3 blade or 4 blade? dropping pitch either way.

[sportrider]

I have a 1989 Maxum 2000xr powered buy a force 125ob, when I bought the boat it had a 13 x 17 mich match prop on it. I could tell it was over propped and dropped to a mich match 13 x 15p. I'm currently pulling 5100rpm at WOT and running 31mph on GPS with the boat loaded. (4 people 3/4 tank fuel, ice chests etc.) I am able to get up on skis behind the boat, but I know how to ski and kinda fight my way up. I'm attempting to get a bunch more holeshot out of the boat to help get the kids and wife up on skis. the engine is rated for 5500prm max so I should still be ok loaded at WOT if I drop to a 13p prop. when I dropped from the 17p to the 15p I gained 3-4mph on top and the holeshot was noticably better as well as the throttle response. should I just stick with a 3 blade and drop to a 13p or is the 4 blade the way to go? the way the boat responded to the 15p really woke it up, I'm hoping for the same effect again.

 

[floater212]

the 4 blade will give you more bite for turning and quicker hole shot. another prop you could try is a mercury high five, it has 5 blades but the smallest, I think, is a 17" pitch. talk about hole shot... wow. I'm sure there will be more input on here soon.

 

[floater212]

the 4 blade will give you more bite for turning and quicker hole shot. another prop you could try is a mercury high five, it has 5 blades but the smallest, I think, is a 17" pitch. talk about hole shot... wow. I'm sure there will be more input on here soon.

 

[SkiDad]

for the last few years I've been running the same 15p prop on my 125 and about 5000-5100 but at 38 mph - i had 2 of these props and had one turned down to 13p just about 1 month ago - if you want it to buy it from me shoot me a PM (if that even works) - it has a some paint missing from the re-pitching process but it great shape otherwise and did pull harder. If course this assumes you have a non-thru hub lower unit. I don't need it b/c I just switched to a 2:1 lower unit and that made the most change for me. I really didn't have any problem getting up on 1 ski with the 15p and just 4 people but when the boat got loaded up I could tell. Now with the 2:1 I think i could even swing a 17p pretty easily.

If you are looking for a new prop look at the Michigan Vortex prop in 13p - it will fit - but you need a hub kit.

And yes you should be OK on RPM. The only concern is that you are only running 31 mph - I'm not sure if you skiing on 2 skis or 1 - but if 1 you need to run at least 27 mph, so you will be running your engine all out when skiing with a 13p - not an issue but just mentioning it. if you are skiing on 2 skis then maybe you don't have the right size skis - that should be no issue at all with your current prop - should pop you up in 1-2 secs.

 

[Starcraft5834]

Sport, you will be very happy with a 4 blade prop...........especially for water sports,,, best application by far

 

[KYsean]

A 14P Mercury Spitfire 4 blade will have you in a great RPM range for that boat motor combo, give you great hole shot and top end. The price is great also. I've tried quite a few props and wouldn't trade the Spitfire for any other.

 

[sportrider]

UPDATE; we took the boat out yesterday, the kids brought along some friends. this was the first time we had 6 people in the boat. now I'm thinking I need to drop to an 11" pitch, with that number of people the engine at WOT would only pull 4400 rpm and the speed dropped to 26mph, when we pulled the kids tubing it dropped to 3800-4000rpm and I was lucky if the boat would plane out. they had fun still but 18-19mph with a tube and trying to whip them and dropping to 13mph is no good.