The Grumpy Dumpies

This is my frankenbike of sorts, I gathered parts here and there from a couple of different mopeds and put them together to make this. Everyone wants a top tank bike right? That's what all the cool kids have. I figured that rather than picking up a stock top tank moped I'd make my own.I finally had enough stuff gathered over the winter of 2012-2013 to make it rideable.

I call it the Grumpy Dumpies because I built it while my wife and I had triplets. Thus my life was filled with grumpy dumpy diapers during the process (and still is).


Year Make Model
1978 JC Penney Pinto


Engine Manufacturer Engine Model
Puch ZA50
Engine Part Type Engine Part Name Engine Part Notes
Cylinder Kit Eurokit 47mm kit, angled port exhaust.

Fuel System

Fuel System Part Type Fuel System Part Name Fuel System Part Notes
Carburetor 21mm Dellorto PHBG
Main Jet 90
Idle Jet 40
Starter Jet 60
Needle W7
Atomizer 262 AU

Exhaust System

Exhaust Part Type Exhaust Part Name Exhaust Part Notes
Pipe MLM Rev Run Rev-Runs are no longer made, it's a great city blasting pipe. Mine is made for kits with an angled exhaust post, but the linked version is for a flat port.


Transmission Part Type Transmission Part Name Transmission Part Notes
Front Sprocket 20T
Rear Sprocket 40T 40t on the rear makes it easy for me if I swap the engine with an e50.

Additional Components

Part Type Part Name Part Notes
Front Suspension Kawasaki Kx80 Forks Shortened springs roughly 4"
Front Disc Brake Kawasaki kx80 Caliper and Rotor
Speedometer Trail Tech Vector

Custom Modifications

Modification Description
Chopped and braced seat post chopped, cross brace added. Bike was too low so I built a platform to raise the seat up and redid the cross bar.