I installed the Riva Stage I kit and it tops out at 68.9 on my GPS. I noticed the ski only did around 65 to 66 mph GPS stock. I have an 2nd RXP that seems to be about 1 to 2 mph faster when they were both stock. Is it common to have one PWC be about 1 to 2mph faster then the other? all test were done with the same fuel tank levels and test were done the same day. Why is it that one RXP seems to a little slower?

With my Stage I kit I also noticed my RPM's will bounce around 7950 to 8020 Depending trim position. I hope this infomation helps

It isn't "common", but at the same time not unheard of to have variations in speed and RPM between similar craft. It could be caused by any number of reasons. Hull, pump, engine, etc, etc.

Your RPM readings vary due to increased drag as you set the nose (trim down). That puts more load on the motor causing the drop in RPM. It's not a problem unless your RPM varies by several hundred or more.

I had the same problem. I had to re-pitch my prop to 1mm-2mm de-pitched with the Stage one to get 8100rpm at 71.8mph. Ride plate hole filled in.

How much is gained by filling the ride plate holes.

quote:

Originally posted by sled:
How much is gained by filling the ride plate holes.

1mph max. Most probably get about a 0.5mph gain on the GPS. It depends; again...every ski is different.