Zomby Zack an old school chopper from scratch


Zomby Builder

This project started with two donar bikes. A tandem, and an old beach cruiser I picked up in Pacific Beach. IMG_0668.JPG The tandem had a nice rear wheel with a big drum brake. I had the hub relaced into a 24 inch aluminum wheel, with a 3 inch wide Fatti O tire. Thanks to Sam at Hidden Valley bicycles in Escondido CA IMG_0821.jpg


Next I built the rear end using the tandem tubing & drop outs. This needed to be widened for the wide tire & chain clearance. I chopped the beach cruiser completely in half at the seat post. After eliminating the seat post there was a lot of room for the motor, and by rocking it back increased the rake for the front end. I welded another bottom bracket into the frame to house the internal jackshaft and used the weld on supports that came with the go cart jackshaft kit to support the other end of the axle.IMG_0783.jpg


Next I mounted the motor, a 49cc Chinese MOON (Mitsubishi Clone) 2 stroke with a CVT torque converter. This motor was a take off from a go ped I bought off ebay new for $199.00. I mocked up the rest of the bike & test drove it to make sure it worked.

I dis assembled the bike to the frame & had it powder coated gloss black. $110.00 at North County Powder coating in San Marcos CA.
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Ready for re assembly. I mounted the rear wheel to center & allign with the drive sprocket. Then the jackshaft was assembled


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Zomby Builder

Zomby Zack continued

This may take 4 posts to complete.

Jack shaft assembly IMG_0825.jpg

Freewheel adapter two sprockets IMG_0826.jpg

Freewheel adapter 1 sprocket IMG_0827.jpg

European 3 piece crank adapter for bottom brackets to house jackshaft bearings IMG_0828.jpg

Front view IMG_0829.jpg

Rear view IMG_0830.jpg

Rolling Chasis IMG_0832.jpgIMG_0837.jpgIMG_0833.jpg[/ATTACH]


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go you good thing

Excellent. The detail you have posted is great:D

Sweet looking bikes also.

Very well done.

Zomby Builder

Zacks Crank & pedal drive

I assembled the crank & chain drive to the rear, everything lines up well so far. The crank had to be wider on the right to clear the CVT / left side stock Grubee. I fabed the Crank & kicked the sprocket over to the right to line up with the jackshaft sprocket. I made another crank similar to this one & it has worked great for over 1 year. (see ZENA)




This really dry runs smooth. I will now finish the front end, hook up brakes, tighten everything, put the seat & pedals on, test drive with only the pedal drive to make sure all is well before installing the Motor.





Stay tuned.
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woohooo...nice post! i do believe he's got the "attach" code down proper :)

and...great info too...some very interesting theory happening here...thanks!! 8)

Zomby Builder

Zomby Zax Lives

Pedaled it like a bike. OK on the beach, but way too much work for a 6% grade. Crank up the Chinese 49 & well "Holy mother of bring the dog in, Honey I'll hook the muffler up tomorrow.

Runs like a dream. I have really been eyeing that Tanaka 4 hp motor....Def on the upgrade list.

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