# 60HP Yamaha 2 stroke modifications



## firecat1981

The general consensus over the years here have been don't do it. Adding more power then what they were designed for with lead to you buying a new motor a lot sooner.


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## kingofsea

Got it. Thanks for the heads up.. I always wondered about it, and if it would even be worth it.


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## firecat1981

Only you can decide that. I'll just say this, there might be a reason the 70hp is a seperated class.


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## kingofsea

Thanks for your help! Would rather have the relaibility than speed.


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## No Bait / Lures Only

kingofsea said:


> Has anyone out there done any work/modifications on a 60HP 2 stroke Yamaha(2004)? I found a website out there called Hydrotec Marine Performance that sells big carbs, Exhaust tuner, fuel jets, and all gaskets needed to take your 60HP to around 80HP.
> 
> Anyone ever done this? Just wondering?





kingofsea said:


> Has anyone out there done any work/modifications on a 60HP 2 stroke Yamaha(2004)? I found a website out there called Hydrotec Marine Performance that sells big carbs, Exhaust tuner, fuel jets, and all gaskets needed to take your 60HP to around 80HP.
> 
> Anyone ever done this? Just wondering?


Yes I currently have 2 motors modified with Hydrotec parts, built 90>115 1987 on Hoog 16'8" and still in service, built 25>35 2006 currently on 17'6" Spear Glade X, run it 3-4 days per week. No issues at all with longevity or reliability. In addition the modded motors burn less fuel as the cruise speed is substantially higher than stock. Only downside is they require premium fuel vs regular for top performance. In addition I have a 18' Shipoke with a lightly modded Mercury 2.5 EFI 150 exhaust tuner, solid mounts, carbon fiber reeds. Runs great no premium fuel as no head modifications. All my motors are modded and no issues....


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## RunningOnEmpty

I did a hydro tec style modded yamaha. It was a fun project and fast. Probably won't do it again though. Buying a bigger motor is so much easier!


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## No Bait / Lures Only

RunningOnEmpty said:


> I did a hydro tec style modded yamaha. It was a fun project and fast. Probably won't do it again though. Buying a bigger motor is so much easier!





RunningOnEmpty said:


> I did a hydro tec style modded yamaha. It was a fun project and fast. Probably won't do it again though. Buying a bigger motor is so much easier!


You sounded disappointed, what motor did you modify?


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## KnotHome

The only difference in the 60 and 70 are the carbs. Wouldn't hurt to change those.


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## No Bait / Lures Only

Hydrotec modifies the bore of the carbs and the jets, not just a stock carb. Since 1990 I have had good experiences with their products. Company was Yamaha Rebuild/Warranty Center, and so lots of experience with stock and racing motors as well.


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## kingofsea

Thanks guys!! really appreciate all the input!


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## RunningOnEmpty

No Bait / Lures Only said:


> You sounded disappointed, what motor did you modify?


I wasn't disappointed at all. I had the 3 cylinder 30hp and it was almost as fast as the yamaha 50hp that replaced it. I will say that the 50hp had a much better gear case and the prop shaft size difference is huge. The little 30hp has a wimpy lower that's very fragile with a modded motor. The 50hp also gave me confidence to explore because it was stock and it turned less rpm's.


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## No Bait / Lures Only

RunningOnEmpty said:


> I wasn't disappointed at all. I had the 3 cylinder 30hp and it was almost as fast as the yamaha 50hp that replaced it. I will say that the 50hp had a much better gear case and the prop shaft size difference is huge. The little 30hp has a wimpy lower that's very fragile with a modded motor. The 50hp also gave me confidence to explore because it was stock and it turned less rpm's.


Still have the 50? If so you left it stock? Only drawback to the 25/30 lower unit is the delicate prop shaft, had to have mine straightened........cypress stumps are tougher.....


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## RunningOnEmpty

No Bait / Lures Only said:


> Still have the 50? If so you left it stock? Only drawback to the 25/30 lower unit is the delicate prop shaft, had to have mine straightened........cypress stumps are tougher.....


I straightened my 30 shaft 2 times. I kept the 50hp factory and only ran it a few times before selling it to a fellow forum member. Now I'm running a yamaha 200 hpdi while searching for a 250 or 300.


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## TheAdamsProject

If you were going to mod a yamaha with anything, the hydrotech boys are the ones to use. Lots of guys in the bass world use them and I dont recall them having any more issues than what just normally can occur with a stock motor.


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## No Bait / Lures Only

RunningOnEmpty said:


> I straightened my 30 shaft 2 times. I kept the 50hp factory and only ran it a few times before selling it to a fellow forum member. Now I'm running a yamaha 200 hpdi while searching for a 250 or 300.


Surly you are looking for a 2 stroke ? Rightttttt


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## RunningOnEmpty

No Bait / Lures Only said:


> Surly you are looking for a 2 stroke ? Rightttttt


I think I'm gonna stick with another yamaha hpdi vmax or a mercury optimax xs. I still love my 2 strokes.


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## ABoykin

The guys in Australia do it! Man I wish I could give these guys a call just to see how much HP they are getting out of these motors!


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## No Bait / Lures Only

RunningOnEmpty said:


> I think I'm gonna stick with another yamaha hpdi vmax or a mercury optimax xs. I still love my 2 strokes.


The motor of choice for racing is the 2.5 merc v6 as lots of them around to build up. Currently my shipoke 18 has a stock 1997 efi 2.5 merc and it tops 60 gps with a 4 blade prop. Still a little more speed with a 3 blade, handles good with the 4 blade.


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## RunningOnEmpty

No Bait / Lures Only said:


> The motor of choice for racing is the 2.5 merc v6 as lots of them around to build up. Currently my shipoke 18 has a stock 1997 efi 2.5 merc and it tops 60 gps with a 4 blade prop. Still a little more speed with a 3 blade, handles good with the 4 blade.


My 21 redfisher is setup with 5 batteries. I have no regrets on buying the 36v trolling though. I'm topping out at 50 mph while turning 5700 with a 2.6 200 hpdi 21 pitch power tech 3 blade. My cupping is worn down and my motor is cavitating. Have you ever tried a solas hr titan prop? I can get a 4 blade for under $300. I'm not looking into spending a bunch for a prop if I'm thinking about a bigger motor.


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