Always rich/I hate carbs

[skids]

Blast 'em with carb spray right through the spray tube into the jet. It will drain into the emulsion tube and down through the main jets. Then blow air through them to make sure they dry out clear.

Originally posted by Snow
How would I make sure the main air jets are all clear? Do I need to get a special carb cleaning wire kit?

[skids]

I forgot to tell you, it is a good thing to remove the pilot jets when you do that with the 78/79 carbs, in case particles also wash into the pilot jet area through the interconnecting borehole.

Originally posted by skids
Blast 'em with carb spray right through the spray tube into the jet. It will drain into the emulsion tube and down through the main jets. Then blow air through them to make sure they dry out clear.

[Snow]

gotcha, will be pulling the carbs and doing that tonight - thanks for the advice

[Ken Talbot]

Don't forget your eye protection - high pressure spray plus little interconnected orifices pointing every which direction will give you fine jets coming out of places you would never have thought of...

[Snow]

Finally was able to get around to cleaning the main air jets today, I took out the main jets and pilot jets first. Ken sure wasn't kidding about it spraying everywhere, very glad I wore my glasses.

She *seems* to be running better and looks like she doesn't smoke as much (little anyway) when revving at a stop. The smoke now looks kinda grey instead of black, not sure what that means.

I haven't changed the sparkplugs yet, I may do that this week to see if I need to put a larger main jet in, like 140 (current main size is 137)

She pulls very nicely up to around 6500/7000 and then the power drops a bit, like she is running out of fuel in the fuel/air mixture.

[Geezer]

Mukuni changed the design of the pilot jets somewhere along the line and the new jets in the old carbs run insanely rich.

It's hard to describe the differance but if you have new pilot jets, I'd clean and reinstall the old ones before I went any further.

Geezer

[tony7914]

Originally posted by skids
The emulsion tubes are fairly rugged. I suppose they could wear out, but I don't know how. The jet that feeds them is the pressed-in main air jet in the inlet bell of the carb. Those things could get plugged and cause a rich condition...

Take a peek at the bottom schematic:
http://home.earthlink.net/~sidskids/carbs.gif

It is like the analogy of the hole in the side of the soda straw. Well, the main air jet supplies the air to the emulsion tube. If it is plugged, you get more "soda" and less foam. I am not sure if this makes sense, but it seems to.

hey there!!
any chance you might have a better picture than the one on the link? i can't read the writing very well! thanks in advance!!!

[Snow]

FYI - I've given up on the 78 carbs and went back to fooling with the 80/81 carbs I have that used to work well. I think sometime in the past, someone along the line did some drilling somewhere in these bad boys or something.

I got the 80/81 carbs on, they behaved almost the same as they did before, but not sticking at 4 grand, sticking at 2 grand after I synced em. Well, today I tried a lil experiment and had them idling at 2 grand and resync'ed them at that rpm area, and then lowered the idle to 1 grand. Now she pops right back down to 1 grand after revving and performs very nicely.

It still bugs me that I couldnt get teh 78 carbs to work right, but oh well, I just want a good running bike now.