My 750 chopper had always ran fat on cylinders 1 and 2 and almost to the point of lean on 3 and 4 since the day I brought it home. It still ran finally decent until I started to put some miles on it doing the last few warm days of fall here in downtown Virginia. It finally got to the point where it fouled the plug on #2 and I came in sounding like miss firing machine gun. I had received an extra set of carbs with the bike that the rack, tops, and bowls had been chromed. Knowing I would be probably experimenting with jet sizes and after researching some posted set ups here for pods and straight Mac 4 into 4's, I ordered carb kits and an assortment of main jets. Figuring I could save some time by switching the racks back forth with different jet sizes to find that sweet spot I planned on rebuilding both sets. I tore down the extra chrome set first and found although they had not been mounted on a bike for quite awhile, they were clean, and in pretty decent shape. The chrome was showing its age in several spots but they cleaned up nicely and they had the following set up installed:
135 mains
40 slow jet
needle clip in the bottom slot
mixture screw 1 1/2 turns out
(I summarized someone must have been running a bike that needed a s&*^tpot of fuel.)
Next I pulled the set that were mounted on the bike. After tear down I wondered how the bike had ran at all. They were dirty with a lot of rust on internal slide shaft mounting brackets. There were jetted with the following set up:
110 mains
40 slow jet
needle clip in the second from the top slot
mixture screw 1 1/4 turns out
If I am not mistaken, that was pretty close to the recommended stock setup.
With the dirty set still on the bench, I set the chrome rack up as follows:
125 mains
40 slow
needle clip in the center notch
mixture screws 1 1/4 out
I also bench synced the set as close as I could and having the patience of a "Tit Mouse" I went ahead and stuck them on the bike. From the first start up, the bike ran like a different machine, no hesitation with very little decel popping, and best performance ever. I pulled plugs 1 and 4 after a short run and perfect color. The only adjustment made was to the idle, but in fairness I still need to put in some additional miles to see if any further dial in is needed. I also really like the little extra bling the chrome gives. I am still going to rebuild the set that came off the bike and may be picking up another project 750 in the morning that has been sitting for years, so they will see use. I just wanted to post this experience to let others know what worked for me, and sometimes you just have a good lucky day. For further reference my bike runs electronic ignition and has had an 836 kit installed....
