Like many dads who ride, Nathan Riddle was more than stoked for his kids to pick up the habit as well. We're starting to see more high end kids bikes hit the market, but Nathan decided to take matters into his own hands and make a titanium full-suspension bike for his youngest son, Zenyn. Riddle tackled the project head-on, building a frame on the same scale as his Santa Cruz Nomad, reducing it to kid proportions with 20" wheels.
The fork is a Manitou JUNIT fork with 120mm of travel, and the choice for his front suspension from the start. As far as rear suspension goes, finding a shock that will work for a 50lb human is tricky, so Nathan decided to use an older rear shock he had with a custom tune by Cascade Suspension works. The frame design uses a high leverage ratio to help the shock move under a lighter rider.
The frame has a titanium front triangle with a carbon / aluminum swingarm. Knowledge was pooled from several people including Ron Sutphin at United Bicycle, Mike DeSalvo, and John from Landshark Bicycles to help it come together. There's internal routing for the rear brake and Di2 wires and, of course, a water bottle mount inside the front triangle. Al in all, the frame weighs about 4.4lb and has around 120mm of travel.
Wheels are Sunringle Duoroc J-unit 20" rims, butted spokes, and boost hubs set up tubeless. Brakes are XTR M9000 with a light pull and short reach for small fingers. The rear caliper is a GRX flat mount because it lined up well with the design. Rear shifting is handled by XTR Di2, and yes, Nathan is aware that's a bit fancy for a kids' bike, but it was already on hand and provides a light shift action for small fingers. If crashing is commonplace, the Di2 may get swapped for something a little less fancy.
There's eccentric hardware on the shock and handlebar in order to allow for experimentation with geometry.
The complete bike weighs 22lbs. It's as proportionally correct as possible to a larger bike, although it's more of a 2/3 scale replica, since one of the challenges was getting chainstay length proportional to an adult bike, a task that proved nearly impossible to achieve and still have a functional drivetrain.