Cannonball I-Beam Springer Forks

 Certificate

Cannonball I-Beam Springer Forks

Once upon a time when there weren’t any custom parts you could buy from your local shop, the VL fork was a very popular item because it made your Knuckle or Panhead bobber different from the next guy’s scooter. Besides you gained half an inch of length compared to 1936-up Springer forks for improved ground clearance and a more stretched look. Now it’s time to revive those days of the golden 40’s and 50’s with the Cannonball version of H-D’s VL type fork.

Manufactured just like the original, which means I-beams and connecting braces are drop forged on a huge 10 meter forge hammer. This is the only procedure that guarantees these components stand up to the job.

The problems with installing the OEM fork were the large fork stem and the handlebar mounting so the Cannonball fork is modified here. It features a Ø1” fork stem that works with the included centering collar for 1936-up ball bearings. Moreover the stem also features two Ø1” bearing seats for the use of Big Twin tapered roller bearings without any modifications. The leg tops accept the 36-up Springer inline handlebars. This makes installation a snap compared to the original counterpart.

Certificate of stability for 4-speed Big Twins thru 1986. Length is measured from axle center line to seat of lower steering head bearing.

Although these Custom forks are intended for 1936-1957 rigid frame Big Twins they can be mounted with later frames, too, provided you have/install matching frame head bearings. The builder has to consider rake, trail, overall chassis geometry, brake function, etc.

1.) The pivot point of the brake shackle on the backing plate or caliper bracket must not be positioned vertically above or in front of the wheel axle (driving direction). In this case the moving forces in your fork parallelogram will be reversed and the fork will rebound instead of being compressed when you apply the brake. This will generate very high forces to impact on your rigid fork leg with possible damage.

2.) Caliper bracket or drum brake backing plate must float on the wheel axle. If not, the fork will rebound as well when applying the brake. Result: see above.

fits Big Twins
internal thread of neck post: 3/4”-14 UNS
steel
length: 49.5 cm
rake: 0 °
length over/under stock: stock
with material certification
Europe

Internal Threads on the Upper End of the Legs

For custom riser installation the fork legs have M20x1.5 internal threads at the upper end and accept riser adapter studs or plugs which are available separately; an extra added by the manufacturer which saves you a lot of work and axle grease.

Inline vs. Offset

Classic Springer Forks are produced for different frame rakes.

In the beginning, both the main tubes and the steering stem were in the same plane. This is called "inline". The rake is 0°. Of this type were all 45” Springer forks 1936-1957 and all Big Twin forks 1936-1945.
From 1946 onwards the Big Twins had the neck angle increased to 30°. To maintain fork inclination and ground clearance, the steering stem was tilted to the rear by 3°. We call these forks Offset -3°, they were stock on 1946-1948 Big Twins.
When building a bike with ≥+8” extra long forks you don’t want the steering neck so high and inclined that the bike is difficult to steer. Therefore such forks are manufactured with a positive rake, i.e. the steering stem is inclined to the front by 3°. We call these forks Offset +3°.

The sketch shows the placement of the lateral tubes and steering stem seen from the drivers place. Now it is clear, too, why there have to be three different types of top trees or handlebars for Classich Springer forks.

Parkerized Rockers

As a running change the manufacturer currently changes all black powder-coated rockers to a parkerized finish, as it was original back in the days. For a transition period W&W Cycles will have both types in stock, so if this is important for you, please contact our sales staff and let them know your preference.