RIVA Racing Offers RPM Kit For STX-15F

RIVA CREW · 10-24-2006, 04:39 PM

We are now offering a RPM Kit that provides improved acceleration and handling as well as an additional 5mph in top speed! For parts listings, performance data and pricing please click here.

dlski · 10-24-2006, 05:44 PM

As a 15F owner its great to see more kits for the ski but....

It is very frustrating when the manufacturers and retailers advertise different performance figures for the same or similiar parts.

The Riva advert states "Note: Stock intake grate was utilized for maximum top speed. R&D STXF intake grate part # 111-15001 can be used for increased hook up in rough conditions, but top speed may be reduced by as much as 2 mph (+/-) in smooth water"

However on R&D's site it states http://www.rd-performance.com/perfor.../performer.asp that the top speed increases by 0.5 mph using the grate. Also RIVA using "2 mph (+/-)" is a very large variation it could be 0 or 5 mph I would have thought you could more specific.

I also don't understand how Riva can suggest using a 14/21, there are alot of people including myself that have tried a 14/20 and that was too tall for the ski even with mods. R&D are suggesting a 13/19.

I would really like to see some real world tests of both Riva's & R&D's kit.

AaronC · 10-25-2006, 09:29 AM

I'm using a 13.5/20 and I'm overspinning it. It feels like a car that's at the top of 3rd and looking for 4th gear. The acceleration is great, and that's what I asked for from impros. I will be giving a taller impeller a try. At least a 14/21 if not a touch higher. I think once I get the pump dialed in with bore size and adjust a thrust I will get everything I want out of the ski. I still have the exhaust to do as well. I really think 68 is doable with a couple additions to that RPM kit. I will find out in the next few months.

RIVA CREW · 11-03-2006, 06:56 PM

Our results vary only slightly from R&D's. They were obtained using a Stalker Radar gun backed up with a GPS and aftermarket tach. The combination of all the parts in our RPM Kit allow us to run the 14/21 in our conditions. If you live at altitude, ride in the ocean primarily or know you will be hauling a lot of weight (taking a family day trip) then you will need to adjust accordingly (a lighter prop). The test results we provide are optimum performance while maintaining reliability. We have a magazine test lined up for next spring.

dlski · 11-05-2006, 01:46 PM

Hi Riva
From your response I get the impression that your RPM kit was designed for fresh water use, single passenger. I ride mainly in the sea, single passenger in which case the R&D setup would probably give better results, lighter prop and scoop grate with not such a good top speed.

RIVA CREW · 11-07-2006, 10:50 AM

Our kit was designed to provide the best all around performance (including top speed) with the minimal amount of parts while maintaining reliability and not breaking the bank. Our kit will work in both fresh or salt water where we are located. If you ride where the water is known for being overly dense, with two or more passengers, or additional weight (extra gear/cargo) a 14/20 or 13/20 would be a better choice.

If you ride in the ocean primarily you'll need to go with a prop that suits your riding style. Meaning if you wave jump and play around you'll want a lighter prop than we recommend so you'll get better acceleration. If you like to ride long distances for extended periods of time then you should probably stick with the 14/21.

Our kits are a base to start with. Our sales staff or tech rep can help you tweak them to meet your specific needs, whether they are performance or financial.