Vacuum Leak #1 carb

[Sharkey]

I have a vacuum leak on the top of the #1 carb somewhere. I get a miss and popping. It will smooth out when I spray a little carb cleaner toward the top of the carb.
Any ideas? Do the diaphrams that pull the needle out of the main jet go bad? I need to rig up a way to run the bike with the fuel tank off for a better look.
The boot to the intake is tight, and I have a new vitron O-ring in allready.

[fudgie]

There is a real short line up in the carbs, maybe the back of them. Its like 2" long. Someone years ago had a problem and it was them lines. It may have been chip, I cant remember. Looks up, under, and to the back of the carbs. Let us know how it turns out.

[Patrick]

There is a short hose to the air valve and its probably about time for them to start deteriorating.. I think a friend had this problem a number of years ago..

[shortleg]

  Try to take top of carb off and take
a look at the diapham.
  Also where around the carb are you spaying?
          Shortleg[Dave]

[Sharkey]

I took off the cover for the choke cables, and found there was a loose screw on the bottom of the diphram cover. I love a easy fix.

Fudgie I see the short piece of vacuum line you are talking about. I might replace those next time I have the tank off. Is there a better line than just the rubber hose you get at the autoparts store. A silicone or something?

[fordmano]

For those little 2+" long rubber hoses if they are the one on the side of each carb they are for the Air Cut Valves.

Talk to Rich from Redeye those come in his O-ring kits and you can probably swap those little hoses without pulling the CARBS out but if you end up pulling the carb rack might be time to change all the rubber parts in the CARBS anyway.

OH by the way, glad you found the problem and it was an easy fix this time.