I know the choke richens the mixture for starting, however, I'm cleaning my carbs, and I took apart the choke needles on the front of the carbs and sprayed some cleaner in there and it came out by where my diaphrams would be. So my question is, how does that work, does it just restrict the airflow, or is it doing something with fuel somehow to? I ask because I want to clean it out thoroughly since my choke seems to be off, and I also want to know why it dies if you hit the choke when it's warm.

 

The choke on those bikes enriches the mixture. When you move the choke lever you move a plunger back that opens up a port. It is like a mini carb when you open the plunger it pulls fuel from the float bowl & gets air from under the diaghram then the mixture exist through a hole on the engine side of the carb. It dies when you turn the choke on when warm because you are dumping extra fuel into the engine.

 

Couldn't have said it better. That's why it's important not to open the throttle when you're trying to start it with choke and it's cold. These carburetors don't have accellerator pumps like some other types of carbs. If you open the throttle, then you loose the high vacuum that the engine is creating with throttle closed, and it's this high vaccum that allows the extra air/fuel to be drawn through this alternate passage and into the intake manifold.

 

ok, so what are all the parts of it and how would I go about giving each a thorough cleaning to make sure before I button it up? Also, there's carb cleaner in it somewhere I think, will this just dry out if I let it sit for a few weeks, or do I have to get it out?

 

Read through this thread, I think it should clear some things up.

https://cbrforum.com/forum/showthrea...ighlight=choke

 

I would not recommend using a paper clip on any of the jets. They are soft brass & if you are not careful you can make them bigger by scraping & poking them. You will need to get the tool to remove the fuel mixture screw because it is (D) shaped.

 

I didn't use a paper clip. It's the wire from inside a bread twistie-tie. It's 0.0165" in diameter. Much different than a paper clip.

 

So one day IDoDirt was eating some bread and made an astonishing discovery?

 

I just use a tip cleaner kit for gas welding, or something similar they have at the bike shop, that way I have all the sizes I would ever need.