Hi Simon,
Some more precise information would be very helpful . . . .
🤔
Beste Grüsse Michel-C.

The motors power a partly refurbished Veron Vosper high speed patrol boat which was originally designed to be powered by a 10cc Ic engine. I saw one running many years ago as a youngster and wanted to replicate this performance. I decided that there would be no half measures as the hull is 52" and made of ply. I did not want to have to up engine the boat as a result of disappointing performance, hence the 24v via 20 3700 amp hr Nimh cells Per motot. The performance is excellent even with one 900 motor down.
Regards
Kevin

The motors have 4 threaded holes in the front face of the motor casing. I happily run mine on 14.8v and are quite happy to drive a 50mm diameter 4 blade prop for about an hour before the batteries need changing. The motors are hardly warm, so additional cooling is not really necessary in my own situation.

But why would you need to run 24volts? Thats a lot of voltage/battery weight. is this a necessity?
Why cant you run at a lower battery voltage and also save on battery weight too.

Thanks.
Do the motors you're using accept. 24V? I would also be interested in how they are fastened. The Graupners have four lugs to bolt onto the motor. Bracket/frame. Also do yours have integral cooling fans or are they cooled by water or is cooling not necessary.

Regards
Kevin.

Do you really wanna pay "graupner" price for a motor?

theres a guy on ebay selling "900 size" motors of equivalent rating for a mere £13 !

Ive run a pair of these in my Mersey Lifeboat and have no problems since fitting them over 18months ago.