Fat Tire Bicycle Chopper

graucho

graucho

New Member
I loved this style of frame from the good people at Home - Choppers U.S., LLC which I bought and chopped it up as a template. I altered the shape slightly for my specific project. They really have beautiful quality frames if anyones interested.
 

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I collected a front wheel/rim and fork parts. Then found a 10" wide 22" tall rear tire. 12" rim. Also a drawback handlebar.
 

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Collected Axle parts. Combined with the tire to take a look.
 

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Had a lifan engine shelved from a few years ago from a smashed minibike. Set the tire an engine in close adjustment to take ruff measurements.
 

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Built the rear frame to wrap around the fat tire. Built the motor/jackshaft mounting plate. Found a headlight from a kids electric chopper.
 

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Came up with a jackshaft setup with a freewheel to the pedals. Built a chain tentioner bracket and positioned. I found a kickstand from my old stock.
 

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Found a embossed flame seat. Which I will be using that color sceme to paint the bike. Found a disk brake and mounted it to take a look. Checked motor mount position. Rebuilt the headlight to handle my 12v set up. Welded a license plate/tail light set up. Welded up a battery tray for my 12v rechargeable setup. Then "fished" all electrical wiring through the frame.
 

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Pulled the bike down to good old mother earth for the first time to check the tracking and ballance. PERFECT! Peddals like a dream. A few chain links need to removed. Handle bar head neck needs to be spun forward. Handled excellent for being 7ft 11in long. (Wider turns of course) I pulled it next to my daughters car to get a peek what 7ft 11in looks like. After the engine test run is done it will be unassembled completely for painting. Im sure ill need to fine-tune my sprocket ratios for speed concerns. More to follow.
 

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holy crapamoly! thats some pure magnificence sitting right there! my last thought was, braking? any idea? if i rode that thing tbraking would literally be the last thought i had!lol
 
Re: A few updates/additions

Thank you guys for the nice complements! Other than working on it in 0-10 deg. weather its been a fun build. (finally in the 35-40 deg now)

Found some braided stainless casings for the throttle and brake cables. Then welded on tabs to thread them through heading to the disk brake and engine throttle. (Not using zip ties this time like my other store bikes) All electrical wires will pass through inside the frame. Everything is in the raw stages and not adjusted for sagging or final cable lenght. Just a few quick shots.

Then found a set of caps to go onto the threaded rear axle ends. There very dangerous because of the pointed ends. I may have to shave 1/8 off of them so I dont stab myself. (It will happen) LOL. I have to keep them, im diggin the look.
 

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Alright Graucho, I hate you.
Is inertia a problem with that massive rear tire?
Is stopping OK also?
Righteous machine!
I hate you. :D
 
Howdy graucho. Man thats purty work. The rear wheel really looks BA.
Great link, they have some great stuff.


Weedylot said:
Alright Graucho, I hate you.
Is inertia a problem with that massive rear tire?
Is stopping OK also?
Righteous machine!
I hate you. :D
Click to expand...

Snork, snork. me 2
 
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Re: Ready for paint

Thanks very much for the Kudo's.

We had a little warmer temps the last 4 days so I totally disasembled the bike. Then I finished the bodywork and took it to primer. Now she sits to cure and waits for a 70 deg. day to paint. (Automotive sandable red oxide scratch filler primer. Sprayed with a wide nozzle airbruch pen)
 

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Still in the mid 30's here so no paint yet. I've been putz'in on the fuel tank and lighting issues. Here's what I came up with for the tank. It's only 34oz. I hope to get an hour out of it. I have room to expand if its a problem.
 

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