# Prop help Yamaha 2 stroke 70



## Austin Bustamante (May 11, 2015)

hey guys. Just got a new to me skiff and it has the wrong prop. What are you guys running on a 70 2 smoke

Current specs:
Caimen HP with 6” jackplate
70 hp Yamaha with 69 hours
Currently has a powertech RED 3 blade 17 pitch. Which seems massive.
Current wot is 4800-5000rpm 34-35mph feels like it’s lugging the engine.
Can only run it to 2.5” on the jackplate is it’s the motor trimmed completely down otherwise it blows out. In fact if the motor has any trim other than completely down it blows out.
Just wondering if anyone is running a similar setup. I am going to rob my other skiffs scb 3 blade 13p and see how it spins that to get another baseline on a skiff sized prop.
Thanks in advanced.


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## Smackdaddy53 (Dec 31, 2012)

2001 Yamaha 70TLRZ 4” JP 14” diameter 14 pitch XXX cup three blade Foreman Custom made for straight up shallow water holeshot but also hits 33-34mph with three people on my Maverick HPX Tunnel.


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## Bruce J (Mar 4, 2018)

Smackdaddy53 said:


> 2001 Yamaha 70TLRZ 4” JP 14” diameter 14 pitch XXX cup three blade Foreman Custom made for straight up shallow water holeshot but also hits 33-34mph with three people on my Maverick HPX Tunnel.


I have a Powertech XSB (I think) 4 blade, 15", ported prop that was originally intended for my F70/Maverick HPXT, but it was a little too much prop and I only used it once or twice. It might be a very good fit for a 70 2-stroke. If you're interested in saving some bucks over a new Powertech or Foreman, let me know. But I agree with Smackdaddy that the Foreman would be a more sure bet.


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## not2shabby (Sep 14, 2016)

Here's what I'm running on my HB 17.8 & 70 TLR - 

PowerTech Shallow Water Wheel (SWW) with custom cup. PT Prop number SWW3R16PYM90. Two guys (340lbs total), 12 gallons of fuel, normal gear.

30 mph @ 4800rpm
32 mph @ 5100
36 mph @ 6000

It will slip a little bit if I over-rev with the jack plate all the way up. Otherwise, it's excellent.


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## TGlidden (May 24, 2013)

Might be the high speed jet in the carb, not the prop. I could get 5,500 with a 13x17 four blade on a ‘09 70tlr. A Foreman three blade would hit 5,800 and 38.7mph. With a clogged high speed jet it acted just like yours, wouldn’t get over about 5,000.


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## Austin Bustamante (May 11, 2015)

TGlidden said:


> Might be the high speed jet in the carb, not the prop. I could get 5,500 with a 13x17 four blade on a ‘09 70tlr. A Foreman three blade would hit 5,800 and 38.7mph. With a clogged high speed jet it acted just like yours, wouldn’t get over about 5,000.


I will check. I just bought it used with low hours. Sounds very possible


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## TGlidden (May 24, 2013)

Yeah, used with low hours can mean carb issues. But it’s not a big deal and that’s a great motor.


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## Austin Bustamante (May 11, 2015)

Bruce J said:


> I have a Powertech XSB (I think) 4 blade, 15", ported prop that was originally intended for my F70/Maverick HPXT, but it was a little too much prop and I only used it once or twice. It might be a very good fit for a 70 2-stroke. If you're interested in saving some bucks over a new Powertech or Foreman, let me know. But I agree with Smackdaddy that the Foreman would be a more sure bet.


thanks man, I found a Powertech scd that I am gonna give a shot.


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## damthemainstream (Apr 11, 2017)

Have you tried running with the jackplate all the way down and motor trimmed up? Sometimes you just need to find the sweet spot combo.


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## Austin Bustamante (May 11, 2015)

damthemainstream said:


> Have you tried running with the jackplate all the way down and motor trimmed up? Sometimes you just need to find the sweet spot combo.


Both my friend and I did. It seems that its just way to much pitch for that motor. Most people are running 13-14 pitch with that specific prop to get in the upper 5k rpm range.


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## Austin Bustamante (May 11, 2015)

Alright guys just a quick update so others can use this data if ever needed.
Went with an SCD3-16. Seems pretty much on the money, great holeshot and can run high on the jackplate. 5900rpms and 38 mph with both people sitting in the rear. Im guessing the prop must be closer to a 17p with those numbers.


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## Poonphish (Feb 23, 2015)

Bruce J said:


> I have a Powertech XSB (I think) 4 blade, 15", ported prop that was originally intended for my F70/Maverick HPXT, but it was a little too much prop and I only used it once or twice. It might be a very good fit for a 70 2-stroke. If you're interested in saving some bucks over a new Powertech or Foreman, let me know. But I agree with Smackdaddy that the Foreman would be a more sure bet.


How much for your prop??? You can text me 239-980-4336. Thanks


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## Bruce J (Mar 4, 2018)

Just saw this


Poonphish said:


> How much for your prop??? You can text me 239-980-4336. Thanks


I just saw this and sent you a text.


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