Gear

e.13 answers a question nobody asked

 

e.13 has posted a press release today hyping their introduction of odd-sized guide rings. These rings (not surprisingly) are available in odd sizes, and you can take your pick of 33, 35, 37, and 39 teeth (compared to the more common ‘even-sized’ rings at 34, 36, 38, and 40 teeth). No doubt that these rings will uphold the great reputation that e.13 has built up for quality, durable chainrings.

The introduction of this ‘innovation’, however, begs the question of whether a 1 tooth difference in chainring size is really any difference at all. The claimed rationale is that riders stressing between a 36t and 38t ring on race day can find the perfect compromise in a 37t ring. However, if you’re running out of gears on a 36t ring, the jump to a 37t is going to help, but you could just as easily throw on a 38t and move up the cassette a little. There’s only a 2.7% gain in gear-inches going from a 36t to a 37t, and that translates into a difference of .3mph at 60rpm in a 13t cog (calculate it yourself here). The point of this number crunching is: if you’re spinning out a 36t, you can definitely handle a 38t on the course.

This isn’t to knock e.13’s choice to broaden the selection of chainrings, but if you already have a 36t and a 38t ring for race day, it’s probably not worth your cash or time to run out and pick up a 37t.

© 2008 Two Six Nation.