Drain the carbies

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Freddy
Posts: 695
Joined: 06 Sep 2017, 11:06
Location: Sydney Australia

Re: Drain the carbies

Post by Freddy »

Slight digression, regarding ethanol. As I said in a previous post I immediately noticed the drop in performance the one time I stuck E10 in the bike. Now why would that be?

How about the 750's are jetted lean to start with, at least for sea level, moderate humidity and temperature. Stick in E10 which will make the bike even leaner (reason: ethanol contains oxygen atoms and straight gasoline doesn't) and performance suffers.

I got a significant performance improvement for no significant noticeable increase in fuel consumption on my D1 by going up two main jet sizes on the outer carbies, and one jet size on the inner two carbies, making the 4 carbies now all the same size main jet. This was for straight 91 RON gasoline, widely available in Australia (but with a 'green' Government tipped to take office in a few days how long ethanol free gas will be available is anyone guess). If I had no option than to run fuel with ethanol then it would be an even more compelling case to install larger main jets.

The reason fuel consumption hasn't significantly increased is because I'm still running the original pilot jets, needles, and needle jets. These are doing all the work just cruising around, or at constant highway speed. It's only when you gas it hard that the main jets come into play.
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