I purchased a used Aventure 2 and the owner had installed a twist throttle on the right-hand side. I bought the bike thinking that I could just unplug the twist throttle and install the thumb throttle so it would be just like my Level 2. I found that the previous owner had cut the harness and soldered the wires for the twist throttle. I emailed Aventon and received a very quick response from Ned with the part number to order for a new harness. I wrote back asking if the harness came with installation instructions and was told it did not, but there was a UEL imbedded in the email that sent me to a site with complete instructions. I ordered, received, and installed the harness and it works great. Excellent customer service!