Well, with winter approaching, I am formulating my gameplan for mods and upgrades for my 84 1000cc ironhead. I already know not going to have the cash to bore out or change the size of my jugs. But I want to know what is the best direction to head? I already have pipes and a jetted carb. I plan on upgrading the air cleaner (stock), and mild upgrades on the ignition (bigger wires, better coil). Some what does everyone suggest I do to really make this thing scream? I know parts are tricky to find for these old motors. Seems as if the aftermarket didn't start producing a lot of speed parts until the Evo came along! So whats the best bang for the buck? What route should I take?

 

First note that there is no power to be gained by boring the cylinders. That is used only to refresh worn parts. You can stroke the engine but that requires an enormous pile of $s, and drastically shortens engine life.

There is no way to make an IronHead street bike beat a modern 1200 Sportster.

However, a Mikuni VM38-9 with a Branch backing plate and K&N filter is a nice touch; or a CV carb. A free flowing exhaust like Cycle Shack; the slash cut mufflers have removeable baffles which you can replace with bolt&washer baffles [AKA Lollipops] for a nice LOUD sound; Ultima Electronic ignition.

Check out these ..

V-Twin Thunder [almost impossible to find; may have to pay hundreds]
Carl McClanahan
ISBN 0-933078-12-9

Here ...
http://www.abebooks.com/book-search/isbn/0933078129/

HD Sportster Performance Handbook [chapters 6 and 9]
Buzz Buzzelli
ISBN 0-7603-2353-4

 

If you can find a Screamin' Eagle air cleaner kit for the '86-'87 Evo Sportster, it will bolt right on to your stock Keihin carb. It's a nice setup with an aluminum back plate, internal velocity stack, and K&N filter.

Other than that, I'd spend the money on upgraded suspension and brake components.