In Depth
Last month in HOT BIKE we told you the story of how our beat up and neglected '89 FLHS was in need of a complete motor rebuild. After rooting out a few choices, our friends at Harley-Davidson offered to remanufacture our Evolution engine to factory specifications. We sent the motor off to be dismantled and rebuilt by the same folks who built it in the first place.
In this installment, we received the engine back from Harley's Capital Drive plant where the remanufacturing happens. Once the crated engine arrived out west, Kevin and the staff at Harley-Davidson of Anaheim/Fullerton took time out of their busy schedules to put the motor back between the framerails. The engine looks great and it's nice to have major confidence in knowing this Evolution motor was rebuilt correctly by trained professionals with a 12-month warranty.

01. Kevin and Drifty slid the newly remanufactured motor back into our '98 FLHS.

01. Kevin and Drifty slid the newly remanufactured motor back into our '98 FLHS.
With the engine being pretty much brand new, we couldn't just throw the worn parts we had back on it. We needed to update and upgrade a few things. First off, the charging system was shot so we installed a new setup from Spyke. We went with the Spyke system because the Complete Charging Kit ($265) features a forged steel rotor with a thicker spline than stock so it will wear much better. Spyke also uses magnets encapsulated in a protective barrier to resist vibration-related breakage, which can happen to the stock unit over time. To complete the kit, Spyke supplied one of its stators and a made-in-the-USA 12-volt voltage regulator.
The induction system needed some major help as well. We contacted S&S and ordered up one of its tried-and-true Super E Shorty carburetors ($499). With the specially designed Evolution manifold, these carbs are so simple to install and easy to tune that we didn't really want to go with anything else. Once the carb was secured to the engine, we topped it off with a Mooneyes 4-inch backing plate ($18), a K&N 4-inch air cleaner ($39), and Mooneyes Air Cleaner Top ($55) to keep the Super E breathing good and junk free.

02. Both the front and rear motor mounts were installed and tightened down.

02. Both the front and rear motor mounts were installed and tightened down.
We also went with a Compu-Fire selectable advance ignition module ($269). The unit is very user friendly and features two easily adjustable internal rotary knobs; one for advance curves and another for rpm limiter selections. The module also has low-voltage operation with soft start circuitry, so the bike starts easier. Tuning of the Compu-Fire ignition was also made easy due to a built-in LED static timing light. We also used a matching finned aluminum Mooneyes points cover ($45) to dress things up a bit.
Once the stock primary, final drive components, starter, and clutch all checked out to be in reasonably good shape we reinstalled the components and had our motor back in the bike and better than ever.
If you have a tired Evolution or Twin Cam motor and are looking to get it rebuilt, we highly suggest giving Harley a call and going the remanufactured route. As far as the other aftermarket upgrade parts we used, it seems to be a good balance of updated electronics and a well-built, but simple carburetor that made this motor a strong and dependable runner.
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03. A new charging system was needed, so we decided to go with one from Spyke.

03. A new charging system was needed, so we decided to go with one from Spyke.
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04. The Spyke rotor and stator were installed on the crankshaft.
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05. The Spyke voltage regulator was installed in the OE location and plugged into the stator through the engine case.

05. The Spyke voltage regulator was installed in the OE location and plugged into the sta
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06. The stock ignition module was fried, so we went with an adjustable offering from Compu-Fire.

06. The stock ignition module was fried, so we went with an adjustable offering from Comp
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07. The Compu-Fire unit was easily secured in place.
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08. The stock primary, starter, and clutch were reinstalled.
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09. With the drivetrain in line and adjusted correctly, the top motor mount was tightened down.

09. With the drivetrain in line and adjusted correctly, the top motor mount was tightened
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10. A clean motor needs a clean carburetor, so we opted for a new S&S Super E.

10. A clean motor needs a clean carburetor, so we opted for a new S&S Super E.
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11. The S&S carb and Evo-specific manifold bolted into place with nary an issue.

11. The S&S carb and Evo-specific manifold bolted into place with nary an issue.
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12. The Mooneyes universal backing plate and K&N 4-inch air cleaner were bolted to the Super E carb.

12. The Mooneyes universal backing plate and K&N 4-inch air cleaner were bolted to the Su
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13. The air cleaner was topped off with a beautifully cast Mooneyes finned aluminum cover.

13. The air cleaner was topped off with a beautifully cast Mooneyes finned aluminum cover
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14. We also used a cast Mooneyes finned aluminum cover for the cone as well.

14. We also used a cast Mooneyes finned aluminum cover for the cone as well.
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15. All of the oil lines were reinstalled and clamped into place.
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16. With the remanufactured power plant safely back in our bike, this chapter of our project FLHS is now concluded.

16. With the remanufactured power plant safely back in our bike, this chapter of our proj
Sources
Compu-Fire (562) 803-1700 | compufire.com
Harley-Davidson Motor Co. (414) 343-4056 | harley-davidson.com
Harley-Davidson of Anaheim/Fullerton (714) 871-6563 | harleyfullerton.com
K&N Engineering (800) 858-3333 | knfilters.com
Mooneyes (800) 547-5422 | mooneyesusa.com
S&S Cycle 608-627-1497 | sscycle.com
Spyke (562) 803-1700 | spyke1.com