Finding the best prop for 225 Yamaha 4 stroke

Discussion in 'Boats, Motors, Trailers and Towing Rigs Forum' started by Rayvon, Feb 18, 2020.

  1. Rayvon

    Rayvon Well-Known Member

    I'm currently running a 3 blade stainless 17P on my 215 Aquasport and it tops out at about 6100 RPM at about 40 MPH..Yamaha recommends running 5500-6000 RPM. I'd like to plane at lower speeds so I'm thinking 4 blade.Should I go up a pitch to 18P or stick with 17P because a 4 blade would decrease RPM on it's own? The Yamaha site has an "Offshore1" or an "Ultima4". Any experience with either ,or should I look for another brand than Yamaha?
    Last edited: Feb 19, 2020
  2. Battle Bay

    Battle Bay Member

    Watch those RPM specs, that engine should be between 5000-6000.
    Rayvon and gungadin like this.
  3. gungadin

    gungadin Well-Known Member

  4. fishin solo

    fishin solo Well-Known Member

    Ask @SteelyDan he is Ken from prop gods new apprentice.
    Rayvon likes this.
  5. cletus

    cletus Member

    Not sure what year yours is,but my 2009 that I had was 6100 rpm max.Propped it to run at 6000.
    Rayvon likes this.
  6. Rayvon

    Rayvon Well-Known Member

    Yes,your right about that,I don't know why I thought it was 6500.I cruise at 4000 and 26-28 mph.So I'm propped right for the 17P -3 blade,would the 4 blade increase my RPM in the same 17 pitch? If so,I'd need to go up to a 19P?
    Last edited: Feb 18, 2020
    g ram likes this.
  7. SteelyDan

    SteelyDan Well-Known Member

    I'd see if you can borrow a 15p mirage plus and try it or a SWSII in 15p. Also need to know the gear ratio of his leg to find out his slip % with his current prop.
  8. Rayvon

    Rayvon Well-Known Member

    Are there different gear ratio's on the 225 Yamaha 4 strokes? It's a 2004 model.Won't a 15P 4 blade increase my WOT RPM that is already at it's max?
  9. SteelyDan

    SteelyDan Well-Known Member

    I thought you wanted another 3 to 400 rpm as per your first post. If you want to stay at 6100 keep the same pitch in a 3 blade. You will probably want to drop 1 inch in pitch in a 4 blade. Powertech has an OFS4 in 1inch increments. I'd still see if you can borrow a mirage plus or salt water series II Yamaha prop in 17 pitch though before you decide to go 4 blade.

    Also your current prop is slipping 18.5% at WOT. You can definitely improve that. I'd try some bigger 3 blades first (which is what I recommended)
    Last edited: Feb 18, 2020
  10. Old Fisher

    Old Fisher Member

    If you want to cruise at noticeably lower rpm, I think you should consider a 4 blade prop. Much better out of the hole too. I like the Powertech OFS4 although there are other good 4 blade props too. You would need a 15P.
  11. Rayvon

    Rayvon Well-Known Member

    Off the Powertech website it looks like the best match would be a Powertech OFS4R16PCLY200 with a "cushion lock hub",a 16 pitch.They are $499 US @ "Propgods". I really want to try the 4 blade to get lower planing/cruise speed,hole shot ,stern lift and load carrying .My next question is who has the best pricing that you know of? All the web sites seem to be in U.S.A.
    Last edited: Feb 19, 2020
  12. Old Fisher

    Old Fisher Member

    When I bought mine, I found that it was hard to beat Ken's price and shipping terms at Propgods
    I don't know of any Canadian dealers that stock that prop.

    Rayvon, do you know the gear ratio of your F225?
  13. Rayvon

    Rayvon Well-Known Member

    No,I have no idea how to find the gear ratio.
  14. SteelyDan

    SteelyDan Well-Known Member

    I think its 2.00 gear ratio. I bought my powertech through Ken and had it shipped to Blaine. First I tried a 4 blade ofs4 but it made my boat porpoise so I sent it back and got a LFS3 which I'm really happy with.
  15. Rockfish

    Rockfish Well-Known Member

    If you are willing to buy local, I have heard that some of the local prop shops/suppliers have been known to let you borrow and try a number of props so that you get the one that works well with your boat and motor and you are happy with it.
    Rayvon likes this.
  16. Rayvon

    Rayvon Well-Known Member

    I would prefer to buy local,I'll try "Sherwood Marine". I'm still a little confused though,contrary to my original post when I thought I should be trying to get higher RPM,I should be looking to reduce my RPM to get between 5-6000 Rpm at full throttle. To reduce full RPM I thought I would go up in pitch from my 17P,but you guys are suggesting to go down to 15P or16P?
  17. Old Fisher

    Old Fisher Member

    If you were looking to reduce RPM by changing pitch on a prop of the same type and diameter, you would go up in pitch.
    but if you are thinking of trying a 4 blade prop, you will probably have to go down in pitch or the motor wont be able to turn it to the correct WOT rpm. You are currently running a 17P 3 blade prop and if you switch to a 17P 4 blade prop, you will probably lose too much rpm. for example, I'm running a 17P OFS4 on my F300 Yamaha and am getting about 5700 at WOT. You would need to drop to a 15P or 16P to get into the correct WOT range. I'm going to guess that the 15P would be the better prop for you
  18. uclueletcharters

    uclueletcharters Well-Known Member

    Trim Tabs make a huge difference. Your rpms seem about right a tad on the high side I like 5500-5800 full throttle I think you could go up a pitch to an 18 I believe it's 200 RPM drop per additional pitch when dialing in once your close. 15 pitch your motor will over rev hitting limiter if your hitting that high with a 17". Tabs will make a way bigger difference than a prop where your at and what your looking for imo. In the chop you can trim your nose right into it and lower planing speed down substantially.

    Many folks that fish and water ski have two different props, fishing and regular use a higher pitched prop and if skiing pulling people out of the water low pitch for the strong hole shot.
    Rayvon likes this.
  19. Rayvon

    Rayvon Well-Known Member

    I have tabs and use them all the time.Water skiing at my age could be deadly,fishing only.In my original post I said the 225 should be run at 6500WOT,which is wrong,I'll edit it.They recommend up to 6000 or less,my 17P 3 blade runs 6100 WOT. I can't see how running a less pitch 4 blade can bring my RPM's down to where they should be.I'm thinking "Uclueletcharters is right about going to an 18p -4 blade,but please enlighten me if I'm wrong,still confused.
  20. Old Fisher

    Old Fisher Member

    Remember that a 4 blade prop has more blade area than a 3 blade and is therefore harder to turn. If you swap out your 3 blade for a 4 blade of the same diameter, you will lose some rpm. The OFS4 4 blade prop has large blade area and fairly large diameter (15 1/4") so I don't think your 225 will be able to pull a 17 or 18P OFS4 to your desired rpm. I'm guessing you will need 15 or 16P if that's the prop you choose. There are lots of prop options with different blade designs and diameters and it can be a head scratcher to pick the best prop for your boat. I do like my OFS4 and think it's a good prop for boats like ours. I also tried a 14 1/2 X 18P four blade but it over revved and did not perform nearly as well on my F300 as the OFS4 prop.
    SteelyDan likes this.

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