Throttle Replacement

mceclip0.png Read through these instructions and contact Rad Power Bikes Product Support if you have questions. If you are not confident in your ability to successfully and safely perform all steps, we recommend having the work performed by a certified and reputable local bike mechanic.


1. Gather the tools you will need: Flat head screwdriver, isopropyl alcohol, a paper towel, flat side cutters, 5 mm Allen wrench, 3 mm Allen wrench, and a torque wrench with a 3 mm Allen bit. 


2. Turn off the bike. Press the MODE button until the bike and LCD Display turn OFF. Use the battery key to unlock and remove the battery from the bike. Once the battery is removed, press and hold the MODE button on the LCD Display Remote until the LCD Display has remained off for a few seconds (it may flash on). This will ensure the electrical system is fully off and safe for maintenance activities.

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3. Slide the handlebar grip off the handlebar. The grip can be pulled directly off the handlebar end, so first try rotating and pulling to remove. If stuck in place, use the techniques below to remove the grip more easily:

a. Use a flat head screwdriver to pry off the handlebar grip end cap and set aside.

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b. Apply a small amount of isopropyl rubbing alcohol to a paper towel. 

c. Use the flat head screwdriver to carefully pry the handlebar grip away from the handlebar so there is a small gap between them.

d. While keeping the screwdriver in place, squeeze the paper towel against the top of the screwdriver so a small amount of rubbing alcohol drips in between the interior of the grip and exterior of the handlebar to temporarily lubricate those surfaces. Repeat squeezing rubbing alcohol between the grip and handlebar as needed. 

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e. Twist and pull the grip to slide it off the handlebar end and set aside. (If still stuck, mix a small amount of dish soap with a small amount of water and apply a couple drops at a time between the interior of the grip and exterior of the handlebar to lubricate. Once removed, use a clean damp cloth to remove all liquid and soap residue to prevent the handlebar grip(s) from moving while riding, which could cause a dangerous situation.)


4. Remove the spacer and set aside. Take note of the orientation of the spacer for reinstallation.

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5. Unplug the throttle-wiring harness connector. Trace the cable coming out of the throttle to the bulge in the cable (the connector). If needed, use flat side cutters to snip the zip tie(s). Grab the connector housing and pull directly apart without twisting to disconnect.  

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6. Remove the old throttle. Use a 3 mm Allen key to loosen the throttle clamp bolt, the bolt under the throttle and perpendicular to the throttle power switch (1, below). If needed, move the brake lever out of the way of the throttle bolt by loosening the brake lever clamp bolt (2, below) with a 5 mm Allen wrench and rotating the lever up or down to allow throttle bolt access. Once the throttle is loose, slide it off the handlebar end.

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Notice: To access the throttle clamp bolt (1), it may be necessary to first loosen the brake lever clamp bolt (2) (using a 5 mm Allen wrench) and rotate the brake lever out of the way.


7. Install the new throttle. Slide the new throttle onto the handlebar end. Rotate the throttle to the throttle power switch is easily accessible by the rider. Use a 3 mm Allen wrench to tighten the throttle bolt. Torque to 3 Nm.  

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8. Reinstall the spacer. Orient the spacer so it slides under the throttle and the portion perpendicular to the handlebar is between the throttle and handlebar grip. 

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mceclip22.png The spacer must be properly installed between the throttle and the handlebar grip for the bike to operate safely.


9. Reinstall the handlebar grip. Apply a small amount of isopropyl rubbing alcohol to the top of the handlebar end and then slide and twist the grip into place. Reinstall the handlebar grip end cap. Once the alcohol dries, the handlebar grip should be firm on the handlebar and should not easily move.

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Notice: Ensure the grip end is flush with the handlebar end and the spacer and throttle are properly aligned as shown (below, at right).

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10. Connect the throttle to the wiring harness. Notice the inside of each half of the connector is yellow on the inside with three small pins, an internal alignment notch, and external arrows. Align the notch and arrows and press directly together without twisting to fully seat both sides of the connector. 



11. Reinstall zip ties (if they were snipped) to organize cables. Snip off zip tie excess.

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12. Reinstall the battery, test the bike fully, and have your work inspected by a certified, reputable bike mechanic.


For questions or assistance, please contact Rad Power Bikes Product Support by email to or by phone to (800) 939-0310 x 2.