thefullmonte
New member
I do like the idea of the oil mixing with the fuel first. I just wish it happened at the fuel inlet to the carb and not before the fuel pump. I'm thinking I might try a Y connector at the inlet on my long track. That would probably be the best of both worlds. Lol
opsled
Active member
The oil is entered prior to pump to help get it mixed. Before the pump is better than after.
The oil injection system is variable to keep up with RPM and load (trottle position) so as to always keep a consistant oil/fuel ratio in the carbs no matter what you are doing with your thumb. The system needs to match fuel use rate to keep the fuel/oil ratio down stream from entry equal at all times. Direct injection systems do the same thing. The difference is that a direct system does a poorer job of mixing.
Oil injection systems are not designed to provide a different ratio under different conditions. This is the misconception.
Leave it stock and you will never have an issue.
opsled
The oil injection system is variable to keep up with RPM and load (trottle position) so as to always keep a consistant oil/fuel ratio in the carbs no matter what you are doing with your thumb. The system needs to match fuel use rate to keep the fuel/oil ratio down stream from entry equal at all times. Direct injection systems do the same thing. The difference is that a direct system does a poorer job of mixing.
Oil injection systems are not designed to provide a different ratio under different conditions. This is the misconception.
Leave it stock and you will never have an issue.
opsled
toydoc
Member
I have done both. Stock is fine. But even Yamaha can't make up it's mind what is better. Yamaha out boards and PWC are direct, they even brag in the adds how direct is better
I just like the direct, stock is fine too. I've just never had a stock sled for more than an hour, and a half. That's how long it takes to get it home from the dealer to start ripping it apart. I love to pre-buy parts. Pistons, and cylinders always look great. Everyone's different.
Throttle Junkie35
New member
The old di question, I am a fan of the direct injection. I believe as far as a/f mixture is concerned, it is the viscosity of your fuel mixed with oil that would be part of the equasion also. As gas/oil mixture does not flow as freely through carb/jets as gas alone does. No need to worry, just need to jet accordingly. just my .02 cents.
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