Your idle jets are clogged for #1. I'd put money on it.
What kind of carbs are they? Weber IDF? Sorry if you posted that info, but I am getting dressed for work and don't have time to re-read the entire thread.
Find a good diagram for the type of carbs that you have, and blow out the #1 idle jets with compressed air after giving it a good squirt of carb cleaner. Clean the spark plug. Put everyhting back together and try it again.
If you are making 140# compression, I think you are in really good shape there. If you can borrow a leak tester, it is still a good thing to do.
I still think its easy/cheap stuff. POSITIVE WAVES!
When winter comes, consider pulling and rebuilding the carbs. If you have IDFs it will cost you about $70 (shipping included) for the kits and a few hours of your time.
Fresh rebuild is ~#150 compression. Over 130 is great compression. 130-100 is happy diving compression. 95-100 is start looking for rebuild parts compression. under 95 - pullit and start over time.
Also, you want to have compression in all 4 be ~the same.
AND, compression is just 1 part of the story. You really should do leak down too. You can have good compression, but still have crap leakdown. It sounds weird, but I had 115# compression @45% leak on my #1 cylinder. It lead to a full rebuild, as I discovered my case was collapsing at the cylinders and had to be fixed.
But, really. 140#, I think you are going to be just fine once you get fuel flowing.
Could you take and post a picture of the top end of your engine bay, so we can see your carb set up?
Zach
I had time and I went out and bought a new compression tester and a solid long extension so I could get a good reading on all the cylinders. (The first tester I used was old timey and had a rubber nipple and I believe gave me a false reading of 140ish on #1 and 120 on #3. I couldn't even access #2 and #4 with it.) I warmed the engine up on a 10 minute or so easy drive. I removed all the plugs and opened the throttle while I turned over the engine several times and I checked each cylinder and double checked. I got readings of
give or take one or two on each. Assuming this gauge works right and I hopefully did it right, these readings are not so great. I believe it's time to do the engine shuffle so I can explore the inside of this one.