# Cupped Stainless Prop Question



## NealXB2003 (Jun 8, 2020)

Mine had a noticeable knock at low speed until I went to a different (softer) hub.


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## BrownDog (Jun 22, 2019)

some engines just dont like a certain RPM range.


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## TheAdamsProject (Oct 29, 2007)

I had quite a bit of chatter with a heavy cupped Foreman prop when testing it. Once you would get above idle it was quiet and smooth.


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## jay.bush1434 (Dec 27, 2014)

Actually very common with heavy props and also props with heavy cup. There is actually a lot of discussion about this.


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## Smackdaddy53 (Dec 31, 2012)

Yes


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## Ruger (Feb 20, 2018)

🤔 Well, guess that's the way it is. I don't like all the racket but, I need the prop. Thanks again for the information!


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## Smackdaddy53 (Dec 31, 2012)

Mine is a three blade XXX cup on a Yamaha 70TLR. Vibrates at anything lower than 2000rpm then smooth as butter anything over that. It’s been on it over three years and if it was a problem my bearings would be shot by now.


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## FSUDrew99 (Feb 3, 2015)

TheAdamsProject said:


> I had quite a bit of chatter with a heavy cupped Foreman prop when testing it. Once you would get above idle it was quiet and smooth.


Same here and drove me crazy... Im just used to it now.


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