Industry Interview: Christie O’Hara from Rotor

Rotor's Q-Rings minimize the dead spot in your pedal stroke, increasing your efficiency on the bike.

We recently had the good fortune to have Christie O’Hara from Rotor come by and tell us a little more about what’s going on at Rotor and some of the science behind the Q-Rings. The interview is somewhat paraphrased to make it readable but the information is the same. Enjoy.

1. What’s the history of Rotor and what makes Rotor rings different from BioPace or other non-circular designs?

            “In 1995 two aerospace engineers in Madrid worked on the original Rotor cranks. Rotor as a company was founded in 1999. The cranks were offset to eliminate the dead spot. The problem was that they were too heavy, so no one wanted to use them in competition. In 2005 Q-Rings were released to accomplish the same goal yet be light enough so that pros wouldn’t shy away from them. Pedal stroke analysis shows that maximum torque isn’t produced at 90 degrees [with the pedals perpendicular to the ground] but just after [on average around 108 degrees]. By increasing the chainring size at the point of maximum torque, and decreasing it at the very top and bottom of the pedal stroke, Q-Rings decrease the amount of time spent in the dead spot. Biopace had the right idea, but the wrong orientation. Biopace puts the largest part of the chainring at the dead spot of the pedal stroke, which it turns out causes knee problem and that’s why it was taken off the market. The engineering just wasn’t there.  Bradley Wiggins rides with O-Symmetric rings, which have a flat spot and then ramp up. These rings have much greater ovality than Q-Rings which isn’t a bad thing. However, they aren’t engineered well so the shifting is terrible. Chris Froome also uses them and will attest to that.

An easy way to think about Rotor rings is that you’re pushing a bigger gear on your downstroke, a 56 instead of a 53 [if you’re running a standard setup]. Your chainring velocity is slower at that point because you’re pushing a bigger gear. Because you’re going through that portion slower it allows your muscles to fully activate at the right time. With a regular round ring, by the time your muscles are activated you’ve already pushed through the power zone and are moving through the dead spot.  So a bigger portion of the chainring in the power zone allows your muscles to fully activate and produces more positive work and less negative work. At top dead center [absolute highest part of the pedal stroke] you can’t create any power, so it’s considered negative work. Since on a rotor ring that portion is smaller than a standard round ring, you spend less time in the dead spot and therefore are producing less negative work.”

2. What can riders expect to feel when trying Q-Rings for the first time?

“Some people don’t feel any difference when riding Q-Rings. It just feels natural. Some people feel a huge difference. When it feels normal, it’s a sign that the rings are in the right position.”

3. Is there an adjustment period?

“Yes there is an adjustment period, however it’s very quick. You are not using different muscles, your muscles are neuro-muscularly firing differently. Generally, you should be adapted by a week of riding. You have to mentally realize you’re pedaling a different shape, but many people feel that the rings are more natural feeling than standard rings, so for some people the adaptation process takes almost no time at all. Your muscles will adapt to it pretty quick.”

4. With all the adjustments available with Q-Rings, how can a customer set-up their Q-Rings and know they are getting the maximum benefit?

“We start everyone including our Pro riders on position 3, the neutral setting, which is the middle position (108 degrees). There is also a Setup Guide online that you can reference. It has nearly every sensation you could possibly feel after installing the Q-Rings.  Generally, if something doesn’t feel right, then you simply need to move the ring position one slot. For example, if you want to feel the resistance a little earlier, you would move the rings to position 4. If you want to have the resistance a little later in your pedal stroke, you would move the rings to 2. One thing that’s not uncommon is to have different positions in your inner ring and your outer ring.”

5. What Pros are currently riding Q-Rings?

“We have Garmin Barracuda as our biggest team. We also sponsor Suar Sojason. Jerome Coppel is their best rider. Jonathan Hivert, Ryder HesjedalTyler Farrar, Robbie Hunter, Coldo Fernandez, Murilo Fisher, Alex Rasmussen, Johan Van Summeren and Heinrich Haussler are all riding Q-Rings. The riders aren’t forced to ride the Q-Rings, however the Sports Scientist at Garmin is trying to get them all on the rings. Currently, Dave Zabriski is not riding Q-Rings because he’s attempting to do everything how he had it in the 2008 season. Since he wasn’t riding Q-Rings at that  point in his career, they aren’t on his bike currently. It’s really unfortunate because time trails and triathlons are where Q-Rings can reap the greatest benefit because the athlete is virtually in one position the entire time.”

6. Are there any exciting projects on the horizon that you can share with us?

“There is a new TT spider that will have an alternative bolt hole placement. Normal Rotor spiders have the holes positioned so the rider experiences the largest part of the chainring at 108 degrees with the other holes at + or – 5 degrees. The TT spider will offset those positions by 2.5 degrees. We are also releasing a Rotor Powermeter. It will have the strain gauges placed in the 3 holes of the Trinity drilling of the 3D+ cranks. It will have strain gauges in both arms so you’ll be able to measure both legs independently. For the first release it will use a CR 2032 battery that will be easily accessible similar to Quarq. We also have something really big coming out in the fall, but I can’t tell you about it.”

2012-05-15T09:01:54-08:00