simo performance pipe's

So just a little update with out any pic's. so i paid 180 for a simo racing pipe from treats. I like it aot its a really good bike with a killer power band, but there is one thing not many people know about these bikes. They have a restictor in the header right before the chamber. Alot of people do not believe this and even treats say's there is non but with a little work and putting tubingdown the header till it stoped at the same spot and would not go father unless i moved it so it when in the restrictor.