By Ed Pavelka
Product: 50/36-tooth 110-BCD alloy chainrings
Weight: 115g (50), 40g (36)
Source: Rotor website, other websites
Warranty: 2 years
RBR advertiser: yes
How obtained: sample from company
Tested: 3,397 miles (5,470 km)
Are they better or are they just different?
After some 220 hours on Q-Rings, my answer is yes. Compared to round chainrings, Q-Rings are certainly different and I think they’ve made my pedaling better.
How much better is tough to say. And believe me, I’ve thought about it during lots of rides on my hilly southeastern Pennsylvania roads. Unfortunately, the testing has been in cold winter weather with me bundled up like the Michelin man. Not the conditions in which improvements in speed or power are very noticeable.
My first ride with Q-Rings was a 44-miler on November 19. Their unique, non-round shape felt different to legs that had turned nothing but circular rings for 33 years. But not as different as I expected.
After that ride I had no leg soreness or anything else unusual. So five days later I did something that’s certainly not recommended for a second ride on new pedal-stroke-altering equipment and went for 129 miles. The course that day had 6,700 vertical feet and my average speed of 17.4 mph was about 1-1.5 mph faster than normal for late November. Hmmm . . . .
How They Work
Q-Rings are not a copy of Shimano’s ill-fated Biopace chainrings of the 1980s. Nor are they radically elliptical or oval like the old Durham rings or the recent incarnation from Osymetric (the brand that Team CSC’s Bobby Julich uses).
When Q-Rings turn they have two low and high points in each revolution. These coincide with a rider’s foot position at the top and bottom “dead spot” of the pedal stroke and with the power portion from about 2 to 5 o’clock. The idea is to reduce the effective chainring size where power isn’t applied and increase the effective size where legs naturally push with greatest force.
For example, if you normally use a 53-tooth large chainring, a Q-Ring turns it into a 56 during each stroke’s power phase. But through the dead spots it’s reduced to the equivalent of 51 teeth. For this test I used the 50/36-tooth compact setup with corresponding gear increases and decreases.
The changes are subtle and my legs don’t feel them at 90+ rpm whether I’m spinning or pushing. Where I notice a benefit is on seated climbs in the 36-tooth ring at a slower cadence around 80 rpm. I can feel my feet coming over the top with greater smoothness. The sensation is hard to describe — it just feels like an improvement. At least it did during early rides. But then, as more miles went by, I lost the sense that Q-Rings weren’t round rings.
So am I really getting a benefit? We’re back to the basic question — better or just different?
Science Behind the Shape
Q-Rings are made in Spain by the same company that produces the Rotor crankset with its variable crankarm position. The crank is designed to eliminate the dead spots; these rings attempt to reduce them. (Rotor crankset rings are conventionally round.)
Obviously a good deal of engineering has gone into Q-Rings (patent pending). The company provides engineering studies that describe the precision of the shape and lab studies that show benefits. Each ring can be installed in many different positions relative to the pedal stroke. But five bolt holes are marked with 1-5 dots to indicate the positions most riders will find most beneficial. New users are advised to start with each ring at No. 3 and then experiment with other orientations after they’ve adapted.
The Rotor website has advice on chainring positions and other technical information. It tells how to test yourself to determine which orientation is optimum. Among the advice: “When deciding between two consecutive settings (i.e. 2 and 3, or 3 and 4) the lower number will give you more speed and the larger one will allow for faster acceleration.”
Changing the orientation is easy — just unscrew the fixing bolts and rotate the rings (no need to remove the crankarm). But unless you have a heart monitor and/or power meter, the difference between any two settings will be pretty subjective. You can tweak to your heart’s content, even setting each ring on a different number. So far I’ve kept both rings in position 3 because I’m not sure what I’d be looking for by making a change.
If you do have a means of measuring your performance, Rotor says you’ll find these physiological advantages of Q-Rings:
- An average 4.1% increase in power. By increasing the gear size when your legs are in position to produce the most power, your muscles are used more efficiently. Rotor says a recreational cyclist will see a larger power gain than someone at an elite fitness level.
- An average 9.1% decrease in lactate levels. Rotor contends that lactic acid buildup occurs because hamstrings and quadriceps are disengaged at the dead spots while smaller knee muscles and tendons are engaged. This on/off cycle is not as pronounced on Q-Rings because they speed you through the dead spots, keeping the hamstrings and quadriceps engaged longer around the pedal stroke.
- Quicker recovery. Rotor’s theory is that lactic acid buildup can prolong recovery time, so the less produced by pedaling, the better. The benefit is less fatigue during the current ride and on tomorrow’s ride.
- Less knee stress. This is said to result from Q-Rings reducing use of knee tendons throughout the pedal stroke.
Knee stress interests me because I’ve had three surgeries related to cartilage damage and associated wear in my left knee. I’m riding on borrowed time, so I’m usually not one to take risks with equipment that messes with my pedal stroke. In fact, when the Q-Rings arrived I was undergoing a series of injections with a drug intended to improve the viscosity of knee fluid. So the rings sat on a shelf for three months. I kept procrastinating.
But I also kept reading about road, MTB and cyclocross riders having success on Q-Rings. One is Dutch cyclist Marianne Voss. She started using Q-Rings in late 2005 and the next year won the world road championship, the world cyclocross championship and European U-23 road championship. She calls Q-Rings her “little secret.”
In checking online websites and forums, I found a number of other success stories and personal perspectives. Examples:
- “I made the change to Q-Rings because it just makes sense. No matter how well adapted to pedaling circles we can become, there is no getting around the inherent weaknesses of the pedal stroke. Q-Rings do not eliminate the dead spots, but they do lighten the load for the weaker areas and transfer that load to the stronger muscles.”
- “With Q-Rings the pedal stroke remains circular. It is only the rings that are elliptical. This is one reason why the system is an excellent one for trained athletes. The biomechanics do not effectively change, only the load-bearing profile of the pedal stroke changes.”
A cyclist and coach named Richard Wharton reported that he tested Q-Rings on a CompuTrainer and found:
- In a 5-second sprint he reached 1,279 watts with Q-Rings vs. 1,125 watts with round rings, a 13.6% improvement.
- In a 1-minute test, he averaged 480 watts with Q-Rings vs. 400 watts with round rings, a 20% improvement.
I read other positive personal experiences and very few negative comments. It seems that Q-Rings are winning converts and their popularity is growing. I decided to put them on.
Q-rings are easy to install. You don’t even need to remove the right crankarm. Just unbolt the round rings and slip the unround rings into place, being careful to note the numbered orientation of each one. As mentioned, starting with both in the No. 3 position on the appropriate crank spider arm (illustrated directions included) is recommended.
Next you need to relocate the front derailleur. Keep the outside edge of the cage in line with the big ring, then reset the height so the bottom of the cage is 1-2 mm above the tallest teeth of the rotation. This leaves a gap of about 7 mm to the lowest teeth. When you see this you might think front shifting will be a disaster, but it’s practically as good as with round rings. Most upshifts are clean and noiseless thanks to chain pickup pins effectively placed on the inner face of the large ring. Shifts to the small ring are just as good. Rotating one or both rings to different positions doesn’t affect front derailleur setup.
While pedaling you can glance down and see the chainrings bobbing. The amount looks significant but it doesn’t affect anything else in the drivetrain. The rear derailleur cage barely moves in response to the out-of-round rings turning the chain.
Q-Rings are available in sets for road double cranks, road triple, mountain bike and cyclocross, and as single rings that can be mixed with round ones. The many choices and various bolt circle diameters are described and priced on the Rotor website.
So far, all good. But if you’re thinking about installing a set of Q-Rings you’ll be out of luck with certain cranksets. For example, the outer compact 50-tooth ring (110 bolt circle diameter) does not fit Shimano compact cranks or 2004-2006 Campagnolo compact cranks. However, the inner 36T will fit all compact models.
Q-Ring technology isn’t cheap. My 50/36 compact pair retails for $199 — the least expensive set available. In comparison, a Shimano FC-R700 compact crankset (arms as well as rings) costs $250. Individual Q-Rings range from $42 to $155.
Despite the cost and high-quality appearance, two of the four 50-tooth Q-Rings I’ve now used were not true. One had minor lateral wobbles while another was worse. Rotor people expressed surprise and said they’d take it up with the factory. They said they hadn’t heard of crooked rings from any other user and mine might have been bent in shipping. But the box showed no signs of damage.
How was I able to check additional rings? Because I bought extra sets of Q-Rings to go with the sample I was testing. I liked the feel of Q-Rings on the first ride and figured that to get the full impression I should have them on all the bikes I ride regularly. In retrospect, it wasn’t necessary. After riding Q-Rings for hundreds of miles and then getting on my round-ring trainer bike or tandem, I couldn’t feel the difference. I didn’t need to readapt. Lately I’ve been switching back and forth between round and Q regularly, and even riding both shapes on the same day. No difference.
Or maybe my legs can’t sense it but my performance will reflect it. I am sure of one thing: My left knee hasn’t felt as good in several years as it has in the last 700 miles on Q-Rings. The improvement wasn’t immediate — it took more than 2,000 miles — but I’m thinking the rings have had something to do with it.
My three main bikes are now Q-Ringed, so let’s see how my power, lactate levels, recovery and knees do in a season full of long miles and endurance events. I haven’t found a downside to Q-Rings other than the cost. My hunch is that there’s an upside.
Thanks for this, Ed.
How does your left knee feel now after more time on Q Rings? Any dropped chains?
Martin meades says
Good evening Ed, good reading your post. I have just bought a pair of q rings for my winter bike. I have nearve damage to the lower left leg from back surgery and have foot drop where as my cadence increases the power drops down. My srm power meter shows 70/30 in favor of my right leg at 95rpm or more. So this will be interesting to see if these could help. I also have the luxury of srm torque analysis from my club. Thanks again Martin.