Bike Handlebar Twist Throttle

This is a twist grip resistive throttle intended as an accessory for the Bicycle BoosterPack (Project seen here: http://bit.ly/28XhHxg), shown in use on the new BoosterPack Mini. It clamps to a .875" diameter handlebar. It uses a potentiometer taken from a servotester.

Orient the parts right and you wont need any supports.

Vitamins:
(1) Servo Tester https://www.amazon.com/4-8-6V-Tester-Consistency-Master-Checker/dp/B00SYEEMVW/ref=as_li_ss_tl?ie=UTF8&qid=1449796973&sr=8-4&keywords=Servo+Tester&linkCode=sl1&tag=engin09-20&linkId=cb41643a07078d2137ca6aad0aa001e1

(1) Spring http://www.mcmaster.com/#9287K215 OR http://www.mcmaster.com/#9271K638

(1) #8 pan head machine screw, 1.25" long, with nut.

video links:
https://youtu.be/IPMHUKGsd10
https://www.youtube.com/watch?v=BeMnR_YpMvw