Harley Davidson 96 Inch Evo Engine Rebuild

Those of you who are regular readers of HOT BIKE magazine have no doubt been following our 96-inch Evo build. For those of you not familiar with the project, here's a quick synopsis: Our goal was to build a strong and reliable, streetable motor without the restraints of using components packaged as a kit. Rather, we wanted to pick and choose parts we felt would work well together once combined to help us reach our goal.

To this point we have a complete bottom end consisting of Harley cases, a JIMS stroker flywheel, a TP Smart Pump (oil pump), a Dave Mackie DM 595 cam, and an S&S reed valve-style breather.

As we planned, we toyed with the idea of using a set of aftermarket cases. After weighing the ups and downs, we decided to stay with the stock Harley cases in order to keep the serial numbers consistent between the engine and the bike. This could prove to be a big plus when dealing with Johnny Law, or for whenever we decide to sell the bike.

This month, Bob and Eric Bennett of Bennett's Performance in Signal Hill, CA, will be fitting the JE pistons into a set of Axtell cylinders, then topping them off with a pair of STD heads. The cylinders we chose are a set of Axtell cast-iron pieces (part No. 200-028; MSRP: $915 per pair). We decided to go with cast iron versus aluminum because the cast-iron pieces are extremely stable, and will remain straight and true for many years to come. Axtell manufactures the cylinders utilizing a one-piece cast-iron design, unlike an aluminum cylinder, which has a cast-iron sleeve fitted to it during the manufacturing process.

We will be attaching a pair of flat-top JE Pistons (part No. 161947, included with the Axtell cylinder kit) to the JIMS connecting rods. Based on our calculations and the dimensions of our components, the engine will have a compression ratio of 10.6:1. This should allow us to run the bike on premium pump gas without any problems. The final components we will be installing this month will be a pair of STD Stage IV cast-finished heads (part No. 1990; MSRP: $1,678). Features of the heads include STD's bathtub-design 1.650-inch exhaust, 1.940-inch Kibble White Black Diamond valves, and Crane premium valvesprings. The highly efficient, ported and polished heads are designed to flow 320 cfm at 28 inches of water (different manufacturers rate these figures differently, so for comparison purposes make sure you are talking apples to apples when looking at different heads).

Bob began by bolting up a set of torque plates to the Axtell cylinders. He then used a bore gauge to accurately measure the cylinder bore; it measured 3.625 inches at the top, middle, and bottom.
Bob began by bolting up a set of torque plates to the Axtell cylinders. He then used a bor
Axtell included a set of JE pistons and gaskets with the cylinders. The pistons came complete with wrist pins, locks, and a full set of rings. Once unpacked, they were measured with a micrometer. They came in at .0035-inch smaller than the bore in the cylinder, exactly what we were looking for.
Axtell included a set of JE pistons and gaskets with the cylinders. The pistons came compl
Before proceeding further, Eric placed a Cometic base gasket over the cylinder studs prior to checking the rear cylinder for clearance. There was a bit of interference at the bottom of the cylinder and fin and the lifter block. The affected areas were marked with White Out.
Before proceeding further, Eric placed a Cometic base gasket over the cylinder studs prior

With the cylinder on the bench, a little attention from a die grinder was all that was needed to allow the cylinder to fit squarely on the case. Just a touch of black paint, and the cylinder looked like new.
With the cylinder on the bench, a little attention from a die grinder was all that was nee
Eric used a set of KASTAR cylinder hold-down nuts to secure the iron cylinder in place. This allowed him to measure the deck height (dimension from the top of the cylinder to the top of the piston at TDC). He did this with a straightedge and a feeler gauge. The measurement came out to .015 inch; we were looking for .005. We got there by swapping out the .020-inch base gasket for a .010-inch base gasket- simple as that.
Eric used a set of KASTAR cylinder hold-down nuts to secure the iron cylinder in place. Th
Bob then used a feeler gauge to check for proper ring end gap. He likes to have .0045 inch per inch of bore for an iron cylinder. Based on a 3.625-inch bore, we were looking for just over .016 inch of gap for the rings. They measured .018 inch, which should be just fine.
Bob then used a feeler gauge to check for proper ring end gap. He likes to have .0045 inch