100 MPG Madness, Project Aprilia SR50 Part 5- More Power!
By Mike Kojima
In order to honor the tragic passing of the owner of Segway, James Heselden in a freak accident on a Segway, we will dedicate this story which also promotes alternative transportation and modding in a sort of different way to his memory and vision.
|We replaced our Leo Vince pipe with the Tecnigas RSII which is optimized for a big bore larger displacement engine. The Tecnigas has quality construction with a carbon Kevlar silencer.|
We have brought our high tech Aprilia SR50 scooter from a fairly low powered urban runabout, whose direct injection stratified charge 50cc two stroke was designed as much for greenness as for performance, to a practical suburban commuter whose acceleration and 55 mph top speed are fast enough for serious riding in cut and thrust morning commuter traffic.
|To meet European standards for teen drivers, our pipe came with these welded in restrictors. There were two, one by the exhaust port, another by the silencer. Of course we had to remove these for the pipe to actually work! The Tecnigas RSII pipe has a venturi in the stinger section to help improve the powerband. You can see the venturi section at the end of the tail cone here.|
However we wanted a little more, we feel that to handle rush hour traffic a little more top speed is in order to avoid being run over by the rat race. For safety someone on a scooter should take his position in a lane. They should also be fast enough so cars will not tailgate. To get to this point where our scooter would be able to fill most of the role of a motorcycle it needed a little more beans.
|The restrictors are removed by grinding out the spot welds with a die grinder. You could use a dremel tool as well. The restrictors are designed to be easily removable so this is not hard at all. Just don't damage the sealing surfaces.|
Our first step was to replace our Leo Vince exhaust with a Tecnigas RSII. Although the Leo Vince is one of the best exhausts for the stock displacement, the Tecnigas RSII was designed around a big bore engine with a larger internal volume and more aggressive tuning. With good quality construction and a carbon Kevlar silencer, the Tecnigas RSII looked very serious and ready to run.
|Can you believe that the holes in the restrictors are this small!?|