Old boat upgrade

[Spat]

Converted my old Systems cat to brushless and lipos
Leopard 3674, 1900kv, 4s, 39mm prop, 150 flex shaft and original steerable strut. Flex is 8 3/8" long, stuffing tube 1 3/4" original to boat, liner is only 2" long.
Everything looks nice n straight, but keep burning up the liners. Was thinking about the strut causing too much binding in the corners?
Any thoughts would be a great help.
Thanks Dom

[Fluid]

What are you using for a lube on the flex cable? How is the liner secured to the stuffing tube?


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[Spat]

Marine grease from OSE and the liner is a very tight fit in the tube.

[Fluid]

Your setup is good for that size boat, but it is well beyond the original design rpm. I suspect that your analysis is correct. I haven’t played with a Systems cat in over 20 years, and I eventually changed to a standard strut and separate rudder. If the liner wear is too much for you, consider locking the strut and using a separate rudder. IME the steerable strut enhances the boat’s tendency to hook and spin out in the corners.


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[Spat]

Thanks, do you remember whose strut you sed?

[Spat]

Used

[Fluid]

It was an Octura sized for the cable. I used 1/8” cable back then, 0.150” is more suitable with modern power. Today I’d use Speedmaster but that’s just me.



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[Spat]

I was looking at that and also another one that could be purchased with a new shaft, tube, liner, think it was TFL. Trying to keep it simple. Thought this was going to be an "easy" upgrade, motor, speed control, and away we go! Not! Started out, burnt up nicads, understandable, got lipos, runs great and then the whipping started. Only inside the boat burnt up a motor because of it. If I get this figured out I might try a scratch build for sport running. Thanks slot for your input Fluid