Rotor Q-Rings on Silvio

[laidback4HU]

Read HappyBentRider's brief mention about Rotor Q-Rings as an upgrade to his Silvio. Wondering if they have been added. WOndering about applying John Tolhurst's formula for positioning them for maximum efficiency for the rider. And am contemplating adding them to my yet to arrive Silvio, too.
Am happy to hear from anyone who has worked with the elliptical chainrings.
Laidback4HU

 

[John Tolhurst]

Maria Parker uses Q-rings on

Maria Parker uses Q-rings on both her Silvio and Vendetta. That is a pretty strong endorsement.

 

[gannet]

I'm keen to try these too.

I'm keen to try these too. Seems hard to find a full range, ie just to match a normal road tripple ( 52 39 30 ) It's like they make them for serious racers only, road or dirt. And the BCD's don't match too easilly.
A bit of research showed that Stronglight ( an old favourite of mine ) have a line called Bio Concept. I understand the 'ovality' is similar (or the same?) . Certainly a better price. I have some on order anyway, and will let you know how they go.

 

[John Tolhurst]

Hi gannet, 
I've done a lot

Hi gannet,

I've done a lot of work studying elliptical rings and how & why they work. The key is timing the major axis to pick up the chain at the right moment of the leg strong. Without adjustment holes, I doubt you will be able to get the timing right, it is very sensitive, certainly you need at least 12 degree steps.

The examples I could see on line had five holes for bolting to the spider. I would not be able to adjust these properly to a cruzbike, without a lot of luck.

 

[NoCruzbike]

Elliptical chainrings/Q Rings

http://www.ncbi.nlm.nih.gov/pubmed/21266731

A study on the elliptical chainrings. For what it's worth. From The International Journal of Sports Physiology and Performance, Dec/2010

Also from Triathlon Magazine/Canada: http://triathlonmagazine.ca/2010/03/sections/training/bike/pedal-power-do-elliptical-chainrings-really-work/

"In addition to my own experience, a long time friend and California State University Bakersfield professor, Jeff Moffit (Ed.D.) did a study on the effect of Q-Rings on cycling economy.

Subjects completed a 30 km time trial, with data recorded at the 10km and 20km marks and at the finish. The study found no conclusive performance advantage to using Q-Rings, but also that there was no disadvantage over longer distances either.

The bottom line is that there is no such thing as free energy. By having more time spent in the power phase, the muscles will be limited by the build-up of lactic acid. Some studies have shown that there are potential benefits from Q-Rings during anaerobic efforts of 30 seconds or less. These benefits are not applicable to triathletes, however, as these anaerobic efforts simply do not occur during a triathlon bike leg."

 

[defjack]

(No subject)

 

[defjack]

 Heres how my Silvio is setup

Heres how my Silvio is setup 153 cranks ,52,40 and 30 Q rings.Works ok for me. Plus 100 mm chain stay extension. Works great for me. Jack