NEW! DISC BRAKE KIT for 74 Spring fork

While there were few good disc brake kits for springers available both in Japan and overseas, thanks to the extraordinary passion of our company and our partner developers, we have finally created a pretty good brake kit!

Until now, converting a stock Type 74 springer fork to a disc brake was a time-consuming process.

When installing disc brakes using the existing brake rod tabs, the springs move in the opposite direction.

We won't go into too much detail here, but this occurs when the direction of the force exerted when braking to stop the rotor's rotation acts on the fork springs without changing direction.

On a typical motorcycle, whether it's a telescopic fork or a springer fork, when you apply the front brake,

① The load shifts forward. This shift in the center of gravity increases the load on the front tire and decreases the load on the rear tire.

② The increased load on the front tire, along with the front suspension's sagging effect (spring reaction), increases the tire's contact area.

This is why the front brake is generally more effective than the rear brake.

(You probably learned this in driving school.)

Now, imagine this on a wet road.

If the springer fork is in the reverse position (lifting up when braking),

it's easy to imagine that the front tire receives less weight, reducing the tire's contact patch.

Simply put, it's quite dangerous.

So, installing a regular disc brake requires:

"Cutting off the existing tabs,"

"Repositioning the tabs,"

"Welding the tabs,"

"Repainting the forks,"

As experienced repair technicians know, it's a time-consuming process.

This disc brake kit is designed to be completely bolt-on.

We developed it with a thorough understanding of the disc rotor diameter, torque rod position, wheel type, and ease of maintenance from a mechanic's perspective.

We decided to use Brembo calipers for the caliper body after considering future repair part availability, product precision, and compatibility with commercially available master cylinders.

Since the springer fork structure itself is a fork design from over 70 years ago, we decided that excessive braking force from disc brakes would be dangerous to the fork's strength.

As shown in the photo, we repeatedly tested disc rotors of various sizes, thicknesses, and materials,
deliberately achieving a design that is neither too effective nor too ineffective.

Of course, no welding is required to move the tabs.
Everything except the master cylinder is included in the kit.

The wheels were designed for double-flange wheels for excavators from 1972 to 1984, which are the easiest to obtain, both used and new.
This kit has been confirmed to fit wheels from 16 inches to 21 inches.

Before adopting the double-flange wheels for excavators, we also prototyped Evo aluminum hubs.

This hub had several variations in offset depending on the year of manufacture, which often resulted in individual differences in tire centerlines. This resulted in its inconvenient use and led to its rejection.

Next, we tested it with a Star Hub Timken bearing-equipped wheel.

This one also lacked torsional strength due to the thin axle shaft, and was rejected due to its price and the limited availability of new and used springs.

Compatible springers include:

Genuine NEO Factory Type 74 springer forks, W&W Genuine Type 74 springer forks, European (Samuel) Genuine Type 74 springer forks, and V-Twin Genuine Type 74 springer forks.

Other genuine drum brake 74 springer forks may also be compatible as long as the springers are manufactured to the same dimensions as the original.