'75 suzuki gt250...Buzzing around the block

Long story short, I picked up this bike in july and restored it to its former glory. Here is the links to a thread I had when I got it to now: http://www.mopedarmy.com/forums/discuss/18/60111/60111/
http://www.mopedarmy.com/forums/discuss/18/27391/27391/

I eventually got everything back to stock and had loads of fun with it, smoke and all. I found this pick and I instantly wanted to replicate it.



I cnc cut my own mold out of mdf board and layed 4 layers of fiberglass. After many hours of preping it I made a bracket that suported the fairing and also the gauge cluster. Earlier in the year I made custom clipons to give it the right stance. I'm now getting onto the pexiglass windshield. I also just aquired a '74 yamaha rd250 that had some extra expansion pipes. I'm going to weld on new headers on those pipes so they'll bolt onto my bike. Heres some pics of my progress so far:

Re: '75 suzuki gt250

Wow man, that bike is gorgeous already. Can't wait to see what you're gonna do with it. Got any more pics with the fairing on it?

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Heres a couple more pics. You can see where I put a lip in the fiberglass to make the windshild seam more smooth. Joe

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Song of a GUN! This has gotta be one of the best first posts on a forum I've ever seen. Awesome project man, loving the custom fairing! Keep it up, back in the day these things were the big 250 to beat and would nudge the ton on a good day.

Watching with interest - boingk

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good to see the build. Are you rocking continental tires?

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I like it!

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cool - another moped army person. I am beater there as well. I have a bravo that won't get out of it's own way with my butt on it.

Love the fairing - what are you doing for the screen?

I find lots of screenless fairings, and I never go there because of the difficulty in getting one.

j

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I'm friends with a plastics guy who has a hookup with a vacuum form machine. I've already cnc cut another mold for the windscreen. What happens is there will be a layer of felt over the mdf mold. When they get the pexiglass up to temp, right before they drop it, they take cold compressed air and blow it on the inside of the pexiglass. It forms a thin hard layer that won't stick to the felt, but the rest forms around the mold. The tire on the back is a Kenda, and the front is a chen chin, or something like that. I've had the bike upto 85mph or so, which is about top speed stock. I've found that with the clipons and laying on the tank, it increased the top speed greatly. After I'm finished with this fairing, it should add 5-7mph at least. Added to the expansion pipes, I should be able to break 100mph without breaking a sweat.

Heres the mold I made for the windshield. I've since then smoothed out the edges that you see

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I've slowly been working on it. I've found a much better way to mount the mirror. It was originally a bar end mirror, and I hated it. In the original picture, it was mounted directly on the fairing. I was able to mount the mirror through the fairing onto the bracket, making it rock solid. I also finished up the bottom mount that will secure the "tails" of the fairing. The actual paint is a dark gloss black, unlike what you see in the pic. For $10 shipped I got flush mount turnsignals that will be mounted onto the fairing. Whats cool about these is the lightbulb is pointed towards the "front" of the turnsiginal, so they are barely seen from the front view, but very bright when lit up. I'll try to get more updates done, I'm still waiting on the windshield. Joe

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I had to take a small detour from the fairing and focus on the engine. I took it completely apart because of a suspected crankshaft seal leak. Apparently it was just stitting for too long and I couldn't drain all of the gas/oil out of the crankcase. While I was in there, however, I cleaned it all up and did a few things I wasn't able to get to this past summer. I found that the cylinder transfer port didn't match up with the base very well at all, so I port matched it. I also sandblasted and polished the heads. I talked to the plastics guy and with my mold I made, there is no good way of getting a clear plastic off from it. It would take way too much work to get it to work. What I can do though is have it made out of a solid color abs plastic. I will still need to paint it but it should turn out decently. And get this, to pay for the material and his time, I get to spend a day at his shop and do some manual labor! What a great way to get my name out and do some real life work at a place where I want to start my career in. Heres a few pics to show my progress. Also, If anyone has any questions on torque settings, measurements, timing, etc, I know this engine inside and out and I should be able to help you. Thanks, Joe

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Lookin great! damn thats a clean dome!

couldnt they make a mold out of abs plastic and then make a clear mold off of that?

would be kind of dumb to have a colored shield in place of a clear screen

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Jesus...now THATS a transfer port, not to mention a cylinder head! Looking very, very good there man. This thing will run like some sort of cliche once you get it on the road!

Cheers - boingk

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fairing is baller!! howed you make the shape of it? any pics of that process?

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Beautiful stuff man! You should have your plastics guy make a fairing out of plexi. Wouldnt it be lighter than the glass? I just picked up a 72 T250. Id be interested in one of those fairings if ya feel like making another, or another mold so I could make the fairing...

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I started the fairing by spending a good month on the design. I used mastercam, a 3d cad software that my dad uses at his machine shop. Heres what it looked like on the pc:



I used 2 4'x8' sheets of 3/4" mdf to create the molds. I made it in two halfs and used a cnc machine to cut it out.



Here is the final product:





It took about 10 hours of cutting on each half, not including setup time and tool changes. I first layed 2 layers of fiberglass. It held the shape well, but it was way too flimsy to hold its own. I added two more, using larger pieces of fiberglass and it is now very firm. It was about 1 hour for each layer. After that, it was countless hours of priming and sanding to smooth out the imperfections. Von, sorry, but I think it would be way too costly to make another fairing. Even if I only lay out the fiberglass and cut it out, no sanding, finishing, etc, it would be worth about $250 of material and my time to create it. I made this fairing not as a “one off” but I do have the mold to make more in case something happens to my current one. This is what I have run into when doing custom work. Some people aren’t willing to pay me for my time. Thanks, Joe

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Gotcha...

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What I can do is give you detailed drawings and the cad file if you would like to replicate it. I can measure my bracket and what I've done and the problems I've ran into to make sure yours will go much more smoother than mine has.

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Thanks man. Im no where near that now, but I may hit you up later! Thanks again!

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Those transfers look like the need some gasket matching, steps thay big disturb flow big time.
should do about 110~115 with all the mods

PJ

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That just looks gorgous with the fairing on
Nice work with the CADing, wish i had resources like that :