It's like I JUST discovered the choke!

markjs

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Weirdly, for quite some time I had not even been able to get the engine to pop with the choke on. Then when it got colder, it was REALLY hard to start.

So I finally tried the choke and the tickler button again and BOOM, easy start almost on the first try every time. You have to turn the choke off right away to keep it running, but it works now where it would not for the first few months of the engine...
 
Weirdly, for quite some time I had not even been able to get the engine to pop with the choke on. Then when it got colder, it was REALLY hard to start.

So I finally tried the choke and the tickler button again and BOOM, easy start almost on the first try every time. You have to turn the choke off right away to keep it running, but it works now where it would not for the first few months of the engine...
I never need my choke either during hot summer months...lol...Welcome to the club...lol.
 
Weirdly, for quite some time I had not even been able to get the engine to pop with the choke on. Then when it got colder, it was REALLY hard to start.

So I finally tried the choke and the tickler button again and BOOM, easy start almost on the first try every time. You have to turn the choke off right away to keep it running, but it works now where it would not for the first few months of the engine...
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Supposedly if the carb is tuned right it should need the choke in half position until warmed up. A lot of folklore around carburetors.
According to Mikuni a properly tuned carburetor will operate as follows. 50 degrees and below should require full choke to start and may need to fast idle under full choke for up to a minute before being switched to half choke, and half choke will need to remain on for several minutes depending on temp.

50 to 70 degrees the engine should start and run on half choke, but may need full choke briefly to get started and half choke for a minute or 2.

Above 70 degrees no choke should be needed to start, but if the carburetor does not have an accelerator pump to add additional fuel sometimes the choke is still used just to get it to fire off, and then turned off almost immediately.
 
According to Mikuni a properly tuned carburetor will operate as follows. 50 degrees and below should require full choke to start and may need to fast idle under full choke for up to a minute before being switched to half choke, and half choke will need to remain on for several minutes depending on temp.

50 to 70 degrees the engine should start and run on half choke, but may need full choke briefly to get started and half choke for a minute or 2.

Above 70 degrees no choke should be needed to start, but if the carburetor does not have an accelerator pump to add additional fuel sometimes the choke is still used just to get it to fire off, and then turned off almost immediately.
Mine needs full choke to start (40-50f) but won't run on it, or even half choke. As soon as it starts I have to take the choke off completely, or it will die. Seems to run fine without choke, as long as it starts.

I just found it weird how the change was so sudden. I got away with starting it easy at the beginning of the cooler weather, and had a few times tried choke only to get no start at all with it, then when hard starting really set in, all of a sudden the choke worked for me.
 
Mine needs full choke to start (40-50f) but won't run on it, or even half choke. As soon as it starts I have to take the choke off completely, or it will die. Seems to run fine without choke, as long as it starts.

I just found it weird how the change was so sudden. I got away with starting it easy at the beginning of the cooler weather, and had a few times tried choke only to get no start at all with it, then when hard starting really set in, all of a sudden the choke worked for me.
It's the shift in air density. It sounds like you are tuned just a smidge to the rich side, but not overly so. That is how I tend to like my carbs tuned in warm weather. Leans out a bit and makes better power when it gets cold, helps the engine run cooler when hot out.
 
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