motor rating
upnortdave
Posted 9/27/2015 7:40 AM (#786141)
Subject: motor rating




Posts: 670


Location: mercer wi
I don't understand. Was lookin at esox mag and the rating for the tiller was 60hp and the rating for counsel was 135hp. I've seen that with all tiller to counsel. It's the same hull and transom. Just wondering why the difference. Who has the answer.
Pointerpride102
Posted 9/27/2015 8:58 AM (#786149 - in reply to #786141)
Subject: Re: motor rating





Posts: 16632


Location: The desert
Steering.
sworrall
Posted 9/27/2015 9:02 AM (#786150 - in reply to #786141)
Subject: Re: motor rating





Posts: 32935


Location: Rhinelander, Wisconsin
The US Coast Guard. Horsepower ratings are set by a formula (length, beam, exact height of the transom where water enters first, etc) and a set of performance tests the boat must pass. Usually, the tiller rating will be less than half the console rating. I spoke with them several times about power tiller steering and possible tiller HP changes, and Po Chang, the guy in charge, assusred me those would not change due to two main factors:
1) Tiller steering can be and is much more 'abrupt', creating top speed turn test failure with a big motor
2) The seating in a tiller creates problems with seeing around passengers, so the USCG wants tiller boats under their control to rate (boats under 20') lower and run slower to decrease the possibility of accidents.

Here's a backyard boat builder synopsis:

http://www.boatinghowto.com/downloads/info/backyardboatbuilders.pdf

Pepper
Posted 9/27/2015 9:53 AM (#786158 - in reply to #786141)
Subject: Re: motor rating




Posts: 1516


Thanks for the explanation. Makes sense and explains why you can get a 175 hp on tiller over 20 ft but limited to 90hp on 18ft boats
upnortdave
Posted 9/27/2015 11:52 AM (#786167 - in reply to #786141)
Subject: RE: motor rating




Posts: 670


Location: mercer wi
Got it. Figured it had to do with something with high speed control.
North of 8
Posted 9/28/2015 11:32 AM (#786332 - in reply to #786167)
Subject: RE: motor rating




I recently bought a used 18' Pro V tiller, with the motor being a 90hp, the max for the boat. In a console model the max is 150.

I was cautious as I got acclimated to the tiller and it does turn much quicker than a console and you have to factor that in. With even more horsepower, I think even small handling mistakes could result in real problems.