratching the shield, I put one in mine when the file slipped..
I used 2" wide tape and taped about 4-5 inchs down and several layes of it.

 

Good job, I know a few other DIY'ers that did it also but that was a few years ago before the Roto's, I think they taped it off and used jig saws. I still keep mine tall on my Classic, don't like the bugs.

 

What blade did you use and any tips on how you developed the line to follow? Did you tape off the part you weren't cutting as you cut to prevent cracking? Thanks!

 

I was thinking of doing the same thing, have one of the older taller styles,
did you take pics? before and after, during??

 

You can use a band saw as well.

 

I cut mine and used this post from the DIY section as a guide. Many ways to skin a cat but this worked well for me.

 

I used a compass and set it at 2 inches and followed the orginal edge then cut it on a bandsaw. A friend of mine see me do it he used a coping saw to do his.

 

I arced the top portion of mine using a string held to the center bolt on the windshield brace about an inch higher than I wanted, then I penciled the edges in by hand. Didn't like it so I used the cut off piece and traced the factory edge for my final cut. Smoothed it out with a palm sander and then polished it with an abrasive sponge. Walla!!! Just like factory!!! +1 on keeping the tape on when sanding.

 

TOP arc
I used the standard blade and left the shield on the bike to hold it in place.
Actually I taped (masking tape) above and below the area to be cut. Its not like plexiglass and wont crack, Lexan is a lot tougher.
I make the top arc by using 12" dividers (like a big compass, metal point on both ends) using the center bolt on the cross bracket as center point of reference I taped an area right above it and put one end of the dividers to swing the arc that came close to matching the original contour then figured out how much to cut off by trail and error.

Side arc
I played with the dividers changing the swinging point around to match the original curve on the side. Then keep that radius and move it down to where it matches the line you made across the top. Again move the swing point around and make it to flow into the line just made across the top and flows smooth into the side.
Just play with line till it looks good...

I just cut it free hand and go slow and easy.

I made a cut first the top part of the shield about 1 " down (Scrap any way) just to practice and it helped to get the feel...