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Discussion Starter · #1 ·
I worked on a person's 1954 Simplex Servi-cycle a few years ago and have never really gotten it out of my mind. Now that someone has uncovered and released some old Boardtrack Racing video I've been looking at them alot. I like the simplicity and style of the old bikes and decided that I want to build one for myself.

I have and old Yamaha that I want to use the forks, steering head, and rear wheel from. I want to build a dual tube frame similar to the turn of the century bikes with the long, narrow, flat sided tank, the downward bent U-shaped bars, and rigid rear suspension but with working forks and front/rear brakes. I plan on using a torque converter clutch and jack shaft similar to the Simplex automatic borrowed from a gas powered golf cart or a snow mobile with final chain drive.

Now the engine choice is where things really get interesting. I originally thought of a 340cc snow mobile engine, but a side by side twin doesn't fit the look I want. I thought of a single cylinder two stroke or four stroke. It's better, but still not the look I'm after. Since I plan on only riding this creation around town and occasionally on the highway just to help get around town I don't need a ton of HP. I'm now looking at the Vanguard V-twin made by, gasp, Briggs and Stratton. My only concern is if the Briggs turns enough RPM's at 3800 to fully operate the Torque converter. I know I can change to springs but that gives me a pretty narrow band of operating room. I know the engine is capable of powering a motorcycle because Orange County Choppers used one to power one of their bikes but their's had a 5-speed transmission.

I brought in a professional welder who is also a motorcycle enthusiast and a tool and die maker who has built and ridden his own drag bikes for 15 years to help me with the project. We will get together soon and start the bench racing and design stage to map out a plan of attack.

Most of my friends and family, except for those two listed above, seem to think I'm a fool for building and/or riding a home-made cycle. What are your thoughts? Am I crazy or just being creative?
 

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Vintage bike addict
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4,812 Posts
Build it! I've been wanting to build a bike too. Just no extra parts yet to get started. Not too sure how well the engine choice will work out. Unless you change carburetors. Throttle response would be pretty slow.
 

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Discussion Starter · #3 ·
Build it! I've been wanting to build a bike too. Just no extra parts yet to get started. Not too sure how well the engine choice will work out. Unless you change carburetors. Throttle response would be pretty slow.
Between Raymond, the tool and die maker, and myself we have quite a few parts. I've worked as a small engine mechanic on several occassions to pay the bills or supplement my income and Raymond is an unbelievable fabricator. Add in Scott to hold it all together and we have a pretty solid combination of skills to work with.
 

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Vintage bike addict
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4,812 Posts
Take and post pictures from start to finish. In my case poverty has taught me a lot of those skills. Never could afford to pay others to fix things so if I wanted it working I fixed it myself.
 

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I say go for it! Course people consider me nuts anyway! *:shock: imagine that!*:lol: :lol:
I'm not really nuts just a bit :twisted: is all! :lol: :lol:
 

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Vintage bike addict
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Okay we're waiting for in progress info. Sounds like a great project. Have you guys gotten started yet?
 

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Go for it. I've built a bunch of bikes from the ground up and the feeling you get when you take the completed project out on it's first ride is hard to describe - not to mention the difficulty you have in getting rid of the smile on your face.
 

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Discussion Starter · #11 ·
Right now we are assembling the parts and tools well need to do the project. We've got the tubing bender, tubing notcher, tubing, plasma cutter, welder, and the parts bike. I've got to get with a friend of my dad who has a lot of scrapped golf carts and find a suitable torque converter and jack shaft assembly. Have yet to find the engine I really want but have gotten a Briggs and Stratton 11 HP single cylinder with electric start and 2 340 twin cylinder snowmobile engines that I may go ahead and use. Have also thought of making a "trial" version first using an actual antique bicycle frame beefed up and modified using the 11 HP motor like the first actual board racers used.
 

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Vintage bike addict
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Oh boy! Lot's of nice toys..er tools! Can't wait for the ribbon cutting!
 

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Vintage bike addict
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Man those guys do some work!
 

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Discussion Starter · #15 ·
I don't think my wife and kids would approve of living on welfare for a couple of years while I got that involved.
 

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Living Large-down from XL
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There went two hours... Brodie does some amazing work, doesn't he? That site is like some sort of drug... Crack for the m/c enthusiast!

Beautiful workmanship.
 

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Vintage bike addict
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There went two hours... Brodie does some amazing work, doesn't he? That site is like some sort of drug... Crack for the m/c enthusiast!

Beautiful workmanship.
Yep ! at least two hrs.
 
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