shovelhead, panhead, or knucklehead?

I say build a Panhead or a pan/shovel.

Knucklehead Frame

a pan will work just fine but if your staying with a 72 frame you might as well stick with a 72 shovelhead.

a belt primary will do away with most of the shovel oil leak problems.

if you want a smooth running engine use the stock 74" flywheels with big bore(3 5/8) jugs. that will make it an 82".

or an 88" with the 1340 cc flywheels & BB jugs is still pretty smooth.

I wouldnt recommend going over 93" (3 5/8x4 1/2) for an every day rider with harley cases because the vibration will cause loose & broken bolts & stock parts like push rod tubes, intake manifolds, oil lines etc. will no longer fit.

with after market cases the skys the limit on size but your going to have to live with the vibration.

ryde on's right, a 93" s&s is your best bet for appearance & reliability.

my current rider is a 96" solid lifter shovel I built up with stock bored out cases 4 or 5 years ago & adjusting the pushrods & drilling & safety wiring bolt heads just aint near as much fun as it used to be. I expect you'll feel the same way about those struts in a few years, dont throw away those shocks. you may need them later on.

'72 rigid frame? 1957 last rigid big twin frame- miss key or a custom frame if 1972. Knucklehead will fit smaller frame than pan or shovelhead- used to have to stretch back at seatpost area of '47 and earlier frames to fit panheads into them. Panhead and shovelhead fit same frames. '72 frame with struts instead of shocks or replaced swingarm with some kind of aftermarket subframe? Clarify please. ** edit: Struts! and probably a inch contour seat instead of big stock sprung seat. get a back twinge just thinking about it. Basic cleaned up shovel be good. A 48 to 52 Pan engine with UL crank would give you a 80 incher - later engine cases had the tapered crank bearings and would need crankpin work- be about as easy to use the S&S crank in a shovelhead. Pans can be built up but Shovels have more parts available. Old knuckleheads should be reseved for the restorers- 61 inch ELs smooth, the FLs had thin cylinder walls and were somtimes known to crack- especially with the UL crank and high compression. have fun. *** Easyriders bike! Fondas was not the best example for street, the other one was practical with front brakes. Springers and spool hubs aren't good for street--but my old chopper is rigid frame with the springer, etc. Can't ride it without attracting police attention as unsafe-- Gold Wing is easier on body and doesn't attract nuisances. Dug out chopper last month from collapsing shed, thinking of tube front with brakes, fender, speedometer and getting some actual mufflers on it instead of gutted shorties.

I recently built a pan which will fit your 72 frame. I put it on a dyno and got 100 honest horsepower. My pan was built using delkron cases with s and s wheels rods wiseco pistons manley valves. andrews gears. s and s oil pump. electronic ignition to. or you could use a s and s shovelhead motor. knucklehead power U.S.A. makes brand new knucklehead motors need a differant frame though.check out Billy lane from choppers inc!!!!

It's up to you, but I've got a soft spot for a knucklehead.

These days a Shovel would be cheaper but I would Build a pan just for looks They will both fit the frame .Ihad a 73 that had a pan engine & open primary looked to good I wish I still had it I have the Shovel in my avatar its personal bike now but I do a lot of road miles and just in case of problems Pan parts can be hard to find in some places

Being your 1st, I'd personally go with the cheapest and simplest. That way with all that could possibly go wrong can be trouble shot with the least losses and frustrations.

Hit your local custom bike shop. The 'mom and pop' places are best because they usually have more time to sit and relive their glory days regarding 1st time malfunctions.

Experience is the best teacher, but you can learn a lot from old schoolers. Good Luck! I'd like to get into the same thing.

S&S makes a shovel replacement( size shape look) with Evo technology and horse power.

That's what I'd use.

V Twin catalog thats where OCC shops, when they want a bike to ride to Ride, They buy a stock Harley, even they wont ride their own bikes.