9.8 tohatsu

[hipster dufus]

i will keep this simple. 9.8 4 stroke tohatsu,2009,1444 g3 jon. 19+ mph with 1 person@ 5400 rpm. 2 people approx 10 mph,@4500 rpm. these are the max speeds i get with the best conditions, measured by gps. will a prop change increase my top end with 2 people and if so what prop? it has the stock prop on it now. i do the majority of my fishing with 2 people and would like to top out @ 10 mph or better. thank u for ur opinions and help

 

[steelespike]

Re: 9.8 tohatsu

What is the maximum rated rpm?We need the prop size;usually on the barrel or under the prop nut.If the Jon is basic and light and you are under 200 lbs I would think it might get close to 21mph. alone.and with another 200 lb er 15-18.
Your antivent plate(just above the prop should be about even with the bottom of the boat perhaps even higher.raise the motor to a point just before venting becomes a problem. Just use some flat sticks on top of the transom to support the motor while you tighten the clamps. In ideal conditions you might gain a mph or 2.
Could be the difference getting over the hump out of the hole.

 

[hipster dufus]

Re: 9.8 tohatsu

stock prop is an 8.5 x 9. went out today. 4400 rpm with 2 guys and gear. 5350 rpm with 1 guy. 9.2 vs 17.2 mph. boat was a little heavier today. will a prop change get my rpm at wot with 2 guys up to 5400-6000 rpm?if so what size is recommended? maybe im chasing after nothing. i mean what can i really expect out of a 9.8. i would like to make sure im not damaging my engine. i probably should have got the 20hp, but i thought i would be fishing restricted waters more. i know i should have got the electric start. thank u all

 

[steelespike]

Re: 9.8 tohatsu

Your 2 guy rpm is not statisrically valuable because I don't think youre getting over the hump and truely on plane.
Did you check the motor height? Could mean up to 2 mph if its really low now.
carefull trim setting and weight distribution as well.Gastank placed midway forward instead of at the stern.Eliminate as much weight as possible; 3 gallon tank, motor will run over 3 hours at wot on 3 gallons.Use a light weight danforth style anchor.A few pounds and their placement could make the difference getting over the hump.
Assuming you max rpm is 6,000 It does appear you need to go to a 8" prop.
Should put you close to 6,000 with one aboard.
Believe it or not a bare bones 48 or 54" jon will most likely plane easier than a 44 with 2 aboard.