Baggy won't idle...

[Lifeislarge]

So I've been working on this bike off and on for a few months now, and finally have it complete after fabricating an air filter cage which turned out to be virtually impossible to find. The bike starts immediately, pulls strong and idles great- if I'm sitting on it. As soon as I get off the bike with the engine running, it dies. I can only surmise that the seat seals the airbox and as soon as I get off the bike, it gets too much air. The carbs are immaculate and set up according to the manual. I'm at my wits end and looking for the fix that I know I'm missing...

[DAVID THOMPSON]

how about the sidestand switch
when you get off the bike the weight shifts on the side stand and turns it off

i am still scratching my head about the way the sidestand switch works in the scheme of things

so if you have a center stand try it and see what happens
or just unmount and hold it up and see if it dies
and are you idling it too slow
speed up the idle a bit

these are very short stroke motors and do not like a putt putt idle speed

old time singles were long stroke and could be idled down to almost stall speed
old bmw bikes before 1969 would run real slow but they did not oil well
and many a good bike lost its crank bearings in short order
my r50s was bought in a basket because the past owner liked to idle it at almost stall speeds

[Lifeislarge]

No it has nothing to do with the side stand switch. Idle with me seated on the bike, in neutral, is probably somewhere in the neighborhood of 1200 RPM. Whey they decided a tach on these bikes was unnecessary is beyond me. Either way, it's strong and not in the least bit lumpy. It has to be something to do with the mixture and the airbox/seat combo. Tomorrow I'm going to put a lid on it in different positions to find the sweet spot.

[breakwellmz]

Seat on or off on mine makes no difference to idle speed.

I wonder if there is some bad electrical connection being affected by your weight on the seat?