The B.D.A.C.

When I bought my 1980 FXWG, I was told that there was a 96" S&S kit in the motor. It's leaked from the time I got it from the rear base gasket and wept from other areas, but about a week ago it started POURING from the front rocker box, so I knew it was time to put her up for winter and start the total bike tear down since I'm changing most of it.

Today, I was starting to take everything apart and while I was in there I pulled the timing plug to read the numbers on the flywheels. S&S flywheels have a code etched into them that allows you to read the date, what model it's made for, as well as the stroke and diameter. The 96" S&S kit comes with 4 5/8" stroke flywheels and 3 5/8" bore pistons. The code for a 1980 model with 4 5/8" flywheels is XXXXX-6SE, but mine read XXXXX-3SE, so using the instructions on the S&S website, I decoded it to be a 4 3/4" set of flywheels. So since the jugs are S&S and the motor is in a 1980 model, it leads to believe that I was not mislead about the bore of 3 5/8" since there would've been no reason to replace the jugs for the stock 3 1/2" bore. That being said, this motor comes out to 98"...a nice suprise considering when you're wrong on this kind of thing, it goes the other way. That combined with the likelihood of a 9.78:1 CR according to S&S, then I'm not surprised this thing is not the easiest to kick.

Here is the site for the flywheel decoder:
BOOM