Piper Boat Owners Club Forum

Welcome to the Piper Boat Owners club Forum. The Forum for owners of Piper built Narrowboats and Barges and anyone interested in Piper Boats. The owners club is completely separate from Piper Boats. Please feel free to post a message to club members and web site readers.

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Is my boat over-propped?

Hi my boat is 37 foot, cruiser strern, approx 10 tonne. Beta 28hp engine, 2009, name Nutcracker II a genuine piper boat as I have checked with Piper staff who were very helpful. The prop is 16x9 as stated in oringinal owners handbook. Upto say 1100 revs boat responds well and speed increases as revs increase. At about 1109 revs its doing 2.9 mph. If I try to go above 1100 revs the speed does not increase much at all and engine sounds as though it doing much more work. I have checked with beta and they say prop for this boat may be better suited to a 15x8 or 15x9. Is it possible for Dot to read this and ask David what he thinks please. Thank you John

Re: Is my boat over-propped?

What was the depth of water where you conducted your 'speed trial'. It is quite possible that the increase in revs may have resulted in 'dragging' the stern deeper in the water and therefore friction between the bottom of the boat and the canal bed could have come into play.

Re: Is my boat over-propped?


David says how many revs do you get when you open up the engine fully, in gear?