Electric outboard for 2.8m SIB

[lightning]

l am going to buy an electric outboard for my 2.8m Zodiac

l think it will be ideal for the canal or Broads where quiet running is an obvious advantage and the speed limit is only 4/5mph anyhow.

There is some tidal effect on the broads in places, though it doesn't seem to be very much.

l've looked at these outboards and they start at £150
l think the cheap one will be fine, the reviews are good and it won't get heavy use.

My question is, how much power do l need? The £150 one was 30Nm and for another £100 l could have 45Nm
lf l pushed the, erm, boat out and spent £360 then 60Nm would be under my command.
l
What kind of speeds will these achieve? l only need around 5mph maximum with possibly a bit in reserve if l need to run against a bit of tidal flow on the Broads.

Also l will need a battery obviously and these now seem to be a lot lighter now that you can get the lithium ones.

I take it that a bigger engine will run the battery down faster, l would hope to get maybe three hours running from a single battery charge.

ls this achievable?

[lightning]

Anybody used one of these motors and can advise me?

[Limecc]

Originally Posted by lightning

l am going to buy an electric outboard for my 2.8m Zodiac

l think it will be ideal for the canal or Broads where quiet running is an obvious advantage and the speed limit is only 4/5mph anyhow.

There is some tidal effect on the broads in places, though it doesn't seem to be very much.

l've looked at these outboards and they start at £150
l think the cheap one will be fine, the reviews are good and it won't get heavy use.

My question is, how much power do l need? The £150 one was 30Nm and for another £100 l could have 45Nm
lf l pushed the, erm, boat out and spent £360 then 60Nm would be under my command.
l
What kind of speeds will these achieve? l only need around 5mph maximum with possibly a bit in reserve if l need to run against a bit of tidal flow on the Broads.

Also l will need a battery obviously and these now seem to be a lot lighter now that you can get the lithium ones.

I take it that a bigger engine will run the battery down faster, l would hope to get maybe three hours running from a single battery charge.

ls this achievable?

I think it could work well on the Broads. We hired an electric boat and had a lovely day out from Wroxham. Followed an otter for ages on a quiet section.

I'd carry a spare battery like I carry a spare fuel tank though.

Good info on this thread regarding power output if you've not read it or similar already:
Electric Auxiliary?

Regardless of outboard, canals are bad places for soft-bottomed SIBs. Too much jagged debris lurking beneath the surface and on our first and last canal excursion a plastic bag tangled the prop and the tubes picked up a lot of oil and dirt that took a lot of shifting afterward.

[babbot1]

Is it a trolling motor or an outboard like torqeedo?

I use a 55lb(I think that's 75nm) minn kota trolling motor on my 2.9 sib. At full it moves fairly well. I would say hull speed. I never used a gps but probably 4-5 mph. It's plenty to get me here and there across our river.

I would go as big as budget allows. You don't have to use 100% throttle but that reserve is always there. I usually run about 1/3-1/2 throttle to putter around, its about rowing speed.

It uses about 50amps full throttle but it drops off significantly when you back off. You can get estimates to size your battery. There may be some charts to give you the exact amps at each throttle position. Torqeedos are different animals. More expensive but they can get you on plane if big enough.

[Bern Hanreck]

Originally Posted by lightning

There is some tidal effect on the broads in places, though it doesn't seem to be very much.

We are not talking Bay of Biscay , Bermuda Triangle or Corryvreckan Standing Waves but be a bit careful where the Broads meet the sea....ie Breydon Water near Great Yarmouth ......

https://www.broads-authority.gov.uk/...great-yarmouth

[lightning]

The ones l was looking at were Minn Kota trolling motors.

l was hoping to get away with the £150 one, if it will do 4mph that will be fine.

Also l got the units wrong, thrust is in lbs not Nm !!

[babbot1]

The 45lbs should be good and the 60lb would probably be a waste of money, IMHO. I would think the 45lb is pretty close to the performance of my 55lb.
Not sure about the 30lb. It may be disappointing.

If you go to Minn Kota's site it has a sizing chart but they seem very optimistic. Maybe they assume flat calm and a gale force wind at your back. :-)

[babbot1]

One more thing, usually you can lock the motor in place. I like to lock it in place going straight at about 1/3 throttle then row. You can move quite well and steer with the oars and not have to row hard. Just something to consider if you do go with the smaller motor.