Bronto Bikes is located in Springfield, Oregon, and create four models of steel-framed mountain bikes. Their handmade frames are pumped out at a rate of two per week in five stock sizes, unless you can convince them that you need custom geometry. Willy, my current test bike, is the 29er singlespeed model. Other offerings include Reverend – a geared 29er, Bon – a 26” hardtail, and Paycheck a 140mm, relaxed head tube, all-mountain hardtail.
Willy is built and TIG welded using True Temper OX Platinum tubing. Bronto custom bends the seat and chain stays in house and the frame is suspension corrected for a 80mm travel fork. My tester was built with a few options for performance and stiffness; the bent top tube provides additional stand over clearance, and the down tube and seat tube have sleeves for stiffness that are stronger than a gusset.
The rigid Udo Fork is also made by Bronto and features straight blade, chromoly tubes with hooded dropouts. It has a segmented fork crown and sleeves to add stiffness and reduce brake flex.
I’ve been pedaling the miles away with one speed from the 33×21 gearing, and after crashing over the handlebars on the maiden voyage and puncturing a Schwalbe Nobby Nic tire bad enough on the second ride that sealant and air spewed everywhere, Willy and I have relaxed into a respectful relationship. My size 20.5 tester has a 24.29” top tube that fits me comfortably. It has 71.5/74 head and seat tube angles, and shortish 17.3” chainstays.
Hive Chub front and rear hubs laced to a Stan’s ZTR Flow rim provide the rotation. I’ve already smacked the rear wheel so hard off a rock that the tire wouldn’t re-seal, yet the wheel remained true and dent-free. E. Thirteen provided the crankset and I’m liking the way they feel.
Willy rides quite stiff for steel and handles without shimmying in the turns or down fast straightaways. I like the way it climbs with seemingly no flex when I stand and mash up singletrack, and on the downhills I just hold on and try to ride light. The fork is really stiff too and was bone-jarring the first few times I landed after the wheels left the ground, but I’m used to it now.
I’m still playing around with the Cromag Fubars and haven’t found its sweet spot yet. I may swap it for an alt-bar. I’ve already swapped out the grips, because the Bronto branded ones have a smooth, tappered metal finish right where I need to wrap my thumb around for grip. On the trail I joked that thumbs are for monkeys, but it’s really hard to hang on when your thumbs are sliding around. Maybe it’s just me.
This is the second rigid singlespeed I’ve tested in the last year and it‘ll be interesting to compare how the Bronto differs, or not, from the Niner Air 9 Carbon that I rode and took to New Zealand for the Single Speed World Championships.
Look for the review to appear in Dirt Rag #159 and don’t forget to subscribe to the magazine to help keep this great content rolling your way.