Carb Air leak

Howdy all, I've got an unusual problem with my rack of carbs. They act like I've got an air leak. When I start the bike, I get a 1050 RPMs on my tach. If I give it any throttle, the bike jumps up to 3500 RPMs and hang there till I shut the bike down then restart. I've done the propane test around all of the usual suspects, boots, hats, ect. I've even switched to flamable brake cleaner to see if that would help. I'm wondering if it's possible that I might have over polished the cylinder where the vacuum piston valve fits? 8O I've blown air through the small top port at the 12:00 position, just above the main air inlet that is on the intake side and, the pistons all seem to be working fine. I've cleaned and re-built the carbs, replacing all rubber parts with new stuff, I've checked & re-checked that all are back together proper. When re-assembling the rack I used a piece of glass to align all of the throats flush. Where else should I be looking? Is there any test to determine if there is too much air getting by the vacuum piston valves?

 

Did you ever figure out where your squeak was coming from? I've kind of narrowed mine down to the manifold side of the carb boots.

Good luck with that hang. I had to replace my gaskets to get rid of mine.

 

Hey Mad, Yeah I found the squeak. I cut new intake manifold gaskets out of that thick blue gasket material and, used permatex high tack to secure them to the manifolds. I coated only the surfaces that would mate between the gasket and the manifold. I used some 220 grit sand paper and a flat piece of glass to clean the manifold surface of any old gasket material and to ensure that they were flat. The gaskets covered what I was calling an O-ring. They seem to work. If I run into any problems in the future I'll be sure to post.