Hi there,i was wondering why there is an upgrade kit for the fx140 or the fx160 yamaha and there is noone for the rxp 155 or the gti 130/155.I also would like to know if i install and a pump wedge and an intake grate without installing an impeller how miles it will go faster and if i have any problems

There are a number of factors. The number sold, their performance capability, the only one other premiere model was the GP1300R, etc. When time permits we will try to get something together as far as a complete kit for them.

Typically with the wedge you can expect about 1~2mph gain, possibly more. With the Pump Wedge you should install our Top-Loader Intake Grate and VTS Extension Rod. You need the grate to prevent the unpredictable handling encountered when using the Pump Wedge with a stock intage grate. The VTS Extension Rod will allow you to trim the VTS down fully after installing the pump wedge.