Low-Slung Fun

When presented the opportunity to build a bike start to finish, I elected to put my theory that cyclocross bikes are built with too little BB drop to the test. I had theorized for some time that a bike that handled more like a traditional stage racing bike would be easier to lean through the tight turns of a cyclocross course.

So the $64,000 question is: How does it handle? My experience in riding the bike I built under Stanton's guidance has been that the greater-than-usual BB drop does help the bike corner better than other cyclocross bikes I have ridden. Cornering clearance has not been a problem. On broad, sweeping crit-style corners where I have seen other riders pedal through the whole of the corner, I have been able to pedal through as well. On the super-tight corners that I have only ever seen in cyclocross courses, corners where the course sometimes literally doubles back on itself is where my rig really excels. I have been able to corner much more aggressively than many other riders. Likewise, I’ve noticed in watching other categories race over the same course that the corners I coasted through were corners other racers coasted through as well.

While I expected the bike to corner well, there were two other, subtle, handling assets I didn’t anticipate. I noticed that in riding through frozen ruts, or any ruts for that matter, that I tended to be thrown off my line less than other riders around me. And on the opposite end of the spectrum (though I believe the handling issue to be related), on sandy stretches I was much more comfortable allowing the bike to slide and drift than I have been on any other ‘cross bike. Indeed, one of my favorite memories of riding this bike was in my district championship and and feeling the bike drift slightly while hammering under full power over sandy hardpack.

But don’t take my word for it. When Tim Rutledge, the former product manager for Redline first got the green light to introduce a Redline cyclocross frame and fork, he elected to design a bike that would handle like a traditional road bike when equipped with a 23mm clincher. He modeled the geometry after two bikes he saw reviewed in Bicycle Guide: an Eddy Merckx and Mario Cipollini’s custom Cannondale. Both were built around 7.5cm of BB drop. Rutledge has moved on to other pastures and Redline’s geometry has evolved to reflect that the company now offers complete road bikes, but Rutledge won a master’s national championship (as did several others) aboard the bike he designed.

The tragedy here is that no one truly understands the interplay of all aspects of bicycle geometry. By that I mean, there isn't an engineer out there who can explain in objective terms how each dimension relates to the others. We know in broad strokes how they relate, but as the previous comments have shown, there is some disagreement about what one truly experiences as bottom bracket height changes. Our use of terminology confuses the issue: Is a bike with a low bottom bracket (7.5cm of drop or more) more stable or more maneuverable? It comes down to how you think about bicycle handling. And while the specific differences in physics between how two-wheel and four-wheel vehicles handle are substantial, I do believe the differences in handling between a Mini Cooper and an SUV do help to illustrate the difference in sensation, because what is at stake is a matter of perception--if the rider or driver perceives confident handling, greater speed seems possible and not unreasonable.

While it is true that I could have shortened the bike’s trail or wheelbase, both those approaches have liabilities related to tire clearance and toe overlap that must be worked around. I think most builders would say that less trail will make a bike more responsive, but that isn’t the same thing as cornering easily and what I was looking for was a bike that I could lean without fighting, a bike that increased my sense of confidence when in a corner. I found a design that I like, no more no less. Ultimately, the question is why the industry continues to follow a convention based on a piece of equipment no longer used, a convention which can be validly questioned.