I have the Sikk Toys 29cc chrome motor and have had both a Samba pipe and the FG pipe plus the two speed on a monster beetle. The Samba gives more top end power and the FG more on the bottom I took the two speed off because it was scary fast when it hit second. I like to run it with the FG pipe its way fast on top and will wheelie from a rolling start. It's fun to see how far you can wheelie with out getting it on the wing. I run 108 octane fuel mixed half and half with 92 octane pump gas. You can tell the differance between the 92 and the 100 octane its much more snappy. I bought from the Oneill brothers and have been very happy with their service and prices.