Honda CX 500 Forum banner

Apparent but mysterious choke malfunction

413 Views 13 Replies 8 Participants Last post by  Mason
Wondering if anyone has run into this. Difficulty with cold start which seems due to the choke not choking properly.
It seems to choke about as it should with it pulled halfway you get the rpms you would expect but then when you pull full choke the rpms drop way down
When the engine is warm then when you pull the choke full it goes up to 3000rpm
But with a cold running engine and full choke it almost dies, I push the choke in halfway and then it will run at 2000rpm to get it warmed up, once warm she idles perfect and runs just fine
Not sure what's going on? I did take the carbs off and checked to see if the 馃 was totally closing at full choke and yes it is....Thoughts?
1 - 14 of 14 Posts
First experience with a manual choke.

The full choke position is making the mixture too rich for the bike to run. Ie, not enough air with too much fuel. Warmer temperatures require less choke.

I don't believe anything is wrong with the choke.
  • Like
Reactions: 3
The choke plates are spring loaded so that they can open slightly dependent on the air flow. If you have the carbs out and you press on the choke plate it should partially open easily. If not there may be a problem with the mechanism.
First experience with a manual choke.

The full choke position is making the mixture too rich for the bike to run. Ie, not enough air with too much fuel. Warmer temperatures require less choke.

I don't believe anything is wrong with the choke.
Wow nice try
Newt may be right but if you have the carbs out to look at other things it wouldn't hurt to check the fast idle adjustment (the FSM describes this better than I can).

Also, have you balanced the carbs yet? Misadjusted carbs can do funny things....
  • Like
Reactions: 2
Sounds exactly like my cx500's choke has been for the past 30 years :)
  • Like
Reactions: 1
Wow nice try
What don鈥檛 you believe? My choke operates about the same you describe yours as being. I find it to be perfectly normal. Pull choke out fully and start engine. As soon as it starts push choke in until it runs smoothly. Usually within 30 seconds or so the motor will start reving higher so I push the choke in a little farther until the motor runs a slightly high idle. By the time all my gear is on it is ready for the choke to be opened all the way and ready to ride.
  • Like
Reactions: 3
That's good yours operates that way sounds like what it's supposed to do
That's not what I'm experiencing with mine, if it was I would not be asking for advice
Maybe read the initial post again and see what you think, better to ask questions than assume
Maybe I'm not describing the symptoms well enough
Maybe I'm not describing the symptoms well enough
When you do a cold start do you use full choke or part choke? How long after start up before you adjust the choke? Full choke is just for starting the engine then it should be adjusted based on how the engine is running.
  • Like
Reactions: 1
So yeah I'm fully versed on how to operate a choke on one of these so we can rule that out:) I know what rich or lean means etc...
Let me start from the top If the bike is cold in the morning usually I would pull the choke all the way out and it should basically start right up however it putters tries to fire then I push the choke in half way and then it starts altho reluctantly and I'll have to fiddle with it pushing and pulling the choke till one spot seems to be the right spot at which point it will run as it should and I can let it warm up
Maybe there is a fuel delivery issue related to the vacuum pet cock?
I thought maybe the cable was catching somewhere but have not located that
Or maybe it's one of the springs mentioned earlier, I'm not sure what that is tho
Have you tried a cold start without the choke? The Grub doesn't want any choke until late November. It stalls if the choke is applied.
Wow nice try
Sure....anytime. I'll hesitate in the future. :cautious:
Maybe I'm not describing the symptoms well enough
No, you didn't
1 - 14 of 14 Posts
Top