Hi All
I recently got some Mikuni VM 28 Carbs on the bay and found that the Choke valves have springs so when you release the choke lever they spring closed and the lever moves to run...
Q - Are all the VM 28s like this ? as my original ones didn't have the springs which may explain the really slow throttle response back to 1100 rpm.
Any thoughts Welcome
Ta
Ian
Hi
Yes spring pushes choke valve down to seal the enrichment circuit using the rubber top.
If this doesn't seal you will have too rich a mixture causing the motor to run sluggish.
To add to what has already been said, all Mikuni "chokes" use a spring to push the plunger back closed. That applies to OEM carbs, VM series, TM, TMX and so on. The spring is a common part.
BTW, are they actually genuine Mikuni carbs and are they actually 28mm in the bore (not the slide which should be around 30mm)?
