Jackpiner Starting

[Gary Brinton]

Hi:
I just replaced the Mikuni on my '72 with a Bing 84.  I can jumpstart the bike and it will run for about 30 seconds and then start to cut out.  If I pull in the clutch, it will then start to run again then cut out again.  Eventually, it will stop running.  Then if I start kickstarting the bike, it will run for about 3 seconds then quit.  I've fiddled with the float height and played with the petcocks to no avail.  Any thoughts on my problem?

 

[john durrill]

Gary ,
 what type of choke circut does the Mod. 84 use?
 what do you have for a pilot jet and  what drill do you use to start it?
John

 

[Gary Brinton]

John:
The choke is a slide assembly that goes up and down with in the piston assembly.  To start I set the choke slightly on, tickle the carb until it is overflowing and then kick.  However, since this problem has started I have to bump start the bike.
Thanks,
Gary

 

[Paul Danik]

Did the bike start and run normal with the Mikuni ?  The reason that I ask is that I have had several times when a machine had to be bump started because the moto-plat was to weak to produce a healthy spark at low RPM?  I cleaned and cleaned the carb only to find that the problem was the juice maker!!!
Paul

 

[Dave Withrow]

Hi Gary,
    Does the motor sound like the carb is loading up?  I have a '77 400 MC with the handlebar mounted choke control.  Sometimes the choke lever would vibrate around to the "choke" position.  I finally just switched carbs.  Just a thought.

 

[Gary Brinton]

Paul:
Occasionnally, I would have a problem starting the bike with the Mikuni.  I'm going to put it back on today and see what happens.  I was also thinking the motoplat might be the problem.  Although usually the problems like this are carb related.
Thanks,
Gary

 

[Doug Wilford]

Check the atomizer, if it was put in backwards the bike will attempt to run, but fall on its face dead.   The atomizer is the brass piece that sticks up in the bottom of the venturi, the half round goes towards the air box, and square it off side to side.