Upgrading Harley’s 39mm Front End, Pt 4

Even More Forking Around

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Place the oil lock cup onto the end of the damper rod. Make sure it doesn’t fall off or get lost!

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Place the new oil seal over the fork tube, making sure the numbers on the fork seal are facing upward.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Install a new fork damper screw and crush washer; tighten to factory specs.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Using a fork seal installer tool, drive the fork oil seal into place. I chose to use a Jims 39mm fork seal driver (part No. DS-197022).

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Install the fork oil seal snap ring.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Using a small flat-blade screwdriver, verify the snap spring is in its proper place and secure in the groove inside the fork tube.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Place the rubber dust seal over the fork tube and slide it down until it meets the fork lower.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Using the Jims for seal installer tool, tap the dust boot cover onto the fork lower.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Drop the Race Tech springs provided in the gold emulator kit into the fork tube.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Place the spacer washer on the spring and expand the fork tube.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. With the fork tube expanded to its full length, measure the distance from the top of the washer on top of the spring to the top of the fork tube.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. We measured the Speed Merchant preload adjuster and cut preload spacers from the PVC tube provided in the Race Tech emulator kit. Race Tech 45 recommends a 30mm spacer as a good starting point for this year’s Dyna.

Words and Photos: Jeff Leighton

Upgrading Harley’s 39mm Front End

Upgrading Harley’s 39mm Front End, Pt 4

  1. Replace the fork drain screw and crush washer to ensure a proper seal and fork lower that doesn’t leak oil all over!

Words and Photos: Jeff Leighton

Knowing that the stock 39mm fork sets on Harley's Dynas, FXRs, and Sportys need a little aid for maximum performance, we availed ourselves of the glorious bounty the aftermarket created in the front suspension department. Taking advantage of these parts makes all the difference in the ride quality of your Harley-Davidson. We're making a stiffer, better 39mm front end, thanks to Chassis Design Company's trees, Race Tech's Gold Valve emulators and spring set, The Speed Merchant's preload adjusters, Bel-Ray's fork oil, and specialty tools from JIMS USA. If you've been following along in segments one, two, and three, you know this isn't a light undertaking for the novice builder. Here’s our second-to-last segment of the project. Check back with us tomorrow, same Bat-Time, same Bat-Channel, for the final installment of this story.

Sources

Bel-Ray belray.com

Chassis Design Co. chassisdesigncompany.net

JIMS USA jimsusa.com

Race Tech racetech.com

The Speed Merchant thespeedmerchant.net