Powertech RXB 4

evin268fs

Petty Officer 2nd Class
Joined
Nov 22, 2006
Messages
100
Any thoughts on this prop on a Stratos Fish and Ski? 13.25 Diamter seems small compared to the 13 and7/8 with my Viper, just cant get that dialed in perfectly, Had a 17P with Cup added, could still over rev, 19P Worked, could only get 5600, repitched to 18 and it overrevs, thinking the powertech 4 blade may be the ticket, to get a little more lift, a little more acceleration and keep my speeds relatily the same.

48 GPS best ever, 19P by myself
47 GPS repitched to 18 with two people, cant trim up all the way without overeveing, better holeshot
45 GPS with 17 P awesome holeshot

Wanting the RXB to run 45-47, carry a load a little better, accelerate a little harder, get the RPMS down a tad.

Also going to add a holeshot plate to the jackplate, and a foil just for good measure, slaloming is important. Also, smart tabs don't fit the notch transom, already tried. Can slalom already behind the boat, but you can never have enough out of the hole right?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Powertech RXB 4

You didn't mention what motor you have but generally speaking the 13 1/4" diameter props have a barrel suited for the 4 1/4" gearcase found on most 3 and 4 cylinder motors.

If you have an Evinrude as suggested by your screen name, the V4 props have 13 splines and V6 props have 15.
 

evin268fs

Petty Officer 2nd Class
Joined
Nov 22, 2006
Messages
100
Re: Powertech RXB 4

Evinrude 115 V4 60 degree looper, trying to prop for 6000 by myself, seems to want to run 5600 when I had the 19 P with two people, 6000 no matter who is in the boat with the worked 17 P, 6000 with two people and a quarter trim left with the 19 worked down to 18, only asked the prop shop to give me 200 rpms.

Seems there may be a lot of power in this engine from 3500 to 5000 and then again from 5800 to 6200 if that seems possible, was told to keep it at or below 6000 at full trim and WOT, have been told for a fish and ski that with the props I am running I am getting very good numbers

Also tried a 20 P Raker, dog out of the hole, could only turn it 5500 but had 4 in the boat

About 5" below the pad, would have tried to go higher with the raker, but got a huge rooster tail and lost lift at full trim, cant lose lift with the worked Vipers
 
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11rufus11

Seaman Apprentice
Joined
Jul 9, 2008
Messages
31
Re: Powertech RXB 4

Just my two cents. I too recently went through the trial and error process of finding a suitable prop for my Javelin Venom 17 f/s with a Johnson 115 V4 looper. The motor has a recommended rpm of 4500-5500 rpm at wot. It seems like a similar setup to yours. I tried a 17 pitch and 19 pitch Viper and also a 20 pitch Raker. The Raker was a dog out of the hole and I got only 4900-5000 rpm at wot. I wish I could have gotten a hold of a Raker 18p to try, but the shop did not have one. The Viper 17p was awesome out of the hole but rpm approached 5600-5700 rpm. OK, but I am scared of going over the high rpm rating. The 19p gave me a good hole shot and 5300-5400 rpm at wot. Top speed 50 mph. I went with the Viper 19p. I use the boat 75% fishing and 25% ski/tubing. I was torn between the 17 and 19 pitch prop until I bid and won a brand new Viper 19p on ebay for $150. Lovin' it. :)
 

evin268fs

Petty Officer 2nd Class
Joined
Nov 22, 2006
Messages
100
Re: Powertech RXB 4

11rufl- If it is indeed a 115 looper, check the plate on the motor/tilt/trim bracket, it should be rated 5000-6000 rpms, sounds good, before I had the jackplate I had the motor mounted one hole up, that could get you a few more rpms. Yes the19P Viper is the best prop I have found so far. Also, the Javelen and the Stratos are nearly identical depending upon the year.

Are your speeds GPS, becuase I was having to turn 5600 with the 19P Viper to get the speeds I got in the summer, the best ever 49 was in cold conditions and 6000 rpms
 

11rufus11

Seaman Apprentice
Joined
Jul 9, 2008
Messages
31
Re: Powertech RXB 4

Yes Evin, the motor rpm's are 4500-5500 as stated on the sticker. It can be confirmed at: http://www.outboardmotor.net/motors/184.html if you want to check it out. The speed was checked by GPS about 2 weeks ago after I sea foamed motor, checked carbs, and new spark plugs. The weather was clear, 74 degrees, 5mph winds, and calm water. I simply love the Javelin quality and smoothness on the water. I have been told by a trusted outboard mechanic that I need to keep the wot rpm's at the 5500-5600 range to help prevent carbon build up. That is why I was torn between the 17p and the 19p prop. The 17p performed more in that range but I couldn't pass up the deal on the 19p Viper on ebay. When I bought the boat from the original owner it had a Quicksilver 13 X 18 prop on it to replace the original Raker and I could only get 45 mph tops. My setup now is a great performance boost.
 

evin268fs

Petty Officer 2nd Class
Joined
Nov 22, 2006
Messages
100
Re: Powertech RXB 4

The plate on the trim bracket and my manual say, 6000 max, maybe because it is the inturder version?
 

evin268fs

Petty Officer 2nd Class
Joined
Nov 22, 2006
Messages
100
Re: Powertech RXB 4

Purchased the powertech in an 18P with 3/8 porting, should be able to try next weekend

Will be interesting to compare to the Viper props, looking for enven more holeshot, even better load carrying ability and 47-48.
 

stingraymax

Petty Officer 3rd Class
Joined
Sep 11, 2004
Messages
93
Re: Powertech RXB 4

How did the powertech do ??? I am considering one too
 
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