23 April 2010 - 8:18Something’s not Quite Round Here…
I had someone ask me the other day what was wrong with the chainring on Mr. Furley. See, I switched it from the sexy Boone Ti 32 tooth ring to something a little different. It was a gift from Mr Dejay Birtch. Another Fuzzy person told me that with this magical chainring I could go up a tooth in the front, and down one in the back, but it would still “feel” the same at the pedals. This means I can go from 32-20 to 33-19. What do these numbers mean? Well, 32-20 has a development of 145″, meaning for every revolution of the cranks (on level ground, perfect weather, no Stormtroopers etc), I travel a little over 12 feet. 33-19 has a development of 157″, which is over a foot more. See where this is going?
The new voodoo ring is none other than a Rotor. Notice how the chainring is not round. This is where the majick happens.
The shape of this ring is designed to keep your power on while you are in the transitional part of your pedal stroke, ie the “dead” spot, or, that split second before someone with good form goes from pulling to pushing on the pedals. The shape of the ring acts like a cam of sorts, with the teeth engaging the most amount of chain during the transition zone, thus keeping the power flowing to the rear wheel.
Poppycock you say? Hogwash? BS?
Well, I have become a believer. I’ve been riding this ring for a couple of weeks, and have been lucky enough to do some actual mountain bike riding to test this newfangled technology out. It works. I definitely feel the constant power at the pedals, almost like riding a fixie. It took me a while a while to get used to the feeling, as a single speed rider you sort of get accustomed to that dead spot and plan accordingly. I’m also feeling the extra gear, Fuzzy tricked me! But I have to say that in low speed super tech sections that require moves with pedal power, I was able to clean sections that would have otherwise stymied me, some of it was having a big assed gear, but a lot of it was having power no matter where my crank arms are.
Now wait, what’s this? Oval chainrings have been done before?
taken in my shop on a circa 198? Cannondale
True, but not like the Rotor ring. Some of you will remember Bio-Pace. This is not the same thing. The offset of the ring is almost the exact opposite of the Rotor, designed to pull the least amount of teeth so that the chain could shift from one chainring to the next. This was back in the days when dinosaurs ruled the earth, and there were no shift gates, or profiled chainrings, or other such technological marvels that increased shifting performance.
The Rotor thing is awesome, and I’ll be trying it out at Single-speed-apalooza in downstate NY this weekend. I’ll have a full report on the performance of this device next week. I’m also seriously considering running the new Michelin tires for the race, but I may switch out to the WTB Nanoraptor, still trying to figure that one out. Either way, there will be some good reading next week, when I will try to regain a normal posting schedule.
Have a great weekend and go RIDE!