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916 NW 21st Avenue
Portland, Oregon 97209

503-222-2851

21st Avenue Bicycles specializes in road bike sales, service and repairs. Located in NW Portland, Oregon, the shop can help you find the perfect bike for your ride. Bike commuting, road biking, racing or the casual cruise. 

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Streetcar Track Science

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Despite all of our jokes, we take safety seriously here at 21st Avenue.  One of the biggest dangers facing cyclists in Portland (and especially right outside the shop) is the streetcar/MAX tracks.  These tire-eaters have claimed the lives of many front wheels and bruised countless egos over the years, and a few weeks back we decided we'd had enough of it!

Before we got down to our own tests, we looked back to Jan Heine's studies on the topic.  A well known (and very well-written) bicycle guy, Jan has covered the topic numerous times.  He finds that 42 mm tires are about ideal for crossing tracks (and urban cycling in general), but they can still get stuck.  Perhaps more important than tire size is the angle at which one crosses the tracks.  Jan prefers crossing at an angle between 20 and 70 degrees in an S-bend fashion when riding a bike with narrower tires.  Of course if the tracks are wet or the rider is forced to lean into this turn, all bets are off.

So if we put two and two together, a bike with tires larger than 42 mm and with a rubber compound better suited for wet weather should be about streetcar track proof.  Right?  Our crack team of mechanics set out to test this new hypothesis.

We started by actually measuring the inside of the tracks out here on NW Lovejoy.  The width at the top is 40 mm - narrower than Mr. Heine's preferred tire width, but it's easy to see how a low-pressure tire could squeeze in there.  Next, we took out a few bikes with tire widths we suspected might make the cut: A Salsa Fargo with 2.2" tires (a no brainer), a Marrakesh flat bar featuring Specialized Renegade 1.8" tires (about 47 mm) and a Specialized AWOL with 45 mm Fat Boys.

The 29er tires were a safe bet, but we figured at least one of the narrower options should work.  The 1.8" Renegades would hover just over the edges of the track valley, while the 45 mm Fat Boys could actually be wriggled into them.  The proof was in the pudding though, as our fearless crash test dummy Tim was able to ride parallel to the tracks and quickly/sketchily cross over without sending himself to the pavement.  While the tire is listed as 45 mm, it measures out to 43 on the stock AWOL wheels - looks like our friend Jan Heine's 42 mm 'sweet spot' theory holds up!

Of course we couldn't go to all this trouble without making a video for you:

And yes, we certainly do sell tires.