Prototype Steel Mountain Bike

Mountain bike geometry is crazy. I am not going to say that road bikes have stayed exactly the same forever, but for the most part they have. For me it is funny to think how few things have changed in bicycles over the last hundred years yet we find ourselves with new trends that seem to break through some barrier of design. This bike is on the bleeding edge of the latest “forward geometry” trend that has been “pioneered” by some kooky bike designers over in the UK. To me this geometry makes sense, and while I haven’t gone all out in the past I have put these principles into use on my frames since the get go.

Forward geometry places the rider, you guessed it, further forward. I think of bike geometry as a several contact points. You have your wheels, the only two points that contact the ground, then you have where your hands go, your feet and finally your butt. Where you place these points in space determines how the bike handles, then you get to determine how to connect those dots. With this design I started with the front center distance that I thought would “perfectly” distribute my weight between the wheels, a normally unheard of 830mm. Then to put my handlebars in the correct position I moved the headtube back to 66.5 degrees with one hundred and twenty something millimeters of trail. Between the front center and trail we are going to have a really stable handling bike, so we shorten the stem as short as we can go to decrease the steering axis. This eliminates wheel flop and allows the bike to not handle like a totally dead fish. To keep the reach in check the seat tube gets brought up to 74 degrees, which is on the steep side, but conveniently, on the modern MTB you are either in your climbing position or your dropper is down. This works out nicely. A short chain stay keeps the overall wheelbase in check, A lower bottom bracket makes rear wheel steering through corners fun.

Yeah. That is how we got here. Make sense?

Anyhow, lots of ideas look good on paper, I am looking forward to testing these in the field. Later this year I will be releasing some stock geometry mountain bikes (think built to order) and this is the prototype for that, I really think this could be the one.

Thanks for reading, let me know if you have any thoughts or questions on this stuff in the comments.

-Adam