Better Braking on a Budget | Fork Tech

49mm Dyna dual disc upgrade

We have a 2011 Harley-Davidson Dyna Street Bob and wanted to give it better braking performance up front, but we didn’t want to spend thousands on this project and break the bank while doing so.

We already had a set of calipers, a newly powdercoated 13-spoke mag, and some brake rotors that were all “take off” parts from a few other project bikes of the past, so we had most of the needed parts just sitting in a box on our shelves.

Using this mismatched componentry we knew it was going to take a bit of planning, measuring, and some basic machining skills to get our pile of parts to work together in unison. Nothing too complicated really needed to be done to make these parts work besides finding the right set of fork lowers. After figuring out what was available with 49mm dual-disc from the factory, we used a set of H-D dual disk lower sliders (part #45500273) from the Harley-Davidson Parts & Accessories catalog that are used on 2014–2016 Dyna Lowrider models. From there we were able to construct a dual-disc setup on the cheap using nothing but new and used OEM Harley-Davidson parts. Here’s how we did it.

49mm Dyna dual disc upgrade

Here is the Blackout Lower Slider Kit from H-D’s Parts & Accessories catalog. It comes complete with all sorts of goodies needed to make this conversion happen.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Our buddy Jim at IMZZ Elite was kind enough to lend us a hand in this conversion. He started by draining the fork oil and removing the old for lowers.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Jim then inspects the forks for any wear or worn out parts. Then he installs the new fork dust caps and seals onto for tubes.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Anytime you are rebuilding the front end do yourself a favor and always use brand-new OEM seals and bushings from Harley-Davidson.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Jim then installed the H-D fork seals into the fork sliders with a 49mm seal driver.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Once the seals were installed correctly Jim carefully inserted the C-clip into the fork lower.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

The lower sliders were attached to the fork tubes via Allen bolts and torqued to factory specifications.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

The H-D dust caps were affixed to the lower sliders with a series of chrome set screws.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Up top, the fork caps were removed to gain access to the hydraulic system of the front end.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

A predetermined amount of Bel-Ray 10-weight fork oil was measured. The amount and viscosity of oil can vary by what internals are in the front end and the rider’s weight and style of riding.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

The fork oil was then carefully added into the top of each of the fork legs.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

The older 13-spoke mag wheel had to be internally machined and larger bearings had to be installed for it to work with the larger axle of the 49mm forks.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

As you can see the 13-spoke mag wheel is narrower than the stock 49mm wheel used on the newer Dynas so there are some spacing issues that need to be rectified.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Once the wheel was deemed to be perfectly centered in the forks Jim measured the gaps and machined the proper spacers.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Spacers for the H-D calipers to properly fit on the brake rotors also had to be made.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

When upgrading to a dual-disc setup over a single disc, a different bore brake master cylinder has to be used to push the proper amount of fluid equally to the two brake calipers. We found this one off of a totaled bagger for cheap.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Up top the good-looking black H-D covers included in the kit were installed.

Words and Photos: Jeff Leighton

49mm Dyna dual disc upgrade

Once the brakes were bled and the bike had a few brake-in test miles on it, we were very happy with the outcome of our budget brake upgrade. The bike has much more braking ability, and that’s a real good thing when you need it.

Words and Photos: Jeff Leighton