Search Messages

 
Author:
Search Start Date:
Search End Date:
Sort Order
Sources to include:
OR Message ID:
 

Display Mesage #100718


DIY Windscreen extension - Part 1
Written by jim.strtr on 2/14/2011 at 04:53 am

Acrylic cracks but Poly-carbonate does not. Poly-carb is used as rivets in the
plastic industry, but it scratches much easier than acrylic. The best is a
coated scratch resistant poly-carb, but it is hard to find. Good luck, let's
see some pictures! J.S.


--- In ipcrc@yahoogroups.com, "dl_page" <dl_page@...> wrote:
>
> My PC800 has a stock windshield, and driving around at speed can be a major
PITA without earplugs (or hunkering down over the handlebars like a pizza
delivery scooter driver to get out of the draft).
>
> After a quick search on the interwebs, I came across a kiwi who, on a BMW GS,
added the visor of an old skid lid with duct tape.
>
> <eureka moment>
>
> I had an old crash hat hanging around that has been used and abused and I have
been thinking for months how to retire it (without anyone going through the bins
as it happens and getting resold on a yard sale), and so it's been sitting in
the basement. I removed the visor, and with the help of some duct tape, taped
the visor, upside down, to the top of the PC windshield: The DLPage Extension
Prototype MkI was born (yesterday evening).
>
> Results: Not earth shattering, but I could comfortably ride with a flip up
helmet in the up position without getting the wind in my face and the wind noise
I would get at 50 came at 60. And it did not disfigure the bike. I needed a
bigger version.
>
> This morning, I grabbed 2 sheets of acrylic from my local
open-on-sunday-builder-and-DIY and supply shop - 500x250 mm sheet, 2 mm thick,
2,50 euros each (2 bucks?)
>
> Using the old visor as a model, I redrew a shape but extended the base by 60
mm, cut it out, and then tried to thermoform it (too hot, screwed it up, had to
heat with a hot air gun to flatten it).
>
> Anyway, being a prototype, I was not too hacked off, so I went and placed that
on the bike, attached again with duct tape. Extension Prototype MkII.
>
> Result: Noticibly less buffeting and wind noise. What I got at 60kph with the
MkI came in at 80-85 kph now (but optically buggered by my thermoforming
attempt), i.e. distorted and warped to heck even if I did more or less flatten
it out again.
>
> With night falling, scientifically mesuring the windscreen (with lengths of
duct tape (the "Dl" in my name currently stands for "Bubba") and using the MkII
as a guide, I build the Prototype MkIII.
>
> Cut and basically shaped, not thermoformed, and another 5 inches higher than
the MkII. On taping to the windscreen for tests, when bending it, a crack was
heared and a minute cloud of stars appeared in the dead center of the screen
(less than 10 mm across), so any further attempts must be thermoformed into a
curve as to relieve stresses in the plastic.
>
> Taped this to the windscreen and took it for a ride.
>
> Oh. Wow.
>
> 90 kph and I can still hear the engine without hunkering down. No more severe
buffetting (unless you peer around the windshield sideways), no more severe wind
noise in the hat, but now a distinct whistling can be heard that starts at
110kph.
>
> I got the bike up to 130 kph (80 mph), and it was great - actually scary as
not having the wind noise giving you feedback about your current speed and
driving in the dark, you go into bends too fast (thank god I changed the front
anchors 10 days ago!). It does not look too bad on the bike either.
>
> A photo of the extension, in my living room, with a glove (size L) for scale :
http://www.danielpage.com/images/windscreen_extension/proto_mkIII.jpg
>
> I need to make a MkIV to a better design : It needs to be curved and shaped (I
am going to make a shaping jig tomorrow and get another sheet of acrylic). It
needs to be sized better too, to fit in with the stock windscreen. I'm still not
sure how to attach permanantly: Some sort of clipping arrangement or just sink
3-4 holes and nylon bolts with wingnuts for easy removal?
>
> The MkII and III prototypes will probably be cut in half up and recycled as
feet wind deflectors...
>

Message Thread for message #100718