Anyone successfully modified the stock windshield?

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Covering the windscreen with masking tape, drawing your pattern on the tape and cutting (slowly to avoid melting) with a saber saw or jig saw works just fine. I cut mine while it was mounted on the bike, just used towels to cover everything under the screen.

 
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Anyone try this on a bandsaw? I'm mostly worried about scratching the shield while I'm cutting. Maybe just cover the whole thing with blue painter's tape draw the cut-off line and cut away. I could cover the band saw table with tape as well.

I've got just about every power tool known to man, so I'm open for options.
The bandsaw worked like a charm. I'll post some pics shortly.

 
For those who haven't done it before with home tools, the safest method to trim a windshield IMO is to use a 4" sidegrinder with a cutoff wheel, and trim with a flexible sanding disc in the same grinder.

Leave the shield on the bike. Start with multiple layers of masking in case of the unlikely event that you slip or some such. Cut wide of the mark because the wheel will leave a rough and partly melted cut line. Angle the wheel for the tighter corners. Once the offcut is removed, switch to the sanding disc, preferably the semi-rigid type (50 grit or so) that goes over a rubber backing disc. Work your way down to where you want to be a little at a time. Finish up by hand sanding with ever-finer grits. Use the cut-off piece to test your technique. If you're brave, sand to 600 grit and then wisp an oxy-acetylene flame over the edge to achieve a clear finish. Flame finishing works best on acrylic, no idea if the FJR shield is acrylic or poly.

As others have noted you can also use a sabre saw or bandsaw. But from lots of experience with shields as thin as 1/16th, I found a cutoff disc the fastest and safest. For production we used a very thin disk with a raised diamond abrasive edge. Very fast and reasonably clean with minimal heating of the kerf. But at home I'd just use a metal-cutting abrasive disc and suffer a little extra finishing time. It still only takes minutes. Fast enough that multiple times I've lopped off an inch at a time with test rides in between.

GR

 
Made a number of lexan windshields from scratch (flat stock) for my 2001 Concours. The stock Concours windshield was an abomination with a flip at the top that only aggravated the turbulence. With no adjustable shield it was important to have multiple shields as the weather changed.

I found that a variable speed saber saw with variable orbital cutting action was the real key to clean, melt free cutting of polycarbonate. I would then use a small block plane with the blade just very barely exposed to shape the plastic to exact dimensions. The advantage to the plane was that, (on all but convex curves, of which the FJR shield has none), you get perfectly smooth radiused edges with no sanding required. Hand sanding will work but you have to be careful not to scratch the flat surfaces of the shield.

Some guys will flame buff the edges with a propane torch. That takes some real artistry that I don't possess.

Connie w/ shorty summer shield (was my favorite)

edit - yeah I've got a thing for BBB bikes.

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Big Winter shield (I could almost get completely behind it, just peering over the top)

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Cut some groovy '60's style NACA ducts for back-pressure relief on the big shield.

The little aluminum scoop shape duct boxes that I attached behind the duct holess were not installed yet in the below picture.

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Whilst this question goes off on a bit of a tangent to the original topic, it's still shield related...

Over the weekend I and a handful of my mutant friends completed a really tough TwistyButt ride (mostly back to back mountain passes and the like), which turned quite wet from about 1/2 way through. This resulted in a lot of crap being deposited on my CB shield. Towards the end of the ride as things started to dry out and what looked like just dirty water stains on the shield turned out to contain fine sandy particles. I was in a hurry and it was already dark so during a gas stop I decided to quickly wipe down my shield with a wet cloth. That was a boneheaded mistake, since the sandy particles ended up putting very fine (can't feel them) scratches all over my CB shield. These are really fine, so just make the screen look a bit opaque. In the future I'll make sure to wash/hose off any such deposits or leave it alone if that facility is not available at the time.

Since the scratches are so fine I hope they can be easily buffed out, but I'm not sure of what product and technique would be the best to use.

 
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I drilled two 2 1/2 holes in the corner of the W, kinda like the cal-sci that I use most of the time. Then painted it black in the inside with the skyway spacers. Great for hot weather, great airflow and not much protection. But it hides the valentine and shields the GPS on the shelf.

 
I was sort of joking. Unless you want a completely opaque windscreen (which does look pretty cool) you won't want to use that.
I also called up CB and asked them, basically they didn't know, but told me any fine polish suitable for Plexiglass Acrylic should do the job.

 
I drilled two 2 1/2 holes in the corner of the W, kinda like the cal-sci that I use most of the time. Then painted it black in the inside with the skyway spacers. Great for hot weather, great airflow and not much protection. But it hides the valentine and shields the GPS on the shelf.
One thing to be aware of... If it hides your valentine radar detector from view, it also hides the valentine from detecting LIDAR to some extent. This may not be a big deal to you. Many folks believe that detecting LIDAR is just an early warning of the pending ticket. But some have been lucky enough to pick it up from anxious operators and slow down before they can get a good fix.

 
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