9.9 vs 10 hp?

[Studman]

Does anyone know why outboards are 9.9 hp vs 10?
My buddy says it's because you need to be over 16 to operate anything over 10 hp but I disagree
Anyone?.

 

[mwph]

State to state obviously but....Does a "vessel" with 10 HP require a registration?

 

[2texoma]

Many rules such as age as you mentioned,HP not to exceed on some small rivers and reservoirs,registeration and such say 10HP. Mfgrs say 9.9 just so the owner doesn't have some official confuse the issue. At least on past OMC products,parts for 9.9 and 15 are identical except carb.

 

[PostTime]

It seems like I heard that it was because of the "under 10 hp" limit on so many small lakes. OMC with the 9.5 hp squatty engines in the late 60's to mid 70's when they came out with the 9.9 hp. Merc had the 9.8 hp in that time frame too. Back in those days there was no such thing as a minimum age limit for operators. I remember running a 4hp Evinrude on a 9 foot Starcraft jonboat at age 10 or so. I would lean forward, just barely able to reach the tiller so that the boat would plane off! Probably going under 10 mph but boy was it fun!

 

[SeaRide]

I remember asking this question in the late 70s when i had a 4 hp johnson on a 11'6" jon boat. I don't think it was a registration issue as LA reuqired my boat to be registered. I vaguely remember the reason being related to the military and active duty personnel being able to store engines on base with less than 10 hp. In more recent times, i have seen bases with dedicated rv/boat storage and the boats had more than 10 hp. The lake resriction post also makes sense. BTW, PostTime, i bought additional fuel line for my 4 horse so i could move the 3 gallon fuel tank ahead of the second seat. I could plane quicker and at lower speeds.

 

[moparlvr4406]

in Indiana it is 10HP limit on some small waters
but that doesn't mean a 15hp carb wont fit under that sticker on the cowl :wink:

 

[ch435]

The boundary waters canoe area up in northern Minnesota, southern Canada is a huge area with mostly no motors allowed, but when they are, they must be under 10 hp.

 

[blaster]

That's not so easy to do nowadays with the 4 strokes. I have a friend who has a 9.9 without the restrictor plate and its really a 15. We go to a HP restricted impoundment and he is always faster than me. Maybe I should turn him in.

in Indiana it is 10HP limit on some small waters
but that doesn't mean a 15hp carb wont fit under that sticker on the cowl :wink:

 

[Toecutter]

In Canada, a pleasurecraft must be registered (and display the reg #s) if it has an engine size of 10hp or more. I had always understood that manufacturers 'created' the 9.9 class to offer the largest possible horsepower in an unregistered engine.