Prop for 90 1996 Johnson-Top speed w/ skier - Moderated Discussion Areas

  ContinuousWave
  Whaler
  Moderated Discussion Areas
  ContinuousWave: Whaler Performance
  Prop for 90 1996 Johnson-Top speed w/ skier

search | FAQ | profile | register | author help

Author Topic:   Prop for 90 1996 Johnson-Top speed w/ skier

jdwhaler posted 05-06-2002 08:17 AM ET (US)
What is the best prop for the 1996 Johnson 90 for getting top end speed while pulling a skier? The max speed I am getting pulling a skier is 31mph vs the max speed I get without a skier is 38mph.

russellbailey posted 05-06-2002 11:11 AM ET (US)
You need to specify the boat. If it is a 17' Sport/Montauk, that seems like a large decrease in speed for a single skier, so I'm guessing maybe you have a hull that needs more power like a Dauntless.
What is your peak RPM when pulling the skier? Is it pegged? If your boat is not powered by its maximum engine, you might need to underprop for normal operation to get good skiing performance - no big deal for normal operation except you have to watch the tach.
I can tell you that our 15' Striper 70 hp sees a minimal decrease in speed except when the slalom skier is cutting hard.
jdwhaler posted 05-06-2002 07:38 PM ET (US)
17 montauk.
russellbailey posted 05-07-2002 09:41 AM ET (US)
1. Do you know what RPM you are hitting with the skier, and what size prop you are using? If you are not getting to or close to max RPM, you need a smaller prop.
2. Are you hitting 31 with the skier right behind you, when skier is cutting hard, with slalom skier or two skis? Big skier, little skier?
I'm guessing since I don't know the answers to #1 or #2, but here are my guesses on props.
A - light load - 13x19
B - typical skiing - 13x17
C - heavy skiing - 13x15
maverick posted 05-07-2002 07:28 PM ET (US)
I've owned 2 different 17s, two different (and both new) 90HP motors. Each had a 13 1/4 by 17, and both were awesome out of the hole and ran wide open throttle (mostly unloaded) at about 47mph. I tried a 13 by 19 on the last 17', and it would not pull up a slalom skier, but had about 52mph top end. Both 13.25 x 17s were aluminum; the 13 x 19 was stainless. Mav
Whalerdan posted 05-08-2002 07:54 AM ET (US)
52 mph! Damn, I must be doing something wrong! I have a 19 inch on a OMC '90 Montauk.
triblet posted 05-08-2002 10:44 PM ET (US)
Maverick: what brand 90's? The gear ratio
varies by brand, and that affects the required
prop.
Brand also affect diameter.
Chuck, who gets about 41 MPH from a '96ish
Evenrude 90 with a 14x17 prop, and nothing
on board but me and a couple of gallons of
gas.

Wild Turkey posted 05-08-2002 11:02 PM ET (US)
Mav:
I must not be living right...
I can only get 44 mph out of my Evinrude 90, 14x19 SS Rapture prop, CMC jackplate, light load & totally trimmed out.
Chris
maverick posted 05-11-2002 02:51 PM ET (US)
Yep, both 17s were very fast - both were not waterlogged, and both were early 1970s vintage boats...a 1970 and 1971 if memory serves. The new motors were: a 1987 Evinrude 90, and a 1991 Johnson 90. You guys that can't get much speed - I really don't know what to tell you. Are your 17s the newer style perhaps? I ran nearly the same speeds in both fresh and saltwater (unloaded). One of the boats that I sold 5 yrs ago is still in use on Clarks Hill Lake (Georgia) - talked to the guy 2 weeks ago. I doubt my GPS/speedo could be wrong on both boats...? Anyway, I'd choose 13.25 x 17 aluminum for best all around prop. Mav
maverick posted 05-12-2002 08:38 AM ET (US)
One other thing I forgot to mention - on both 17s, I ran a lot in the Keys, and the alum props were worn down a bit from the sand (slightly smaller diameter). Motors cranked some RPMs - didn't have a tach but I'm sure it was up there - they'd scream pretty hard. Mav

Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.

Author	Topic: Prop for 90 1996 Johnson-Top speed w/ skier
jdwhaler	posted 05-06-2002 08:17 AM ET (US) What is the best prop for the 1996 Johnson 90 for getting top end speed while pulling a skier? The max speed I am getting pulling a skier is 31mph vs the max speed I get without a skier is 38mph.
russellbailey	posted 05-06-2002 11:11 AM ET (US) You need to specify the boat. If it is a 17' Sport/Montauk, that seems like a large decrease in speed for a single skier, so I'm guessing maybe you have a hull that needs more power like a Dauntless. What is your peak RPM when pulling the skier? Is it pegged? If your boat is not powered by its maximum engine, you might need to underprop for normal operation to get good skiing performance - no big deal for normal operation except you have to watch the tach. I can tell you that our 15' Striper 70 hp sees a minimal decrease in speed except when the slalom skier is cutting hard.
jdwhaler	posted 05-06-2002 07:38 PM ET (US) 17 montauk.
russellbailey	posted 05-07-2002 09:41 AM ET (US) 1. Do you know what RPM you are hitting with the skier, and what size prop you are using? If you are not getting to or close to max RPM, you need a smaller prop. 2. Are you hitting 31 with the skier right behind you, when skier is cutting hard, with slalom skier or two skis? Big skier, little skier? I'm guessing since I don't know the answers to #1 or #2, but here are my guesses on props. A - light load - 13x19 B - typical skiing - 13x17 C - heavy skiing - 13x15
maverick	posted 05-07-2002 07:28 PM ET (US) I've owned 2 different 17s, two different (and both new) 90HP motors. Each had a 13 1/4 by 17, and both were awesome out of the hole and ran wide open throttle (mostly unloaded) at about 47mph. I tried a 13 by 19 on the last 17', and it would not pull up a slalom skier, but had about 52mph top end. Both 13.25 x 17s were aluminum; the 13 x 19 was stainless. Mav
Whalerdan	posted 05-08-2002 07:54 AM ET (US) 52 mph! Damn, I must be doing something wrong! I have a 19 inch on a OMC '90 Montauk.
triblet	posted 05-08-2002 10:44 PM ET (US) Maverick: what brand 90's? The gear ratio varies by brand, and that affects the required prop. Brand also affect diameter. Chuck, who gets about 41 MPH from a '96ish Evenrude 90 with a 14x17 prop, and nothing on board but me and a couple of gallons of gas.
Wild Turkey	posted 05-08-2002 11:02 PM ET (US) Mav: I must not be living right... I can only get 44 mph out of my Evinrude 90, 14x19 SS Rapture prop, CMC jackplate, light load & totally trimmed out. Chris
maverick	posted 05-11-2002 02:51 PM ET (US) Yep, both 17s were very fast - both were not waterlogged, and both were early 1970s vintage boats...a 1970 and 1971 if memory serves. The new motors were: a 1987 Evinrude 90, and a 1991 Johnson 90. You guys that can't get much speed - I really don't know what to tell you. Are your 17s the newer style perhaps? I ran nearly the same speeds in both fresh and saltwater (unloaded). One of the boats that I sold 5 yrs ago is still in use on Clarks Hill Lake (Georgia) - talked to the guy 2 weeks ago. I doubt my GPS/speedo could be wrong on both boats...? Anyway, I'd choose 13.25 x 17 aluminum for best all around prop. Mav
maverick	posted 05-12-2002 08:38 AM ET (US) One other thing I forgot to mention - on both 17s, I ran a lot in the Keys, and the alum props were worn down a bit from the sand (slightly smaller diameter). Motors cranked some RPMs - didn't have a tach but I'm sure it was up there - they'd scream pretty hard. Mav