Forward to 50 seconds? And miss all that boat porn? Surely you jest! Great video! - Jim On Sep 23, 2015, at 4:24 PM, Dave Scobie <scoobscobie@gmail.com> wrote:
Jim:
i've motored against 4kts with a Suzuki 4HP. i know this as i know the setting for a set speed (i usually cruise with motor at about 4.5 knots). GPS says i'm going .5 knots i know the current is about 4kts.
i've pushed a Sage 17 against current with a Honda 2. see this video and forward to 50 seconds.
i was running the motor at 4/5th throttle. this will set a Sage 17 at about 4.8 or 5 kts. in the video i'm going 1 to 1.5 knots over ground. i usually set the motor at 2/3rd or so and cruise at 4.5 kts.
motoring into a headwind the experience will be different as besides current you have wind resistance of the hull and standing rig. once on my folks' Cheoy Lee 32 the wind was blowing so hard the boat couldn't overcome the resistance (boat had a 35-40 HP inboard diesel). in situations like this the question becomes - why are you motoring? you should be sailing.
-- :: Dave Scobie :: former M15 owner - www.freewebs.com/m15-named-scred :: M17 #375 SWEET PEA - www.m17-375.webs.com
On Wed, Sep 23, 2015 at 3:16 PM, James Poulakis <picfo@comcast.net> wrote:
So can a 2hp Honda push a loaded (say 2500#) M-17 at its 5.5 knot hull speed against a 4 knot current? I’m hoping it will because I’m tired of doing the “clean and jerk” with my 60# 4hp Mercury.
- Jim M-17 “Spirit”
On Sep 22, 2015, at 3:49 PM, Dave Scobie <scoobscobie@gmail.com> wrote:
i'm writing this to assure it is part of the discussions about motor size for the M15, M17, M23, Sage 15 and Sage 17.
these are all displacement hulls that have a hull speed (about 5.2kts for M15 and S15, 5.5kts for M17/S17, and 6.5 for the M23).
the Montomery and Sage hull shapes are not planing type. you may get a little past hull speed but not get the boat on a plane with more horsepower (you will make a bigger wake as the boat tries to climb the bow wave).
so, a larger horsepower motor will not allow you to overcome a current greater than hull speed.
yes, with more horsepower you can overcome wind and get a little help overcoming waves ... but not against current as this is constrained by the boat's hull speed (unless you can get the boat on a plane).
-- :: Dave Scobie :: former M15 owner - www.freewebs.com/m15-named-scred :: M17 #375 SWEET PEA - www.m17-375.webs.com