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Prop comparison

irish snowblower · 2018-06-21 19:51:41

I have a four meter rib with a forty horsepower Yamaha the prop on it is 11 3/8 x 12 but I made bits of it. When I bought the rib it came with a second prop but it is 11 1/8 x 13. On its current prop it is hitting 6000 rpm wot does anyone know what the effect will be if I change it to the second prop Thanks for any help

21-06-2018 08:51PM

#1

irish snowblower

Registered Users, Registered Users 2 Posts: 38 ✭

Join Date: January 2013

Posts: 33

I have a four meter rib with a forty horsepower Yamaha the prop on it is 11 3/8 x 12 but I made bits of it. When I bought the rib it came with a second prop but it is 11 1/8 x 13. On its current prop it is hitting 6000 rpm wot does anyone know what the effect will be if I change it to the second prop
Thanks for any help

0

Comments

#2 22-06-2018 07:28AM

fergal.b

Moderators, Motoring & Transport Moderators, Sports Moderators, Paid Member Posts: 6,385 Mod ✭✭✭✭

Join Date: July 2010

Posts: 6110

With the bigger prop you might get an extra MPH or two at the top end but a little slower take off speed, it should also bring your RPM down a bit as your a bit high at 6000 I believe 5500 is recommend for a forty hp.

.

0
#3 22-06-2018 09:06AM

irish snowblower

Registered Users, Registered Users 2 Posts: 38 ✭

Join Date: January 2013

Posts: 33

Thanks Fergal I will give it a try so I had a feeling my boat moving skills in hodson bay would pay off some day

0