And, the closer you get to theoretical hull speed, the power to go a bit faster increases greatly. It's not a linear graph. Swoops upwards steeply as you get up towards hull speed. Similar to other reports...my M17 will go 4 to 4.2 knots at about half throttle of my Honda 2.3 in calm conditions. Loses about half a knot in gusty headwinds and some chop. But back to calm conditions - after about 4.2 knots and half throttle, I will not get much beyond 4.5-4.6 knots even at near full throttle, because of that steep upward power vs. speed curve for the displacement hull. And as mentioned these small outboard props are shaped for planing boat speed at high throttle, or trolling kickers at low speed. Not ideal for pushing heavy displacement hulls. cheers, John On 11/6/21 8:46 AM, Sam wrote:
4.87 knts in theory, but it helps if you are going with the current!
http://www.msog.org/specs/race_ratings.cfm
On Sat, Nov 6, 2021, 3:49 AM Jim Sadler <jimsadler@jascopacific.com> wrote:
Any skippers know the hull speed of M15? My 2 hp will get the Pelican to 3.5 knts. To exceed hull speed would require that the vessel plane any exponentially more HP. That is my understanding Capt Jim
Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: casioqv <casioqv@usermail.com> Sent: Friday, November 5, 2021 7:24:51 PM To: For and about Montgomery Sailboats < montgomery_boats@mailman.xmission.com> Subject: M_Boats: Re: Outboard generator
Some small outboards can take an optional lighting coil or charge coil, it's an installable option on my 80s Yamaha 2hp. It produces a really small amount of current, designed to run nav lights, but might work with an autopilot depending on it's current needs.
Sincerely, Tyler
-----Original Message-----
From: Dave <scoobscobie@gmail.com> To: For <montgomery_boats@mailman.xmission.com> Date: Friday, 5 November 2021 9:35 AM PDT Subject: M_Boats: Re: Outboard generator
I'm not aware of any outboard that is of appropriate size for an M15 that has an alternator. Alternators usually found as option for motors 5HP or greater. Some 4HP motors have identical powerhead (aka block) as a 5 and 6 HP so an alternator can be added by the owner.
Also, the alternator doesn't start putting out any significant power until the motor is turning higher RPMs ... meaning the M15 is being overpowered (trying to climb the bow wave and dragging the transom deep in the water.
A M15 has absolutely no need for a motor greater than a Honda 2/2.3hp. larger motors are bad for boat trim, aka sailing ability, because of excessive weight hanging aft of the transom.
:: Dave Scobie :: M6'8" #650 :: Baba 30 #233 DEJA VU :: SV SWALLOW - sv-swallow.com :: former owner M17 #375 SWEET PEA - m17-375.com :: former owner M15 #288 SCRED - m15namedscred.wordpress.com <<-- new site!
On Thu, Nov 4, 2021, 11:32 PM Jim Sadler <jimsadler@jascopacific.com> wrote:
Looking for small OB that will power my tiller pilot Capt Jim M15
Get Outlook for iOS<https://aka.ms/o0ukef>
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com