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.
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.
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.
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.
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.
6. Remove the 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.
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. Allow brake cable slack. Use a 5 mm Allen wrench to loosen the cable pinch bolt around one full turn at the brake caliper, enough for the cable to move through the bolt, but not so much the bolt and hardware comes off.
8. Align the slots in the barrel adjuster, at the brake lever. Twist the barrel adjuster and lock nut so the slots in them align, and ensure they are in-line with the slot at the front of the brake lever.
9. Remove the brake cable from the lever. Pull the brake cable housing out of the brake lever, then squeeze the brake lever back towards the bar to reveal the cylindrical brake cable stop. Lift the cable stop up and out of the brake lever to free the cable end.
10. Remove the old brake lever. Use a 5 mm Allen wrench to loosen the brake lever clamp bolt on the underside of the lever body, then slide the lever off the handlebar end and discard.
11. Install the new brake lever. Slide the new brake lever onto the handlebar end. Align the lever at the same angle as the brake lever on the other handlebar end, and use a 5 mm Allen wrench to tighten the brake lever clamp bolt. Torque to 6 Nm.
12. Install the brake cable end into the new lever. Ensure the new brake lever’s barrel adjuster and lock nut are oriented so their slots align with the slot at the front of the brake lever. Squeeze the brake lever back toward the handlebar to reveal the hole for the cylindrical cable stop. Slide the cylinder into the hole and pass the cable through the slots at the front of the lever, adjustment nut, and barrel adjuster. Press the brake cable housing end into the barrel adjuster, and rotate the barrel adjuster and lock nut so they help hold the cable in place inside the lever body.
13. Add tension to the brake cable. At the brake caliper, pull the brake cable end so there is tension on the cable and simultaneously use a 5 mm Allen wrench to tighten the cable pinch bolt on the caliper arm. Torque to 6 Nm.
14. Squeeze the brake lever several times to fully seat the cable housing and test the brake cable adjustment. If the brake lever can be easily squeezed more than halfway to the handlebar (below, left), they need to be adjusted so they will have adequate room between the lever and the grip, when installed (below, right).
a. For small brake adjustments and fine tuning the brake lever feel, add cable tension by using the barrel adjusters located at the brake lever and/or at the caliper. Twist the lock nut to loosen it away from the caliper or brake lever body. Turn the barrel adjuster to add small amounts of cable tension (or cable slack) to dial in your preferred brake lever feel. Once the tension is dialed to your preference, tighten the locknut by twisting it away from the barrel adjusted until it is snug against the caliper or brake lever body.
Unlocked at caliper Locked at caliper Unlocked at lever body Locked at lever body
b. For large brake adjustments, typically to add tension to a brake cable, adjust the cable at the caliper. At the caliper arm, use a 5 mm Allen wrench to loosen the cable pinch bolt just enough to allow the cable to move (but not so loose that the hardware comes off completely). Pull the end of the cable tight, slide the caliper arm slightly away from the cable end, and tighten the cable pinch bolt. Test the brake feel and performance; repeat if necessary. When complete, torque the cable pinch bolt to 6 Nm.
15. Reinstall the throttle. Slide the 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 clamp bolt. Torque to 3 Nm.
16. 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.
The spacer must be properly installed between the throttle and the handlebar grip for the bike to operate safely.
17. 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.
Notice: Ensure the grip end is flush with the handlebar end and the spacer and throttle are aligned as shown (below, at right).
18. Reconnect the brake-wiring harness connector and the throttle-wiring harness connector. Find the match for each of these connectors, align the internal notches and pins and external arrows and press directly together to full seat the connections.
Brake-wiring harness Throttle-wiring harness
19. Reinstall zip ties (if they were snipped) to organize cables. Snip off zip tie excess.
20. 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 email@example.com or by phone to (800) 939-0310 x 2.