So, That's Why That Does That

Ever watch the front wheels of a shopping cart?  When you start pushing the cart, the front wheels spin around and point back toward you, automatically.  When you pull the cart backward, the wheels spin around toward the front of the cart, again in the opposite direction from the cart's movement.  It does so by design.  I don't know the science (nor am I nerdy enough to learn) but it makes it easier to steer the cart.

It turns out your bike does the same thing ... any bike ... at least any production bike in the last 100 years or so.  The fork and head tube angle are designed to put the front tire (where it contacts the ground) behind the steering axis (imaginary extension of the head tube), just as cart casters are offset so they can spin around in back of its pivot bolt.  The term is called trail which represents how far the front tire "trails" behind the steering axis .  Here's a pic:

You can find more information about trail on the web.  You can also find trail calculators and plenty of internet fights about the subject.  Have at it if that's your thing.

It turns out the Soma Wolverine has more trail than most bikes and considerably more than most road racing bikes.  Trail equates to stability, so the Wolverine has a very stable ride, especially at medium+ speeds.  Great for touring, too.  More trail also means more "wheel flop" (less derogatory than it sounds) where the front wheel wants to turn easily.  Less trail and less wheel flop equates to more responsiveness and maneuverability, giving road bikes that nimble feeling.

The Wolverine's long trail, and subsequent wheel flop, explains a few weird things I've noticed:

1) I've had trouble riding with no hands .. thought it was me and a weak sense of balance.  Turns out its the bike's wheel flop tenancies.  The wheel wants to turn with even a slight lean.

2) Adding a handlebar bag affects steering.  The bag's weight, even when only partly full, seems to amplify the floppiness.  So much, I've considered switching to a frame bag for touring.  Of note, the weight of front panniers doesn't seem to affect handling in the same way, perhaps due to the low mount points.  Front panniers on my bike also don't improve handling like some people report with their touring bikes.

3) I seem to have more confidence on downhills than others.  Stability at speed is what trail provides. I thought I was just braver.  I also have slightly less maneuverability than others in the corners, but that can be compensated for with riding technique.

4)  The bike feels a bit unwieldy at slow speed.  I'm used to it now, but I wrote about this after my inaugural ride on the bike. The Wolverine would not be a good choice for older people or anyone that consistently rides slowly.

Anyway, I now understand why my bike does some of the things it does.  Racing cyclists would call my bike sluggish, which is fine ... there are always tradeoffs.  My bike is more comfortable, durable and stable which meshes more with how/where/why I ride.