I worked on my Thumb Throttle last night.
Standard thumb throttles located to the left of the brake lever assembly, make for a long reach. Thumb throttles located between the grip shifter and the brake lever assembly move the brake lever to far left, two finger grab? I came up with a down and dirty solution.
The 3D printed Extension is affixed with dab silicone sealant inside the extension, then pressed into place and allowed to set.
“FOR A MORE ERGONOMIC THUMB THROTTLE LOCATION”
I am adding these 3D Part Renderings, along with a Screen Shot of the SLA 3D print generator. These renderings also shows a "Thumb Depression", that was added to the part (shown on the top-left side of the part).
I always start with a relatively clear 3D printed parts to check for fit/interference before the final part. It was important to see how the four small clips/ramps interfaced with the underside of the Thumb Throttle.
If you have access to 2017 SolidWorks and a 3D printer, send me your email address, and I will send you the part and SLA file. You may need to modify the part to fit the Thumb Throttle on your SONDORS bike.