Trigger Happy

Lined up on the wire

[I’m always surprised by how many bicyclists aren’t aware that it’s possible to trigger a traffic signal with their bike, so I thought I’d re-post this article from the archives. —ed.]

There’s nothing more frustrating than getting stuck at an on-demand signal and having to wait for a car to come up from behind to trigger the light. In some jurisdictions, if you’re unable to trigger the light, it’s legal to proceed after stopping, but that doesn’t help when you’re at a cross street with heavy traffic moving in both directions. The good news is that in many cases it’s possible to trigger a light with your bicycle.

On-demand signals use what they call “induction loop vehicle detectors” to sense when a vehicle is waiting at a light. These detectors are essentially metal detectors embedded into the pavement. They work by sensing changes in an electromagnetic field and have nothing to do with the weight of the vehicle. You can often see evidence of loop detectors as lines cut into the road surface just behind the crosswalk. Wire sensors are embedded in these cut lines, and it’s possible to trigger a light by placing your bicycle wheels directly on top of one of the wires to disrupt the magnetic field. Some sensors seem to be more sensitive than others; in those cases where the light isn’t initially triggered, I’ve had some success by leaning my bike over toward the inside of the detector loop. In cases where there are two side-by-side loops, lining up over the center where the two loops meet doubles your chances of triggering the light.

Once I understood exactly how loop detectors work, my rate of success at triggering lights considerably improved; I’m currently getting somewhere approaching a 90% success rate at the lights in my area.

Any Excuse Will Do

Sometimes I wonder if we subconsciously “forget” items on our grocery list just so we have a reason to ride back to the store in the evening to catch the sunset. If I remember correctly, the excuse for the above evening’s ride was an onion for the following morning’s tofu scramble. You know what? Forget the excuses, a beautiful sunset is always worth a trip!

The Peak of Man’s Attainments

Double Parked

While quietly and effortlessly cruising along on our weekend errand run this morning, we agreed that there is no better, more pleasant, or more efficient way to move about on this planet than the bicycle. Then the following quote from Elizabeth West came to mind.

When man invented the bicycle he reached the peak of his attainments. Here was a machine of precision and balance for the convenience of man. And (unlike subsequent inventions for man’s convenience) the more he used it, the fitter his body became. Here, for once, was a product of man’s brain that was entirely beneficial to those who used it, and of no harm or irritation to others. Progress should have stopped when man invented the bicycle.

Did you know that a gallon of gasoline contains the equivalent of approximately 28,900 food calories? If a person could drink gasoline, they could ride approximately 722 miles on a gallon (assuming 40 calories per mile). Not bad for a vehicle that also provides so much (priceless) pure joy!

A Cool Tool for Bay Area Cyclists

SF BikeMapper

S.F. BikeMapper

Balanced Loads and Capacity for Grocery Hauling

Cargo Haulers

For everyday utility riding around town, I prefer a bike that can carry a pair of grocery bags in back and at least one up front. This allows me to carry a week’s worth of groceries on one bike if necessary (this is assuming a “normal” sized bike, not a cargo bike). A bike set-up for hauling this type of load will typically have a full-sized touring rack in the rear and some sort of basket or porteur rack up front. Alternatively, it could have a “lowrider” touring rack up front and a second set of smaller panniers. Besides providing extra capacity, having the ability to carry weight on the front of the bike balances the load between the front and rear, improving stability on most bikes.

People talk about the need for low trail geometry for carrying loads on the front fork, and perhaps for touring or randonneurring that’s true, but I haven’t found it necessary for utility riding. More important is a good center stand that holds the bike upright and steady when loading. A centering spring or strap to hold the wheel straight during loading is a good idea as well. When we’re talking about short trips to the grocery store, ease of loading and overall carrying capacity are more important than light steering for long days in the saddle.

If you’ve considered a porteur/front cargo rack for your grocery getter, but you’ve hesitated because your bike’s geometry isn’t optimized for carrying a front load, I’d encourage you to give it a try; personally I feel it’s a non-issue for the typically short distances most people travel for grocery shopping and errands. More important is a set-up that’s optimized for the loading process; once the bike is loaded and rolling, you’ll quickly adapt to the steering and you’ll be glad for the extra carrying capacity.

Royer Bridge

Royer Bridge

On the way home from Sunday morning coffee.

Reason Enough

Reason Enough

We talk about the health, financial, and ecological benefits of bike riding, but evenings like this are reason enough.

© 2011 EcoVelo™