Harley Engines: Overview of Upcoming Series

As a new riding season is getting started, we will be rolling out a new series of blogs focusing on Harley Engines. In the upcoming weeks, we’ll provide you with a focused series describing personal experiences with the soul of these iron horses.

Panhead EngineSome of the things we’ll dive into are what makes these engines so iconic—there is certain feeling you get when you ignite a motor you’ve stripped down, be it from a dead-in-the-water wasted afternoon, or a complete overhaul to turn a once stock engine into a fire breathing beast.

We will be covering all the motors from 1936 to present and encourage you to send us your suggestions on what you want to know about.

Along with stories from builds gone right and wrong, we will be going over the trends we’ve seen from an insider’s view, from the early stroked out Sportsters to the Twin Cam gear drive camshaft upgrade. We are going to cover DISPLACEMENT: “there is no replacement for displacement.” We are going to cover bling: can you remember the first time you saw diamond cuts on engine fins? All of this and more.

First things first, a timeline of Harley engines:

Sportster EngineToday’s factory Twin Cam 103 cu. in. did not get plucked from thin air—it grew out of need. Go ahead, I know half of you are saying to yourself, “a need for speed.” There was a decree from the Motor Company to its engineers in the mid ‘90s to develop a new motor. One that did not go against 60 years of tradition and expectation.

We’ll start from the beginning with the EL Knuckle Head, roll on into the Pan Head, farther down the line move onto the Shovelhead, and into what had already been an evolutionary process of a single camshaft, the iconic 45 degree engine, the Evolution Engine.

Ahh, the Evolution Engine. The motor that saw H-D step out from the shadows of the AMF conglomerate—its 16-year run that made the world a better place. A motor that barely marked its spot in the garage with tighter tolerances, the base for incredible displacement increases, all the way through the 124” S&S or 140” Ultima.

Twin Cam EngineAnd now, 15 years have come and gone since the Twin Cam took the reins. That one-camshaft-too-many motor is starting to see real displacement increase: enter the S&S 143” Twin Cam, but more on that in a later post.

This is just the spark that gets us started. Our journey down this road will be winding. As with the best rides, there is a general destination, but getting there is what the story is really about. Our destination is to cover what makes us riders work those long hours, sweat over what some think of as mere metal.

For a more detailed timeline, check out this historic timeline of engines from 1911-2012.

I reach out to you fellow engine enthusiasts: What motor gets you down the road? What crank turns your dial?

Stay tuned for our next installment where we will dive into the Twin Cam engine. We will cover the standard specifications, you know, the things that you hear rattled off: “that cam has .510” lift,” “these cylinders have a 3.927” bore” and things of that nature. We will cover some of the similarities and differences between the multiple Twin Cam versions.

Until next time, let’s see how many miles we can get closer to that next oil change in this 50-degree, Midwest weather.

By | 2015-04-14T16:16:50+00:00 March 19th, 2015|Categories: How-To Articles|3 Comments

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3 Comments

  1. Mike Kersting July 14, 2015 at 1:17 am

    I’m a 1st time HD owner, recently purchased a 07 Electra Glide standard, as much as I am loving my new ride I also want to make sure I keep up on all maintenance. I will definitely be following this series.

  2. Nomad Nomlaki April 24, 2015 at 7:52 am

    I currently own a 2007 FXDB had SE 103 kit put in before picking it up. Added Thunder header with Thunder Max self tune. About ready for rebuild @ 65,000 whereas I scorched a rear cylinder in Street Vibes being trapped in traffic. When I took bike home rear brake caliper would stick and turn rotor blue. HD dealer said I was riding too aggressively? Eh? I never went over 50 mph for first 600 miles to break in. Had couple other annoying things HD dealer said was normal? However I replaced bad stuff myself and cured problems. After warranty was up HD dealer said he would fix things I already did myself? Yeah-Right! One thing that maybe J&P might have article on is the inherent bad end Crank shaft bearings that cause Cam chain tensioners to wear and why Harley just relaxed their forever end play tolerances on Crank play. Instead of fixing the bad cam chain adjuster they offer SE cam chain set with that $70 minute tube of special fastener glue. I made appointment to get right turn signal button replaced.
    The mechanic at dealer wanted to put bike on their analyzer machine before he could fix bad switch. WT? Obviously the switch was bad. The dealer charges $85 to hook up machine and 1/4 hrs. labor for tech to use it. BS. I bought new switch from Drag specialties and fixed it myself. Stealership wanted over $300 to change turn signal switch. I did it in 20 minutes.

  3. Bob Colapietro March 19, 2015 at 4:28 pm

    Looking forward to this series!

    Big panhead fan… :+)

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