I have no experience with thrusters/trolling motors/electric outboards so looking for advice.
Goals:
2x motors for redundancy & differential steering. Reliability is #1 priority I don’t want to be stranded.
Limp at 2mph on single thruster in case one system dies.
Cruising target speed 4mph+
10 Mile Range
Lightweight as possible, I’ll be traveling on this dual sport motorcylce, going offroad so weight is critical
Dual Sport Motorcycle Info.
550lb Gross Weight including rider and luggage
6’ x 18" Pontoons (blunt face cylinders I bought to test the frame, I’ll eventually replace with pointed shaped pontoons to reduce drag, same size cylinder but 1’ added to the front)
They currently draft 6" of water
Dirtbike Wheels are submerged to their axles
bottom 4" of the engine/frame cradle are submerged, front of this section has a 45 degree aluminum skidplate reducing drag
entire section is 10" wide x 15" long
I’d to use a pair of T500 or Bixpy K-1 as they’re so lightweight, the K-1 especially has very low current for the claimed thrust, which in theory would let me take lighter lipo batteries.
My concerns:
My vessel is HIGH DRAG
Small prop diameter, high prop rpm, will just slip/cavitate and not propel my vessel.
The suggested 1 minute runtime limit (for temps) at 24v listed for the T500…
I’d really like to avoid using chopped trolling/outboard/pod if possible to say weight. I don’t want to buy smaller thrusters only to find out I need 9"+ propellers and low kv motors to make this work.
Having never handled ANY thrusters, I just don’t know what to expect from them.
Hi @thelastfoiter
Welcome to the forums!
That is certainly a unique project - an amphibious motorcycle!
Is there any reason you couldn’t power the thrusters you select with the motorcycles stator, or is it not rated to produce much electrical power?
Your high drag vessel is well suited to thrusters - they are designed to go slow, and push hard while doing so (tractor.) The M200/M500 with weedless prop are designed to go fast with great efficiency (sports car.) With that said, I would not expect a pair of thrusters to give you more than 2-3 mph, max!
It’s impossible to predict range without knowing how much power the system draws, at what speed, with what battery/ electrical power capacity onboard. Once you do some testing that should become clear!
If a single thruster goes out, you’re no longer going to be able to drive in a straight line (assuming thrusters are fixed, and mounted on pontoons.) If you mount them together on a tiller, then you could still “limp” with only one, but your speed will be reduced by at least 50% - 1mph? Going to 4x motors would give redundancy and potentially higher speed!
The proprietary Bixpy K-1seems like a good fit, but you’d be locked into using their battery, and may find repair of the thruster not possible to accomplish yourself.
Best of luck on your project! Are you trying to accomplish a particular route that requires traveling via water??
I’m mostly getting scared away from thrusters by rudimentary AI drag estimates.
Responding in order:
Stator is wimpy, its a street legal dirtbike basically. ~150w (max) to spare
I’m seeing most trolling/e-outboards make their thrust at 1000-1500rpm but the thrusters are making their thrust at roughly double that.
Point taken on range, just wanted to throw out my goal because I want to stay light and not carry 40lbs of batteries.
I suspect I can correct steering with the front wheel + tiny carbon paddle if need be.
4x motors is an interesting idea… however these are already expensive for me and another $1000+ is just too much.
K-1 can use any 22v-30v power source with the K-module, AI says their ultra high rpm would make them a poor fit for 3rd party VESC, I don’t know how true that is. (Looking at Trampa tier)
No particular route, I want to be able to island hop, and really explore wherever I want to go.
