1996 Yamaha C25hp bogging

[99yam40]

took me close to a year to finally figure out a previous owner drilled all 3 main jets on my C40. It ran best with the cowling and silencer off and running into the wind, if I turned and ran with the wind the high speed miss came back.

Glad you found your problem quickly

[Donman89]

Ya quite a bit less smoke. The first run in a lake the thing was really rich that it left black smears on the back of my boat. Man that would be crazy to be running fine into the wind and run good and go with the wind and run like crap. Idk if I would have figured that out lol. If this didn't fix the problem i don't know what else I could have done to fix it. I was gonna buy a new coil and electrical after that. I don't see why anyone would drill out the jets of an outboard unless you are doing motorwork and adding performance.

[99yam40]

some people think just adding fuel will increase HP in motors and screw up more things then they think they do.
some think they did a good job and swear they got more HP

[TownsendsFJR1300]

I have, in older carbed motorcycles, replaced idle jets (a step richer).

A Honda 1100 V twin I owned, from the factory, was adjusted so lean, it had a bad (and very annoying) hesitation right off idle. The richer jet solved the hesitation. A lot of bikes in the mid 1980's were like that..

My current Snapper lawn mower(self propelled) ran rich brand new, black plug, black smoke on start up (with no primer push). I ordered and bought one step leaner main jet, now it runs like it should. Its about 10 years old, a HD version, but back then, the emmision folks were pretty stringent. How this one got by, I don't know..