[AgentX]

Anyone here know how to op-check the choke (enrichener) on a Mikuni TM32?  With it engaged, when I blow through the tube that sits in the bowl, it exits the proper outlet in the venturi.  So that's good.  But should it be totally closed off when I blow through it with the enrichener disengaged? I can hear it exiting somewhere but can't pinpoint.

[A bad enrichener would certainly explain my sudden super-high idle speed followed by dying off...!]

[ace.cafe]

I wouldn't worry about it. It's probably coming out from the feed in the fuel bowl when you blow in it. I have never heard of a bad enrichener.

Much more likely to be an air leak at the head/manifold joint, or a hole or leak in the rubber radiator hose between the carb and manifold.

[AgentX]

Much more likely to be an air leak at the head/manifold joint, or a hole or leak in the rubber radiator hose between the carb and manifold.

My first thoughts were just that, but I can't find any such thing.

I've confirmed/checked/reset fuel supply, timing, mixture, disconnected my switchgear and gauges (installed new tach, wanted to make sure it wasn't messing with anything).  Valves were perfect when the bike was dead-cold before I started for the first time.  Obviously gave the carb a good going-through.  Tried an alternate spark plug, no change.

Yesterday, I did adjust the timing a hair, but I rode it afterward and had no difficulties.  When doing so, a points plate screw finally gave up...it had been hovering on stripped since I got it.  So I drilled and tapped using a Hitchcock kit that I had sitting around against the case.  Was careful, used grease in the bit, and cleaned up afterward.  I had to file the plastic Boyer plate a little to accommodate the larger screw shank.  But it's sitting fine.  And I rechecked, found no shavings or anything inside.

Am resetting the timing once again, and will try a third spark plug and see if that helps any.

Sigh.

[Tarnand]

Bullets are too often unpredictable.  I realize that my question may sound somewhat odd but let me ask you what is your spark plug gap?
Believe it or not but I had similar experience and the problem went away after I readjusted the gap to factory recommended 0.5mm.

[AgentX]

Turns out my decomp valve, the stem of which I'd had to straighten, is bad again.  Chamber wasn't sealing.