BSA B50 -500 APG Build

Started by Koncretekid, February 26, 2011, 04:19:48 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Koncretekid

The windshield finally arrived after a 6 week wait.  But it is a too short at the triple clamps and at the head area!  It came in Thursday PM and by evening, Doug had it figured out.  Thursday evening, Doug made a 2 layer band of fiberglass and resin by wrapping wax paper around the fairing, to get a 4 " wide flange with the approximate shape. The first photo shows the windshield propped up in place by using wooden blocks glued to the fairing. The 2nd photo shows a piece of the pre-formed band glued in behind the windshield.  The 3rd photo must have got dust on the lens, but shows the pre-formed band glued in place ready to be reinforced.  By Friday evening, Doug had the flange properly glassed in place ready for trial fitting. The 4th photo shows the windshield at its proper loacation on the flange, ready for the filler piece to be made.  To do this, Doug will remove the windshield, and use a band of plastic against which he will glass in the space to match.  I am leaving for Colorado Monday until end of May, so I won't be able to do the final fitting until then. 

I also have to make a new exhaust pipe with an exit thru the side cover.  Can anybody tell me the best way to make an exit thru fiberglass that will not get too hot?

I'm concerned about cooling, as the only cooling air I have allowed for is thru the fork tube openings, and an additional 2" diameter inlet on the front edge of the fairing adjacent to the front wheel.  I have another 2" opening on the other side of the fairing, but I wanted to duct this air back to my carburetor.  Any ideas out there on this?

Tom
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

Koncretekid

Two more  photos.
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

55chevr

I used aluminum rolled and fiberglassed into the seat with about an inch of clearance all around the pipe  .... didnt show any heat ... Joe

55chevr



You can see the pipe exit in the tail piece.  Thought I had a better photo

55chevr

A little better view

Old Scrambler

The Beezer is looking really FAST!.............Do you have the largest tranny sprocket and smaller rear sprockets?  It looks to me as though the air will be pushed away from the intake 'holes' by the flair of the fender over the forks when you get over 100 mph.  What about adding a small slot just below the 'front' of the fairing for more air to the head? 
2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2018 AMA Record - 750cc M-CG HONDA CB750 sohc - 136.6 mph
2018 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 143.005 mph
2018 AMA Record - 750cc M-CF HONDA CB750 sohc - 139.85 mph
2018 AMA Record - 750cc MPS-CF HONDA CB750 sohc - 144.2025 mph

Chassis Builder / Tuner: Dave Murre

wobblywalrus

The goal with the scoop shape is to keep the fuel, intake air, and cylinder head cool.  The bottom is more open than I like.  Clearance for the fender when the forks are compressed is why it is open.  Your bike does not have this problem. 

panic

JM2ยข?

Remember the Kawasaki H1? The front fender was part of the cooling system - remove it, and the center cylinder overheats.

The JP Norton team discovered that the fairing pushes a "plug" of relatively still air ahead of it, partially enclosing (and streamlining) the front wheel. The engine's air intake had to be relocated.

Haven't read the rules, but if the speed is high enough a fairly small tube ending in a slight flair can protrude from the W/S area forward enough to get clean air for the carb.

Conclusion: you won't know until you try it at speed.

JimL

If you're exiting the pipe low on the side, just use an elbow.  Look at the build diary for MPS-PG-500 bike.  That was the Dan Wagner Honda.  I put heat tags along my pipes, one year, and found the end of the pipes did not color my 200 degree tags...even 10 inches from the outlet.  We use short shallow angle mega, so the heat is spread pretty thin by the end of the pipe.  We did discolor the fairing at a head pipe bend due to firm contact with just heat wrap.

I use a piece of diesel exhaust elbow on the end of the Meg.  Hope this helps.
JimL

wobblywalrus

That windshield looks good.  Did they use the bubble method?  What kind of plastic is it?

Koncretekid

#250
Dennis, and confirmed by Panic, a small opening just below the windshield, and maybe extended outward, may be the best place for bringing in air.  I'll explore all the possibilities.

Joe and Jim, Good advice on the exhaust.  I went back to your MPS 500 PG build, Jim, but did not see the exhaust you were talking about.  I assume also that the 126mph record still stands.  I, of course, am in the APS 500 PG class, but that will be a goal to beat! Is Dan going to give it another try?

Dennis, here is a site I stumbled across that should be right down your alley.  Have you met these guys?  Their fairing looks to be the exact one I started with - - from Airtech for the CanAm 125. http://www.smokeandthrottle.com/2011/01/supercharged-triumph-tiger-cub-goes-for.html

Jim, I'm off to Colorado today and will be there in 4 days until May 25th.  Will you be in the area then?

And, Bo, the windshield was custom made by Gustafsson. I don't know if they blow or vacuum it. It is cel-cast acrylic.  They do not make them out of polycarbonate.  My welder friend, Steve Gray, certified aircraft mechanic and re-builder, said that cel-cast acrylic is the only material allowed on small aircraft, so it should be sufficient for a bike windshield.

Tom
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

Old Scrambler

Thanks for watching out for me...............I have been all over that Tiger Cub build from the beginning............They run in SCTA with somewhat different rules. We are getting excited for this year with a second motor build but still a few cc's short of the 250 max.

Enjoy your time in Colorado!
2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2018 AMA Record - 750cc M-CG HONDA CB750 sohc - 136.6 mph
2018 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 143.005 mph
2018 AMA Record - 750cc M-CF HONDA CB750 sohc - 139.85 mph
2018 AMA Record - 750cc MPS-CF HONDA CB750 sohc - 144.2025 mph

Chassis Builder / Tuner: Dave Murre

JimL

#252
You can see the end of the exhaust if you look at pic of bike in impound. Also, go to http://home.earthlink.net/~leinfam/index.html (Jim & Jeanne's Site) and look at pics on third page to see the bike with fairing.

The record youre after is mine, set with pretty stock CX500 engine.  That bike only ever made two passes, shutting down at the 2 mile so I could get out of the way, i didnt expect it to go as well as it did (126 on the second pass and still pulling, but i only had 2 days and back to work.)  I hope you do well and get it out of there.  It's lower than Dans record set with a shaft drive!  Dan and I are done with the shaft drives.

I'll might catch you as I will pass thru in April on our way to pedal the Slickrock trail at Moab.  Hope to see you at speed week.  We still have work to do on Dans MPS PG 650 bike, but my APS PG 650 bike is ready to go.

Drive safe and best wishes for you success!
JimL

55chevr

No one owns a record ... they are just on loan until the next guy breaks it ...

JimL

Exactly right! ....and some need a new borrower as soon as possible, like the one we're speakin' of.  :|