Motorized Bicycle Laws

This spark plug color chart will help you determine if your motorized bicycle engine is running too cold or rich, or too hot or lean. Simply compare the color of your spark plug with those shown on the chart below. Click the Download button for a higher resolution uncompressed image. Reference: https://motoredbikes.com/threads/tuning-plug-color.58000/post-529953

A short guide to installing a motorized bicycle engine on a Trek mountain bike by Tom. This is an overview of the kit that is installed on my Trek mountain bike. Total install time: About 3 hours. I bought this kit from eBay; it was close to $150 after tax and shipping. It pretty much included all the parts to get my bike going. First thing I did was install the sprocket to the left side of the rear wheel. This is not very technical, but a little tedious. This sprocket is fixed to the...

HT is short for “Happy Times”. The Happy Times engines are 2 stroke engines manufactured in China. HT Engine Specifications Click here for the technical specifications of a HT motorized bicycle engine. 2 Stroke Kits The HT engine is a 2 Stroke engine with an NT carby. This is the most popular setup for motorizing a bicycle and generally the cheapest option too. 2 Stroke kits require oil to be added to the gas tank. 4 Stroke Kits The following picture is of a 4-Stroke motorized...

This guide shows you how to easily remove & replace the drive sprocket on a motorized bicycle engine. 1. Remove the pin from the center of the drive sprocket to start with. You can also remove the ball from behind the pin. 2. Take an extra chain link and jam it in between the sprocket and the engine case (shown in the picture above). 3. Use the correct socket spanner to remove the bolt. It takes some force to loosen the nut. Remove the bolt and the jagged washer. Drive Sprocket...

This is a basic guide showing some key points to remember when motorizing a bicycle. 1. Mounting the Motor Put the motor on the frame upright and make sure that its sitting straight and that it also clears the chain wheel and or chain guard. Also to make sure to use the new style steel flat motor mounts not the old style cast aluminum ones the new style ones flex around the motor studs and make for a tighter fit. Do not over tighten motor studs. If down tube is to small use the frame...