Bike pops with choke on during cool/cold weather starts

[Spitfire]

The bikes runs well but seems as though the fuel mileage is a bit off at an average of 36 mpg. I've synced the carbs, checked the plugs and exhaust system. It has done it from day one when I purchased it a couple of years ago. The plugs have been removed from the fuel adjustment screws. Guess I'll try to adjust the screws next during the cold weather since I'm only riding on the fair weather days. Other than annoying it doesn't seem to be a problem but I do want to correct it and hopefully improve the mileage. Does this seem like a problem adjusting the fuel mixture screws cure?

[YoDude]

What exhaust do you have? Stock or?
Does the symptom occur on acceleration, deceleration or both?
Poor mileage can very easily be because of low air pressure in the tires, one or both.
Vacuum leaks at the intake manifold(s) will cause this.
Is it one jug that exhibits the symptom or both?

Yo-

[Spitfire]

Acceleration is fine, no stumble or popping, sometimes on letting off of the throttle it will pop. Tires are always checked and adjusted as required before riding. The popping that I'm attempting to eliminate occurs when it is cool enough to require the choke and goes away as soon as the choke is released. I believe the exhaust is not original, they are slash cut style. I think the pop is coming only from on cylinder but not absolutely sure of that. Exhaust seal was leaking at the joint to the muffler but I replaced that right after I got the bike. Don't know about the intake seal but will check them. On a car I could apply a little oil to the gaskets and see if there is any change, any ideas on the best way to accomplish this on my bike? BTW pipes are not discolored, they were a slight yellowish color but I polished that out and it has not returned. Oh, the air filters are good. Thanks for the reply.

The exhaust is the one shown on my avatar picture if that helps.

[YoDude]

In all honesty, I wouldn't worry about the slight amount of popping you're getting while the choke is applied. If you're not getting it after the choke is turned off, then you really don't have any issues that are abnormal. You really shouldn't be riding the bike with the choke on at all. You should let it warm up to the point, you don't need the choke in order to ride it.

In the instance that you're not actually riding the bike with the choke on, it is pretty normal for these bikes to exhibit some popping while they are warming up. Mine does some really weird stuff when it's cold, after that, it's a Lyon!

Yo-

[Spitfire]

Okay, that sounds good. Yeah that is the main problem, sitting in my drive way with the engine popping and so on. Doesn't take it all that long to warm up just annoying while waiting. Generally I don't move it till the choke is off and it idles smoothly. Had it hiccup turning onto the road from my drive once trying to rush it, wasn't pleasant.

[Fred]

The choke is a cold start device and not a choke as in a restrictor of air. The cable splits into two operating both carbs individualy. If one is not working as hard as the other it will be forced to run on a weak mixture and will pop. I would not give it much thought.

[Spitfire]

You know I'm embarrassed to say I never even gave it a thought as to how it "choked" the carbs or the fact that the choke cable split like the throttle cable. Your right, it isn't a big enough problem to waste anytime on for something that only occurs on cold starts for a minute or two. Thanks for the thoughts on it. [emoji106]