Need some help

[Radiation]

Hi again. I put a new exhaust system(MAC 4-2) on and noticed a popping on deceleration on the left side out of the pipe. I thought it was an exhaust leak, so I replaced the gaskets on that side. No change. I started messing with my pilots. I noticed that on my #2 carb I can close the pilot all the way off with no difference in idle. If I open it up to much, it starts popping during idle. (too much fuel?) If I close any of the other pilots it almost dies. I took my carbs off and completely disassembled and cleaned and blew out. When I put it back together, it did the exact same thing. I am worried the the popping on deceleration is going to burn my valves. Help me guys, I am missing out on riding weather.

[DiverRay]

I don't think you have ALL of the pilot passages clean. I would also check on the float levels, and the condition of the "O" ring on the needle valve for the float. I don't think the "new" carbs break the pilot needles like the older style did.
A little bit of backfire or popping shouldn't hurt, so you can ride it. I know my bike "burbles" on de-acceleration, but I still get 42 MPG and it runs well.
Just my $0.02

[Radiation]

The o-rings appear to be in good shape. I swapped the needles around with the same outcome. I have my floats set for 25 mm, and they all match. When I cleaned it, I thought I got everything. It was doing it before I pulled them. That was why I pulled them this time. I had carb cleaner spraying out orifices I didn't know I had! I guess I will pull them again this weekend.

[mro]

floats set for 25 mm

80SG float height 23mm, + - .05mm
(from factory manual)


mro

[Radiation]

23mm from where?

When I check my float height, I go from the metal lip where the gasket would normally sit to the flat suface area of the float. Is this right?

[TopCatGr58]

Hey Bill,

Yes, from the flat recessed surface that the gasket sits on to the top/highest point of the float.

Like DiverRay said, the aftermarket pipes do flow a bit better than the oems, and could be leaning it out a little, and with your floats set to high(upside down), it's even leaner. Resetting the floats lower/richer will help, but may not completely eliminate the popping. My 4-1 pops quite a bit during decel when I close the butterflies, and I,too, have new good exhaust header gaskets. I just consider it Godzilla's GROWL!!

[mro]

If whay your saying is that you have the carbs up-side down on the bench, bowls off and are measuring from the float bowl gasket surface (not from the gasket) then yes.......


mro

[mro]

TC speed typer

think I go mow my weeds



mro

[skids]

Re: 23mm from where?

You are no talking about that raised line in the center of the metal gasket surface are you? I measure from either side of that raised line, but not from on top of it.

Originally posted by Radiation
When I check my float height, I go from the metal lip where the gasket would normally sit to the flat suface area of the float. Is this right?

[Radiation]

Thats what I meant. I put the end of the calipers on the inside of the little ridge.

[Lamric]