Extra emulsifier holes= more mpg?

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Extra emulsifier holes= more mpg?

shinyribs
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 I read last night about a guy who drills extra holes in his emulsifier tubes. He double the amount of holes it has originally. The idea is that it foams up the fuel much more than before,making it easier to vaporize and therefore better fuel mileage. He is claiming 60 mpg on a CB550,which was a 10+ mpg over stock emulsifiers.

Anyone have any experience concerning this? If there was even a 2-3 mpg increase i would drill mine,just wondering if there is any truth to it,or a negative consequence side to it?
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Re: Extra emulsifier holes= more mpg?

pat english
id like to know what an emulsifire is..also about this mod..
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Re: Extra emulsifier holes= more mpg?

shinyribs
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You know the tube above the main jets with the holes in it? Thats the emulsifier tube. When fuel is drawn out of the fuel bowl thru this tube the holes cause the fuel to bubble,or emulsify,making it easier to atomize. The more fuel is atomized,or the smaller the droplets,the more complete it is able to burn. It makes sense that extremely atomized fuel would burn more complete,thus you get more bang for your droplet,so to speak.
It's the same reason that these new turbo diesel trucks run insane fuel pressures-25,000+psi.It's all about taking the fuel from a liquid and trying to turn it into a vapor,more or less.

I can't think of any reason extra holes would not help in the emulsifying of the fuel,but it seems Honda woulda done it if an extra 10 mpg was that easy to get.
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Re: Extra emulsifier holes= more mpg?

pat english
ah ok..you should just do it and do a road test..let us know
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Re: Extra emulsifier holes= more mpg?

shinyribs
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Sure. I'll be the guinea pig,but if my bike runs like poo,you have to supply new bubble tubes





...got tired of typing emulsi...whatever
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Re: Extra emulsifier holes= more mpg?

pat english
lol..sorry i dont have any..
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Re: Extra emulsifier holes= more mpg?

Re-run
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In reply to this post by shinyribs
I know  guy who did that. His name was mark(hondaman) on the "other"  sohc forum.
What he did, if I remember, was to ENLARGE the holes. I don't recall him adding any but making some of them bigger. The idea was for better mid range response. I don't recall if it helped on mpg or not.
The ride IS the adventure. The destination is just to get gas!
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Re: Extra emulsifier holes= more mpg?

pat english
In reply to this post by shinyribs
that would be cool if you could find that hondaman thread....

hey bro,did you want that shift fork thingy?..im boxing up youre shit right now.
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Re: Extra emulsifier holes= more mpg?

shinyribs
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Pat,Yes I do. Just make sure you dont get rid of your only good one.   I need a bill,too.  Thanks
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Re: Extra emulsifier holes= more mpg?

shinyribs
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In reply to this post by Re-run
Rerun, I havent seen that part of it discussed. What I was reading was a guy with a CB550 that did it for fuel mileage alone. He drilled matching the original size holes,he just added more of them.He doubled them,I believe. He didnt report on any power increase in any particular ranges.  I'll see what else i can find,but I knew we had some guys who used to hang out 'over there' and figured they might have some insight.
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Re: Extra emulsifier holes= more mpg?

Re-run
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In reply to this post by pat english
here is what I have so far. Seems to be mainly on the earlier K bikes but might be something to experiment with.
In the late CB750K3 Keihin carbs, Honda added a "lifter" to the needle jet to improve fuel atomization in the 3500 RPM range and reduce the tendency these engines had of fouling the plugs in city driving. However, these items don't fit the earlier carbs, but there is a fix for them, too: remove the "emulsifier tube", also known as the "main jet holder", and you will see tiny holes cross-drilled in the part where it screws into the carb body. These holes range in size from .025" in the "K" model to .033" in the "K1" to .035" in the "K2" and early "K3" setups.

Drill half these emulsifier holes out to .040" and reinstall, driving it a while to see the improvement. If it's not enough, drill the rest out, too. If you live at altitude, like me (Denver, CO), drill ALL of them out to .040" to start, and consider drilling at least 2 EXTRA .025" holes as well. I finally drilled the original ones to .044" and added the 2 extra .025" above that.

I will dig a bit more but I think that was it on the subject.
The ride IS the adventure. The destination is just to get gas!
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Re: Extra emulsifier holes= more mpg?

Re-run
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In reply to this post by shinyribs
I used to hang out over there but didn't care much about the baby 4s.
The ride IS the adventure. The destination is just to get gas!
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Re: Extra emulsifier holes= more mpg?

TOOLS1
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In reply to this post by shinyribs
Hey, just start drilling random holes until you come to your senses.
TOOLS
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Re: Extra emulsifier holes= more mpg?

Re-run
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In reply to this post by Re-run
I found this and I think this is what is being looked for.

http://www.sohc4.net/index.php/increasinggasmileage-cb550/
I don't think it requires login in. if it does, I will copy/paste.
The ride IS the adventure. The destination is just to get gas!
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Re: Extra emulsifier holes= more mpg?

shinyribs
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I linked to it without logging in,so it's all good there. That is exactly what I was reading. That's a huge mileage increase. Too good to be true?
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Re: Extra emulsifier holes= more mpg?

Re-run
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Hard to say. It is possible but I suppose it depends on any other possible mods that have been done.
The ride IS the adventure. The destination is just to get gas!