croakersmoker Posted December 29, 2022 Report Share Posted December 29, 2022 Hey all, Looking for some input here for my bayfisher. It's a pretty well loaded boat with a large bow platform, 24v iPilot, power pole, etc. After repowering, I am getting some pretty great numbers, but I think I have a little room left to tinker. The Yamaha website says the wide open throttle rpm range is 5,000-6,000. Not much help... All props are 13.25" Powertech SDC 3 series. The motor came with a 3 blade, 17p. I quickly moved to a 3 blade 19p. Here's the numbers: 17p: 4800 rpm-27 mph 6,200rpm rev limiter-37mph Incredible grip when turning, violent hole shot 19p: 4800rpm-31mph WOT-45 mph. I can hit the rev limiter at 6,200 rpm when I trim the motor correctly. It grips well in the turns and shoots out of the hole well enough. I am curious if I need to try a 21p prop. Should my WOT really be well under 6,000? I tend to run deeper water, so I'm looking for speed and economy over hole shot. I have a bit of a lead foot and often find my cruising rpm increasing to near 5,200 to stay around 35mph. I have been told a few times that cruising in the low to mid 5,000 rpm range won't damage the motor, and my fuel economy doesn't really change between 4,800 and 5,200. I really notice the point of entry moving back when the boat gets above 35mph, so I like to cruise there. Looking for input and REALLY looking to tickle that 50mph mark. let me know what you think. Thanks in advance. Quote Link to comment Share on other sites More sharing options...
searing Posted January 1, 2023 Report Share Posted January 1, 2023 On 12/29/2022 at 2:49 PM, croakersmoker said: Hey all, Looking for some input here for my bayfisher. It's a pretty well loaded boat with a large bow platform, 24v iPilot, power pole, etc. After repowering, I am getting some pretty great numbers, but I think I have a little room left to tinker. The Yamaha website says the wide open throttle rpm range is 5,000-6,000. Not much help... All props are 13.25" Powertech SDC 3 series. The motor came with a 3 blade, 17p. I quickly moved to a 3 blade 19p. Here's the numbers: 17p: 4800 rpm-27 mph 6,200rpm rev limiter-37mph Incredible grip when turning, violent hole shot 19p: 4800rpm-31mph WOT-45 mph. I can hit the rev limiter at 6,200 rpm when I trim the motor correctly. It grips well in the turns and shoots out of the hole well enough. I am curious if I need to try a 21p prop. Should my WOT really be well under 6,000? I tend to run deeper water, so I'm looking for speed and economy over hole shot. I have a bit of a lead foot and often find my cruising rpm increasing to near 5,200 to stay around 35mph. I have been told a few times that cruising in the low to mid 5,000 rpm range won't damage the motor, and my fuel economy doesn't really change between 4,800 and 5,200. I really notice the point of entry moving back when the boat gets above 35mph, so I like to cruise there. Looking for input and REALLY looking to tickle that 50mph mark. let me know what you think. Thanks in advance. Woww! With the 19p prop fully loaded reaching 45mph sounds pretty good to me and jealous:) I know it's totally different scenario with yours being a 4 stroke, I have a 90hp 2 stroke on my 2000 Bayfisher 16 with a Stilletto Y1315. I get 41mph @ 5300rpm completely trimmed out 2 people and loaded for fishing. I feel like there is room for improvement specially in the hole shot and corner grip department. I wish I could help but I'm pretty ignorant regarding props. I've been researching to learn all I can to maybe improve mine with a different prop. I'm not sure how right this is so I'm posting as much as a question than anything but from what I think I understand of the basics is a prop that allows you to reach somewhere in between your Yamaha's max RPM range at WOT is where you want to be. If unable to reach that range you maybe putting unwanted stress on the motors components, and if you're reaching max range easily you're giving away performance. With prop specs it all seems to be a give and take in the different areas of performance. Just hoping to learn. Happy New Year Dennis Quote Link to comment Share on other sites More sharing options...
geeviam Posted January 1, 2023 Report Share Posted January 1, 2023 On 12/29/2022 at 2:49 PM, croakersmoker said: Looking for input and REALLY looking to tickle that 50mph mark The new Yamaha 90 SHO is an impressive motor, and I think a different prop will help - but reaching 50mph is a long shot. Sending you a DM about a prop to try that is in limited supply. Quote Link to comment Share on other sites More sharing options...
croakersmoker Posted January 1, 2023 Author Report Share Posted January 1, 2023 @searing I saw 45 with me, the trolling motor, and a full tank. I usually can get to 43 with another person and my bow platform. 1 Quote Link to comment Share on other sites More sharing options...
geeviam Posted January 1, 2023 Report Share Posted January 1, 2023 36 minutes ago, croakersmoker said: @searing I saw 45 with me, the trolling motor, and a full tank. I usually can get to 43 with another person and my bow platform. Man, those are great numbers with a TM and full tank! You may be able to tickle 50 mph with a lighter load and upgraded prop. I love my Suzuki 90 but the more I hear about the new Yamaha 90 SHO, the more I think maybe the Yamy's got the edge. More displacement, same weight and that 2.33:1 gear ratio which is spot-on in my book. 1 Quote Link to comment Share on other sites More sharing options...
HoneyB Posted January 2, 2023 Report Share Posted January 2, 2023 I read this post before anyone posted a reply. I wanted to see waht others had to say before posting my initial thoughts. I think 50 mph is going to be a tall task for the numbers you are getting now. I think the fact that the motor is getting to 6300 rpm probably means it’s starting to slip as you trim it up. If you try a 21 pitch prop I would suggest looking for a prop that is vented to help you spin it up during your hole shot. I think the problem with getting more is the fact the diameter on the prop will always be limited. All that being said yes I get low 40’s on my old two stroke on my 2000 16 foot Redfisher. I run a four blade Mercury spitfire stainless prop mostly because it holds in turns better than any other prop I tried. 1 Quote Link to comment Share on other sites More sharing options...
searing Posted January 3, 2023 Report Share Posted January 3, 2023 On 1/1/2023 at 7:16 PM, HoneyB said: I read this post before anyone posted a reply. I wanted to see waht others had to say before posting my initial thoughts. I think 50 mph is going to be a tall task for the numbers you are getting now. I think the fact that the motor is getting to 6300 rpm probably means it’s starting to slip as you trim it up. If you try a 21 pitch prop I would suggest looking for a prop that is vented to help you spin it up during your hole shot. I think the problem with getting more is the fact the diameter on the prop will always be limited. All that being said yes I get low 40’s on my old two stroke on my 2000 16 foot Redfisher. I run a four blade Mercury spitfire stainless prop mostly because it holds in turns better than any other prop I tried. What hp and model 2 stroke are you running? Quote Link to comment Share on other sites More sharing options...
HoneyB Posted January 3, 2023 Report Share Posted January 3, 2023 My motor is a 2006 90hp 2 stroke yamaha. I have spent more time trying to find a prop that would not blow out in turns than finding wot speed. Quote Link to comment Share on other sites More sharing options...
searing Posted January 3, 2023 Report Share Posted January 3, 2023 57 minutes ago, HoneyB said: My motor is a 2006 90hp 2 stroke yamaha. I have spent more time trying to find a prop that would not blow out in turns than finding wot speed. That's interesting! It doesn't seem like you've lost much if any top end. Is your Redfisher a smooth side or lappy? I would love to know what Spitfire prop size or model # your running? Mine blows out real easy in a turn at speed unless I trim the motor down and that's even with the tabs all the way up. Mine is the Stilletto 1315 3 blade I got with it when I purchased it. Thank you Quote Link to comment Share on other sites More sharing options...
HoneyB Posted January 5, 2023 Report Share Posted January 5, 2023 I am running the spitfire x7 in 15 pitch. After realizing how well the lbs system works I would like to try a 17 pitch but just have not got around to trying to hunt one up. My boat is a 16 foot smooth sided 2000 year model Redfisher. Quote Link to comment Share on other sites More sharing options...
searing Posted January 6, 2023 Report Share Posted January 6, 2023 18 hours ago, HoneyB said: I am running the spitfire x7 in 15 pitch. After realizing how well the lbs system works I would like to try a 17 pitch but just have not got around to trying to hunt one up. My boat is a 16 foot smooth sided 2000 year model Redfisher. Thank you! Think we pretty much have the same boat. Sounds like you have the 1st year of the smooth side Redfisher 16. I had someone tell me once that the Bayfisher was first smooth side 16 in 2000 then it became the Redfisher 16 in 2001 and the Bayfisher 16 was no more starting 2001. I guess that was incorrect. I love how it fishes and rides for it’s size, I have no desire to change. Thank you again, Dennis Quote Link to comment Share on other sites More sharing options...
croakersmoker Posted April 5, 2023 Author Report Share Posted April 5, 2023 Sorry I went silent on this post for a while. I had a prop shop add some cup to the 19p 3 blade Powertech scd. The performance on the boat has been phenomenal since. Before I repowered, I had a similar issue with blowing out. I also had the dreaded spray that so many owners are familiar with. Now, I can't blow out on a turn unless I am trimmed high enough to throw a roostertail; and I slide like crazy at that point. No spray either! I have given up on my 50mph dreams, but here's the low down. 5,000rpm Cruise: 35.0mph 6.4MPG! 5,300 rpm 39.0mph 6,200 rpm 45.5 mph All runs are there and back with speeds averaged. Full fuel tank, myself (240lbs), and trolling motor. 1 Quote Link to comment Share on other sites More sharing options...
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