Publisher out of print.
Whether you want to improve existing HD factory parts, or install aftermarket components, the Harley Sportster, Buell Engine Hop-Up Guide by Kip Woodring, will quickly become your bible to 883-1200 Harley Sportster and Buell performance.
Fourteen info-packed chapters cover everything, from X-engine history to exhaust, ignition, cams, heads, oil, tranny and clutch.
And this book goes beyond the rest by providing in-depth analysis of topics such as oil and oil friction, design of combustion chambers, camshaft trade-offs, and much more.
Book Excerpt: Harley Sportster, Buell Engine Hop-Up Guide
PISTONS AND CYLINDERS
DISHED, DOMED OR FLAT
It's hard to talk about pistons without talking about their role in determining the compression ratio, or their partner in crime, the cylinder.
This chapter contains discussions of all three, along with a look at Volumetric Efficiency (V.E.), and a separate section on the various ways in which an 883 Sportster can be converted to 1200 or even 1250cc.
Let's start with this much-there are three things that create and affect what we glibly refer to as the combustion chamber. They are the cylinder head, the valves, and the piston.
All of them can be changed or modified to affect how much pressure is available from this chamber. In this case if time is money, pressure is power.
The camshaft variables that affect compression are typically increased duration and/or overlap. More of these mean the chamber isn't closed as long, therefore more of that precious pressure can leak out.
So most of the time, if you add much of these two elements in your hop-up you need to increase what's commonly referred to as nominal compression ratio.
The time honored way to do this has been to take some meat off the gasket surface of the heads or mill them a few thousandths in other words.
Once upon a time, H-Ds employed a built up assembly of separate, individual parts to create what, in lesser machines, would be called a crankshaft. These pieces consisted of connecting rods, big end bearings and cages, left and right flywheels, sprocket shaft, pinion shaft, and various washers and fasteners.
This time-honored arrangement lasted from, oh, about 1909, until 1986, where X engines are concerned. Then things changed. Mostly, the change involved integrating the two shafts (sprocket and pinion) with their respective flywheels.
In short, each half is now one piece. This is a good thing insofar as it makes for a tougher, less flexible flywheel assembly or crankshaft to anyone non-Harley speaking.
Anyway, the real fly in this wheel ointment, is that should you be unfortunate enough to "damage" this assembly-you get to replace the whole thing.
Subject: Transportation: Motorcycles: Performance: 83-1200 Harley Sportster and Buell motors. | ISBN-10: 192913309X | ISBN-13: 9781929133093 | Wolfgang Publications 33093