If you lived in the north Houston suburb area I would have given you mine. I took mine off when new. The original has about one hour on it. And yes, you will need a grip with a smaller inner diameter.I just picked up a 2009 Rancher 420 and the previous owner replaced the thumb throttle with the a motorcycle style throttle. After a few test drives I’m looking to switch back to the thumb throttle. Unfortunately the previous owner did not have the original thumb throttle. I’m new to ATVs, and I am having trouble find a replacement thumb throttle assembly. Any suggestions? Any advice on switching this back?