Motorized Bicycle Performance Parts

CR Machine is a custom machine shop that specializes in offering the highest quality parts and engines in the industry.

All parts are meticulously inspected: Machining errors are corrected. Parts that are not correctable are scrapped.

Please allow several days to several weeks for Fred to complete your order.

Our products are intended to be sold only to end users of the product. 

CR Machine incorporates innovative technology in the products it sells.

In order to purchase from CR Machine, you must agree that your purchase will NOT be used as a sample for reproduction.

Theft of our technology may result in prosecution, as it violates the terms of sale.



GT-5 SUPER bottom end assembly GT-5 Super engine with 21mm carb
GT-5 SUPER bottom end assemblyGT-5 Super engine with 21mm carb

GT-5 SUPER racing bottom end assembly

GT-5 Super with hammer intake and 21 mm carb.

NOS Tightcase motor, 21mm PHBG GT-5 SUPER Racing engine
NOS Tightcase motor, 21mm PHBGGT-5 SUPER Racing engine

40mm stroke tightcase motor with 21mm carburetor!

NEW! GT-5 SUPER Race engine


GT-5L race engine MPG-38 engine, NEW
GT-5L race engineMPG-38 engine, NEW

The amazing GT-5L powerhouse! Limited stock!

New MPG-38 engine for stock exhaust