Got Bob?

ken /
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Finally started this bobber thing that's been kicking around my head for awhile out of leftover parts and scrap metal , pipe etc. Dumped my original version with the modified stepthrough frame and went full tube .

Wheelbase is 54" . Will run a fairly stock Tomos A3 engine with the Puch 22 cylinder and piston , just port matched and a Dellorto homemade expansion chamber .

Front fork is General 5-Star hydraulic with a relocated brake tab welded so I can use the A3 hubs and custom spacers. The hubs have sealed bearings front and rear (standard size - electric high speed motor ) 12mm YZ80 front axle front and rear. The wheels themselves are Motobecane 17" rims laced to Tomos A3 hubs for a 17" wheel that I won't have to down tooth (stock rear sprocket with 17" rim !! ) Triple tree is from a Suzuki XR75 and shimmed to fit the 26mm 5-Star fork tubes and the top tree bracket modified to fit the screw down forks (that was tough). I originally put the YZ80 forks and disk on there but that will be on the second frame out of my jig , so this one will be all low buck whatever I find . Front frame half is Suzuki SP100 dirtbike (had the right angles, sort of ) Funny , I found a set of tapered roler bearings at Walmart on clearance and they fit the headtube perfectly Back half is standard 1/2" mild steel tubing 0.95" wall bent and plated for the rear wheel. Handle bar shown is Yamaha ??? I think it was off my 550 Maxim . I think I might have found a way to make an internal throttle for about $10 , super simple design - no throttle cable !! We'll see. Brake will be single lever controlling both brakes ala BMX dually . Headtube angle/rake is 31 degrees for a trail of 3 - 4 inches hence the dirtbike frame . My next frame will use a standard streetbike frame for a 35 degree rake. I'm going to try to run a 12volt battery and GM electronic ignition (no kidding Honda/Yamaha guys do it all the time ) Don't really know if the GM ignition will allow 2-stroke RPMs but I have it setup and it's free so......

No front fender(maybe a small one to be legal) , bobbed rear fender off the Bullet A3. Frame is setup to use a 3.5" rear tire in the future , right now lil bitty 2.5's . Seat will be that modified bike seat from Walmart (bolted to bracket and top fender mount) with a pair of chevy valve springs for suspension. Engine will have left pedal arm unpinned and clipped to frame (removeable and pin can be reinserted in case I need to have the pedals actually work) Right pedal arm will be live to start it , then it too will pivot forward and clip into a mount , both pedals will face forward for foot pegs . There will be a fake oil tank below the seat for the battery and electronics . I need to figure out what to do with all the empty space below the tank . Possibly wind the expansion chamber up and back , I don't know depends on what else I find in my garage. Anyways - Feedback , both good /bad . Funny I just saw that 200cc Kikker Hardknock bike and thought crap I'm reinventing the wheel !! I have a Lifan 150cc engine with the upright cylinder that will go in bike number two that someone gave me , anyways I'd like to see if I missed any design cues from you crazies ! Suggestions ?? Let's hear them ..........

This single post is part of a larger thread. Start from the top or view this post in context.
Subject Written By Posted
  Got Bob?Topic by: ken ken 06/01/09 11:41PM
  Re: Got Bob?Re: ken ken 06/01/09 11:42PM
  Re: Got Bob?Re: ken ken 06/01/09 11:48PM
  Re: Got Bob?Re: Saabsonettguy . Saabsonettguy . 06/01/09 11:47PM
  Re: Got Bob?Re: ken ken 06/02/09 12:12AM

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