Idle on Left Cylinder Only

T

TripleKing

Been Around the Block
We are almost finished with the mechanical portion of our 1970 CB450 project. It runs very well, but will only idle on the left cylinder. I cleaned the idle jet and right carb twice and blew out with air. Air flows through the jet with ease. Air screw and idle screw are adjusted and still nothing. When The throttle is open just a crack, the right cylinder comes to life and runs normally. Putting the choke on also brings the right cylinder to life. I am using Mikuni VM32 carbs with the following jetting:

190 Main
35 Pilot
6DH7 Jet Needle
2.0 Air Jet
159 P-5 Needle Jet

Thx
 
if you screw that idle speed screw in until the cylinder catches is it at a too high idle speed ?
does that cylinder have low compresh?
are the slides in synch,evenly adjusted by cable length ?
 
Slides are synched, compression is 168 psi right, 170 left. I can screw the idle screw darn near all the way in before it catches and then the idle speed really jumps. Funny thing is I had the reverse happen when I first started the bike. Then I had them both working now the right won't fire at idle. Could it be floats?
 
i guess it could maybe be a real low float level
turn the gas off and drain each carb and compare the volume
were the carbs new ? are you sure the pilot jet and passage is clear?
 
They were new when installed two years ago. A shop had it for more than a year trying to figure out an electrical gremlin. They must have tried to start it and let has deteriorate in the carburetors. They were gummed up, hut is soaked them and they are clean and jets are clear. I guess the passages are too as I can get compressed air through. I will check the floats.
 
the one passage that is tricky to verify is the exit passage for the pilot,at the engine side edge of slide area,be sure it is clear
 
I cleaned the idle passage on the engine side of the carbs and set the floats a bit higher (they were a tad bit low) and she idles on both cylinders.
 
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