Rotor Q-Rings
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739 days
djrez4 posted 1 year ago.
How are you measuring pedalling efficiency?
Sounds like they made a significant difference for you...
-Dave
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UFTriGator posted 1 year ago.
If you ride on a CompuTrainer, it measures your power throughout the pedal stroke. If the power is perfectly constant, your pedal efficiency is 100%. Pedal efficiency with platform pedals is somewhere around 40%. It can also tell you exactly where your dead spot is and how bad it is, and how you balance your power between your legs.
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-Matt
Not fast enough.
115
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498 days
Sandman posted 1 year ago.
Shhhhhhhhhh! Don't let anyone else know about them. Tell everybody they suck.
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djrez4 posted 1 year ago.
UFTriGator;69954 wrote:
If you ride on a CompuTrainer, it measures your power throughout the pedal stroke. If the power is perfectly constant, your pedal efficiency is 100%. Pedal efficiency with platform pedals is somewhere around 40%. It can also tell you exactly where your dead spot is and how bad it is, and how you balance your power between your legs.
Neato! So then, you adjust the Q-rings to compensate for the dead spot in your stroke, right?
They make some funky cranks too.
-Dave
1089
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868 days
UFTriGator posted 1 year ago.
djrez4;69967 wrote:
Neato! So then, you adjust the Q-rings to compensate for the dead spot in your stroke, right?They make some funky cranks too.
That's exactly it. The cranks are cool, too, but they cost like a thousand bucks.
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-Matt
Not fast enough.
398
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1083 days
TBRAVO posted 1 year ago.
I thought about these before...interesting to hear from someone that has actually tried them. How did you adjust them for maximum performance based on your pedal stroke? Did you have a professional fitting done? Just curious as to how you get them setup correctly.
- T
1089
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868 days
UFTriGator posted 1 year ago.
Yeah...there's a sports medicine institute down the street from me and the guy there does free work for a few of us on the team from time to time. After warming up, I'd sit at base HR for 3 min to get an average power output and pedal stroke roundness. I did that twice for several different positions to make sure I was getting good numbers (I'm such an engineer :D). We looked at all the numbers and decided which position was best. All of them were better than circle chainrings, but some were more better.
The instructions tell you to set it up at the middle position and ride them for 400 miles, then start adjusting them from there. I just wanted something quicker and more concrete. I don't know if they would have worked as well if I had a good pedal stroke to start with, though.
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-Matt
Not fast enough.
398
Member
1083 days
TBRAVO posted 1 year ago.
Hmmm…interesting. So I guess the real question is whether it is better to use Q-Rings to fix the symptoms of a less than perfect pedal stroke OR just work on fixing your pedal stroke (if that’s possible) via coaching, use of Power Cranks, etc. Let us know how they work out in the long run, especially if your wattage or average MPH suddenly shoots through the roof. :D
1089
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868 days
UFTriGator posted 1 year ago.
I've been working on my pedal stroke doing one-leg drills and whatnot. My power definitely didn't go through the roof, but I got about 10W. I'm giving it a rough estimate of 30 sec saved on the bike and 20 sec saved on the run for an Olympic. (the run estimate being much rougher than the bike).
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-Matt
Not fast enough.
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572 days
OzTriGuy posted 1 year ago.
Hey Gator, i have been looking at these for a while. How do the gear changes go? Did you need to adjust the front derailuer (probaby spelt wrong) much?
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UFTriGator posted 1 year ago.
Yeah, but it's not very hard at all. If you don't know how to work on derailleurs, the front is the best place to start. It's one of the more intuitive parts of the bike to take apart and put back together. All I did was slide the derailleur up a little higher and change the position where the cable is clamped. Then I adjusted the limiting screws. All in all, less than 5 minutes for the derailleur...maybe another 10 to switch the chainrings. I'll tell you more in detail if you get stuck, but I think it's great to take bikes apart to figure what's going on. They're very simple once you understand what's happening, and you'll always have everything adjusted right for every ride and save money on tune-ups.
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-Matt
Not fast enough.
199
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583 days
Nobody posted 1 year ago.
Shimano had something similar to these way back in the 80s. I had 'em on my Miyata 912. They weren't adjustable, though....wonder why they phased 'em out.
Greatness is only achieved by those who perpetually raise the expectations of themselves to the point where it ruins their life.
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UFTriGator posted 1 year ago.
Shimano did them in the 80s and Specialized did them in the 90s with Biopace. I heard that both of them caused knee injuries. Hopefully the same thing doesn't happen to me. We'll see, I guess....
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-Matt
Not fast enough.
277
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739 days
djrez4 posted 1 year ago.
The Shimano rings were shaped differently. The wide section of the oval was placed in the dead spot of the pedal stroke instead of the power phase.
-Dave
I've been skeptical about these for a while. They seem like a great idea, but I figured that if they worked fantastically well everyone would have them. Anyway, I've had a couple guys that help me with my training say that they'd probably be a good idea (I have a masher's pedal stroke), so I bought them and decided that if they didn't work I could sell them on ebay for what I paid for them anyway. There's a pretty big lack of reviews of oval chainrings on the internet, so here's my contribution to cyberspace:
So I put them on earlier this week and just got back from having them tested this afternoon. (I figured on having a couple days to get used to them....they really only feel different if you pay close attention, so that was no big deal). The power numbers weren't incredibly impressive, but the increase in pedaling efficiency was good enough to warrant keeping the things. I tested them at base HR (~135). On circle chainrings I was pushing about 260W with a 60% pedaling efficiency. On oval chainrings I was pushing 270W with a pedaling efficiency of ~67%. Normally a good cyclist will have a pedal efficiency of around 70%, so I'm definitely a bit of a masher, which is why those guys recommended me getting the chainrings in the first place.
Anyway, I got a 4% increase in power (not huge, but significant I think), and a 12% increase in efficiency. I'm thinking that'll give me about 20-30 seconds over 40k on the bike (from the power increase) and then some improvement on the run (from the better efficiency, I just don't know how much time that's worth). The increase in the efficiency is what really impressed me about them, but I guess you have to have a bad pedal stroke to start with to get a significant improvement.
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-Matt
Not fast enough.