Does this work? From hauck power sports. I have no idea if it will be a good investment or not. They said i could get 2-4 mph more w/ it.
Also you have to be using a hauck helix
my first post should help, Also you can use the search in this forum button on the top right of the page, click on it and type in what ever you want to read on there a a ton of info in the search feature
there is a guy in nova scotia that tested them with no luck he races rx1 he says its loses in the middle with no gains gear it properly and you will be fine