Scenario: A 55 lb. trolling motor is mounted on the rear of an aluminum Bass Tracker. A 30 lb. motor is mounted on the front.

Question: Would speed increase, decrease, or remain the same if the big motor was mounted in the front and the small motor in the rear?

No scientific proof but I think it would stay the same.

That's what I am thinking as well.  I didn't know if going from push to pull would have any effect.

We are trying to get a little mote speed for a tourney on Sat. so we can get to the honey hole.

Guess I shouldn't ahve dropped physics in college!

Yea I'm thinking it wouldn't matter. Your dealing with the same prop pitch in both directions, as well as a DC motor that's equally efficient going in both directions.

Now here's a question for you tho, if you have the big motor on and then add the little one being of a lower thrust value would the small one have a positive or negative effect on drag?

Bill

Now you've gone and made me think even more...how am I gonna sleep tonight?   :-?

We have been running both at the same time.  The front (smaller) will steer while the big one is on.  

It seems like we go a bit faster with both, however.

I'll have to get a cop buddy to come up and run radar on us.  

All you need is a stop watch and two set points. Get up to speed and as you pass one point start the stop watch, as you pas the second point stop the watch. Repeat in the same direction with different motor configuration. Lower time wins.

Bill

check your gps speed!

Yea or that.....

Scenario: A 55 lb. trolling motor is mounted on the rear of an aluminum Bass Tracker. A 30 lb. motor is mounted on the front.

Question: Would speed increase, decrease, or remain the same if the big motor was mounted in the front and the small motor in the rear?

I just had this conversation with a guy who fishes with us..

he is an engineer and seems to overthink everything.

he says...the two trolling motor thing is silly. The 55lbs thrust motor is already pushing the boat faster that the 30 lbs so you are negating most of the thrust of the 30 lbs motor. adding the 55lbs motor to the 30 lbs motor does not make it 85lbs of thrust...more like 60 or 65 lbs of thrust at the most because the 55 lbs motor is already pushing the boat faster than the 30 lbs motor can catch new water to push the boat.

I do not know about that...

I think though that your speed would be about the same.

Like the physics guy said "both in should give you 60# ish."   That's still better than 55#.

As for witch one in front or rear I don't think it would make nearly as much difference as having good fresh batteries and weight distribution.  You want that boat pretty close to level.  

gps or two points and a stop watch is the only real way to test it.

Scenario:  A 55 lb. trolling motor is mounted on the rear of an aluminum Bass Tracker.  A 30 lb. motor is mounted on the front.

Question:  Would speed increase, decrease, or remain the same if the big motor was mounted in the front and the small motor in the rear?

I just had this conversation with a guy who fishes with us..

he is an engineer and seems to overthink everything.

he says...the two trolling motor thing is silly. The 55lbs thrust motor is already pushing the boat faster that the 30 lbs so you are negating most of the thrust of the 30 lbs motor. adding the 55lbs motor to the 30 lbs motor does not make it 85lbs of thrust...more like 60 or 65 lbs of thrust at the most because the 55 lbs motor is already pushing the boat faster than the 30 lbs motor can catch new water to push the boat.

I do not know about that...

I think though that your speed would be about the same.

I just tried out my 40lb bow mount with a 28lb stern mount and there is a very noticable difference from when either one is turned off.  It feels like the difference between walking and power walking.  It took me less than 10 minutes to get to a spot I fish, when it normally takes 15 minutes with the stern drive.

Thanks for the input.  It "feels" like the boat goes slightly faster with both motors on.  We didn't get around to moving motor placement.

Having never tried this nor taken any physics classes. My thoughts would be that with the added 30lb thrust TM and added battery weight that in fact you may go slower. The 30lb thrust TM isnt as fast as the 55lb thrust so it might have an effect of slowing you down just adding more all around drag to your boat. Just my thoughts... A GPS reading would easily put this to bed though.

I just had this conversation with a guy who fishes with us..

he is an engineer and seems to overthink everything.

he says...the two trolling motor thing is silly. The 55lbs thrust motor is already pushing the boat faster that the 30 lbs so you are negating most of the thrust of the 30 lbs motor. adding the 55lbs motor to the 30 lbs motor does not make it 85lbs of thrust...more like 60 or 65 lbs of thrust at the most because the 55 lbs motor is already pushing the boat faster than the 30 lbs motor can catch new water to push the boat.

I do not know about that...

I think though that your speed would be about the same.

Your engineer buddy has really over-thought this one. There's no way that 55lb motor will pull that, or any, boat fast enough to negate the thrust from the smaller motor. If you want to prove that just lift the small motor out of the water while the front motor is running full tilt. Turn the small motor on high. When you drop it in the water you'll notice it slow down. It's slowing down because it is being loaded. You'll notice the boat speed up, and that will be the end of that argument.

I'd leave the bigger motor on the front. It's a lot easier to fight the wind by going into it, and the bigger motor will be better for that.

Cheers,

GK

I'd leave the bigger motor on the front. It's a lot easier to fight the wind by going into it, and the bigger motor will be better for that.

Cheers,

GK

Didn't consider that.  It has typically been windy on that water and we use the big motor to get us places and the smaller motor to manuever us once we are there.  We actually drained the battery on the small motor this weekend due to the wind.  

Is it same to assume that the more powerful motor will suck battery power quicker that the smaller motor is both are used in the same time and fashion (i.e. one hour of run time on the big motor will use up more power than one hour on the small motor)?

Its time to figure out the strategery for next year!

I'd leave the bigger motor on the front. It's a lot easier to fight the wind by going into it, and the bigger motor will be better for that.

Cheers,

GK

Didn't consider that. It has typically been windy on that water and we use the big motor to get us places and the smaller motor to manuever us once we are there. We actually drained the battery on the small motor this weekend due to the wind.

Is it same to assume that the more powerful motor will suck battery power quicker that the smaller motor is both are used in the same time and fashion (i.e. one hour of run time on the big motor will use up more power than one hour on the small motor)?

Its time to figure out the strategery for next year!

Yeah, strategy will be a 24v system if I can afford it.