Part I – Building A Custom Bobber

It Starts With A Frame

You can WIN this Brass Balls Bobbers / IronWorks Magazine giveaway by clicking here for details.

You can’t officially begin a bike project until you’ve got a place to hang all the bits and pieces. That, of course, means you must start with a frame, and that’s where Part 1 of our giveaway project bike begins. Like all of Brass Balls Bobbers’ frames, this essential foundation for our bike is made of hand-bent tubing that’s hand-fit and hand-welded by a team boasting years of experience at this sort of thing.

In fact, BBB’s frame production is managed by Sam Wills, a 3-time world champion in Top Fuel drag racing. Sam’s been building race bikes and street bikes for 30 years, so he knows a thing or three about frame geometry and material selection.

The accompanying photos and captions explain how each frame—in this case our giveaway bike’s frame—is made.

Beginning The Frame Building Process
Brass Balls CNC-machines all motor mounts, tranny plates, axle mounts and steering heads. All material used is either cold-finished flat stock or tubing. All tubes are precisely measured and bent by hand.

Frames Are Made of High-Content Carbon
All frame tubes are made of high-content carbon (for stronger welds) 1026 DOM (drawn over mandrel) mild steel with .156” wall thickness. The backbone is 1-1/2” diameter, all other tubing is 1”.

The frame tubes are notched for greater strength
The frame tubes are notched so the rear axle plates seat inside the tube before it is welded on both sides. This gives the frame greater strength, especially at the rigid tail section where torque is felt most.

Brass Balls Bobbers precisely measure all the dimensions
To assure accuracy and straightness, the crew at Brass Balls Bobbers precisely measure all the dimensions, including the axle plates as shown here.

Welding the steering head is a critical step
Welding the steering head is a critical step because correct steering geometry is so important to a bike’s handling performance. All parts are TIG welded by hand to assure complete heat penetration for strength.

Vehicle identification number (VIN), which is stamped into the frame.
We want you to be able to register and insure your bike, so like all Brass Balls bikes, this one will come with a vehicle identification number (VIN), which is stamped into the frame.

Weld joints are pieces of art.
We always appreciate quality workmanship. Here we get a close-up look at the weld joints of our giveaway bike. If there’s ever a case for “no paint,” this is it!

You can WIN this Brass Balls Bobbers / IronWorks Magazine giveaway by clicking here for details.

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