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Converting 99 to 15 hp

"Steve, I have a 9.9 4 stroke,

"Steve, I have a 9.9 4 stroke, 2000 and the engine is really a 15 horse. It is limited by a threaded bolt to allow only enough rpm to produce 9.9 horse power. I can get 15 horses by adujusting the bolt. This should be done with a rpm gage attached and under a load. Pat Muckelroy"
 
Steve i have a 9.9 2001 and i

Steve i have a 9.9 2001 and i converted it by removing the bolt pat mentioned and also replacing the carburater. TThe throat of the carb is bigger on the 15 than on the 9.9. These are the only two things different according to my Honda guru.
Rich
 
Update.

Guys I found a grea

Update.

Guys I found a great deal on low hour 15 h.p. and purchased it. Thanks for your help though.

Steve
 
Thread Hijack:

I have a mid

Thread Hijack:

I have a mid 80's BF100 9.9hp that I need to rebuild (broken ring). Any thoughts on converting it to a 15hp while I'm at it? I've been told it's just a larger jet and warmer thermostat? Could it really be that easy?
 
The 9.9/15 HP are completely d

The 9.9/15 HP are completely different (and larger) engines than the BF75/BF100 ("7.5 HP / 10 HP") which are now sold as 8 HP's (BF8).
 
"Thanks for the info Art. I tr

"Thanks for the info Art. I tracked down some parts lists/numbers for the 15hp and you're right - Completely different engines. Oh well, guess I will stick with 10hp!"
 
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