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Old 01 July 2012, 17:38   #1
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How the right Prop can transform your rig

Just got back from testing Pigs Ear with her new prop.

When we got this Osprey 7.0 the Honda 225 was spinning a Laser II 21".

After some teething problems following a shockingly shite service from Tony Hole in Plymouth we got things back on track and fuel usage and performance seemed OK. However having read up some reviews of tests on the Honda 225 it was decided to try out a different prop.

The articles on the net suggested the big Hondas like a bigger diameter prop as the gearcase is quite chunky so the extra diameter helps the prop get into clear water. After speaking to Propeller solutions we decided to give the Mercury Mirage II a go and drop a couple of inches in pitch to 19" as the laser was holding the RPMs at about 5400 where the Honda should be up in the 5800 to 6000 RPM range at WOT trimed out.

Having taken her for a spin today we were absolutely gobsmacked at the difference this prop has made.

- Top speed was at 42 knots, now at 46
- Hole shot improved massively.
- RPMs are spot on at 5800
- The hull does not fall onto the left chine as it did tend to do previously.
- Fuel usuage at anything from 25-35 knots is less than 1 litre per nautical mile.
- The whole atitude of the boat has changed and now runs much flatter so giving a much smoother ride.

The performance was stunning. When you hit the throttle she literally leapt out of the water.

Just goes to show how much the wrong prop can make a boat just not feel dialed in, however when you get it right it makes a good boat just so much better.
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Old 01 July 2012, 17:59   #2
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Good result Chris, it's great when it works out. I went through a similar process with BP. The engines came fitted with BRP vipers, which were ok-ish, but the boat felt wishy washy & flighty. I swapped for Mercury Rev4s & the difference was remarkable, a different boat. A good dealer, willing to work with you is a godsend, I was lucky to have Mike Vincent at South Coast Marine on my side. He made suggestions & was willing to loan me props to try.
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Old 02 July 2012, 04:45   #3
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Nice one Chris, my osprey has a tendency to drop onto the left chime too, as did my last one..., I've been advised to try a 4 blade prop... After reading this I think I'll give it a go....
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