Hop-Ups for Dummies - To Re-gear or not to Re-gear by Stanton High

Do You Need To Re-gear Your Bike?

Seems like a lot of people are forgetting some things after upgrading their engines. One of the best things after getting more power is feeling the newfound torque rip up the dirt beneath you. Seeing if you need to re-gear is easy and fun. From a complete stop, accelerate through the gears as fast as you can. If your motor revs to the point of shifting extremely fast, and your front wheel is lifting up to the point of no return by accident, gearing up is going to help performance A LOT! Try it going up an incline, in dirt, and/or on the street and you’ll start to feel how the engine is putting the power to the ground.

There are different sizes of front and rear sprockets, the stock Honda 50 gearing is 14 teeth in front and 37 in back. Put a bigger gear in the front and you will get more top speed, but lose torque. Put a bigger gear in back and you will lose top speed, but raise torque. On a big bore motor, you have a lot more power than on a stock motor, so you can gear it up and take advantage of the power and get a higher top speed!

The stock gearing will get about 35mph, I think that the gearing for the stock motor is right on for most people. If you are a small kid, or a really big kid (180lbs+) gearing down from stock will help acceleration a lot. My recommendations for an 88cc bore kit are a 15t sprocket in front, and tune the power if needed with the rear sprocket.

Changing the front sprocket is easy if you loosen the 12mm bolts with the chain still attached and back wheel on the ground. Remember that a longer chain may be needed if you change the gears a lot. (subTIP-Chains: Keeping your chain properly lubricated and cleaned will put less strain on the motor, making you feel more power. Don’t forget to keep a fair amount of play with the chains adjustments, too tight can cause expensive damage.) Changing the rear sprocket is done with the wheel off of the bike using a 6mm allen wrench and a 14mm crescent wrench to remove the four bolts holding it on. Reassemble all the bolts with some blue or red Locktite to keep it all on.

Keep the rubber side down!
Stanton High

About the author: Stanton High has ridden on wheels for as long as he can remember. In 2003, he discovered the xr50 and was instantly hooked. Recently, Stanton was in a bad accident and half his body was burned. "It was hell," Stanton recalls. But after four months and 13 surgeries later he got back on the xr50 and is now riding harder than ever. These days Stanton rides as much as he can and is looking for a job in a machine shop. You can check out some of Stanton's riding in the Rider Gallery.