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Back In The Day

45" Flathead Engine

The engine was completely rebuilt... with some new features:

	High-Compression Aluminum heads
	.030 oversized JCC pistons
	Machined relief in heads for taller pistons
	Machined oversized valves
	Higher grind cam gears (WLDR)
	Fairbanks Morse Magneto from a 1968 Sportster
	34mm VM34 Mikuni carburetor
	Drag pipes
	12 Volt Generator - Chrome
	New oil pumps
	Chrome push rod covers

New rods. All new bearings: crank, cams, push rods. Rebuilt oil feed and scavenger pumps. New breather valve and idler gears. New flutter valve and oil pressure switch. New inlet pipe, manifold nuts, compression bushings, head bolts, cylinder bolts.

Cylinders and Heads

The cylinders were in good shape. We welded a little chip in one of the exhaust ports where the header connects and touched up with a little high temperature paint. We used pistons that clear the top of the cylinder by .033" to flush all the exhaust gas out of the cylinder. To do so, we also had to machine the heads to provide a .035 relief so the piston wouldn't hit anything bad...
	We topped off the cylinders with a copper gasket. This gives us a comfortable margin of between the top of the piston and the bottom of the head and should produce a good "squish" factor within the combustion chamber to get the bad old air scurring out of the cylinder.

Drag Pipes

Well, the drag pipes were a good idea... we thought they would look good and be less in the way. Well that was wrong. The front pipe fit ok, but the rear was in the way of everything. We bent pounded and cut about 1 1/2" out of the pipe to clear everything... of course we had to run the shift linkage behind the transmission because things just got a little too cluttered where it wanted to go. We put a couple of inserts into the ends of the pipes and hope that will suffice for mufflers.

While the front pipe didn't need cutting, we did weld a tab on it so we could hook the spring for the magneto on it. This served two purposes; (1) To help hold the pipe in and (2) provide a straight shot for the magneto spring.

Magneto

Rather than the stock coil and distributor, we decided to use a magneto from a 1968 Sportster. The pre-72 magnetos fit the 45 case without any modification. I'd heard bad things able a small spark when kick starting, so we added an external, high-capacity Blue-Streak condenser for that little extra spark! Fires on the first kick or so.

We used an Accel battery eliminator and rectifier so we can run lights without needing the battery. An Accel solid-state voltage regular mounted under the solo seat keeps the electricity pumping at the right levels.

Gas/Oil Tank and Capacity

Gas and oil tank were original... from something anyway. They were cleaned and sealed and have no leaks. We kept the leaking engine case just to make sure it wasn't too different than the old days! Oil tank holds about 3 quarts. A little dip stick inside the cap of the oil tank tells us when it's time to recharge. The owner's manual says, above 32F use 50w. After checking around a bit, I was told to use a "racing" type oil so I'm running VR1 50 (or 20w-50). AutoZone, O'Riley's, and Advanced Auto all carry it.

Carburetor & Fuel Lines

We definitely didn't want to use the old Linkart carb, so we went with a new 34mm VM34 Mikuni carburetor. It was connected to the gas tank with a 5/16" hose and clear fuel filter to make sure we weren't putting a lot of left over junk in the engine. We also swapped out the old "Instant Reserve" for a regular petcock with a reserve switch. Much, much simpler to use that the original reserve mechanism. Reserve switch forward and normal on in the rear.

But... Does It Run?

We had no idea what to expect. There has been so many modifications to the engine, carb, ignition, cams that we didn't know if it was going to run or blow up in our face. We hadn't been able to start it because we didn't have the motor pulley fabricated and no way to turn it over. When we finally got the pulley done, we couldn't wait to see if it would make a noise. We put the pulley on, filled it with oil, added a little gas, and kicked it over. We didn't have to wait long.

Hell Yes!!

As soon as we got fuel in the bowl, it fired and ran perfectly... it didn't even pop... just ran. June 17, 2005, it has been a long time coming. Kade and I just stood there looking at each other with big dumb smiles on our faces.

We were afraid we didn't get the nut tight enough on the motor pulley and Kade said, Shut it off!. I just switched the key to off and the motor stopped. Amazing! We checked the nut and kicked it again. Started on the first kick. Throttle response was great... sounded great... we just looked at each other in shock. Switched the lights on... they worked. Just too much to take in. Ok, well we don't have the chain on or the shift linkage together so we couldn't go anywhere but it sure gave us an incentive to finish this up. Kade left a little while ago to machine the motor pulley down a bit, put a fence on it, and pick up some last minute hardware.