functionality of the choke

[OSPRNG]

i understand that the choke is supposed to restrict the air flow to make the fuel mixture richer for a cold engine.

does that mean that when the choke is fully engaged, the air intake will not draw any air in?

in my 125SM with the choke fully engaged, i still feel a fair amount of suction if i put my hand against the air intake under the seat.
does that mean the choke is not working right?

[djsbriscoe]

Hi,
I think the choke controls a separate circuit within the carb that provides neat fuel that flows through a drilling in the carb body directly into the intake. When the choke is off the plunger stops the fuel, when its on it allows it.
I don't think it works by directly 'choking' off the air supply. I could be wrong, so if someone knows better please educate me.

David.

[DAVID THOMPSON]

older carbs and older lawn mower carbs restrict the flow of air
newer carbs have a valve that opens and lets in more fuel
the carb on the 125cc bikes is the lets in more fuel type

i have found that if my rt125 sets for 2 months in the winter i have to prime it with fuel in the little
rubber plug on the intake or wrap a piece of plastic around the air filter and crank the bike a bit then take it
off this gets fresh fuel flowing in the carb then it will usually start