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View Full Version : Rotor Cranks - what do you know?



RoadRaven
04-26-2008, 10:58 PM
I am thinking about rotor cranks (NOT power cranks). My cadence is relatively slow, and I think my style of pedaling would suit this style of cranks...

Have any of you used them, or know someone who has used them/still uses them?

The cranks are offset (that is, when one pedal is down verticak to the ground, the top pedal is not quite opposite and instead of being vertical and pointing toward the sky, it has already begun the forward pedal stroke)

They are designed to remove the "dead spot"...

They are very expensive so I would need to try and pick up a second hand set... but just wondering what any of you know...

If you have no idea what I am talking about, go to this site...
www.rotorusa.com/
They are one of the biggest retailers and they have comprehensive explainations...

DebW
04-27-2008, 04:02 AM
There was some talk about these at UBI when someone asked about them. But I think they were talking about the Q-chainrings, not the Rotor crankset. The instructors said that the Q-rings are good and do help racers, but everyone has a different dead spot in their pedal stroke and it takes lots of experimentation to set up the Q-rings to match your own dead spot.

RoadRaven
04-28-2008, 02:45 AM
Thanks for replying Deb
Yeah, Q-rings are different to Rotor Cranks. Q-rings are elliptical rings designed to eliminate the "dead-spot". They are made by the same people who make RotorCranks though.

However... rotor cranks are off set cranks which work together to ensure that the top stroke is never in that dead zone...


I am trying to post a picture of them here... but here's an explaination while I battle dial-up!


To quote FAQs from the above site:
Simply put, the RS4X increase your bicycle's gearing, slowing the power/downstroke while reducing the gearing and speeding the recovery/upstroke. The action is very brief, and hardly noticeable in your first 20 minutes of pedaling, fading into a normal feel within the first 30 minutes of riding. This gearing change allows for the removal of the dead point, increasing the time that you are "pushing" down on the pedals, and reduces the physical demand on your body, lowering your lactate production. It also allows you to ride longer with less fatigue, climb easier, and reduce the stress on your knees.

RoadRaven
04-28-2008, 02:58 AM
Here tis...

7rider
04-28-2008, 07:33 AM
Interesting.
Would you envision these as a crankset on your training bike or your race bike? Is this an every-day riding tool, or is it geared more toward training to teach your legs to lose the dead spot?
As an aside, my DH is really interested in the PowerCranks, and will likely start looking for them 2nd hand on E-Bay.

RoadRaven
04-28-2008, 12:40 PM
Hey there 7

We (my partner and I) have heard of PowerCranks, but they have never appealed to either of us. With two cranks working independantly of each other, I keep imagining myself getting it completely wrong and ending up with both pedals at 6o'clock and just unable to pedal and falling over!!! :p

The RotorCranks can be adjusted depending on whether you are using them on the flat or over hilly courses. I would see myself using them on the flat - in time-trials. So they would go on myt dedicated time trial bike. I have a relatively slow cadence, so if I am doing a cadence of 70, thats 140 times EVERY minute I have to push through the "dead spot" at the top of the pedals using "normal" cranks.

Theoretically, if you eliminate the extra energy needed to get through that zone, you have a smoother more powerful stroke - and therefore are faster for little extra effort.

RotorCranks would probably suit me more than someone with a high cadence.

However, at nearly US$1000 for the ones in the above pic, I need to be sure of this experiment.

If I do try them, and I like them, I would also consider getting a second set (time to win the lottery!) for my road race bike, as I still struggle on hills and (again theoretically) RotorCranks shouls enable you to push a higher gear up a hill, which means you get to the top faster...

They are not about teaching your legs to lose the dead spot (that would be the idea behind PowerCranks).
RotorCranks are supposed to eliminate the dead spot altogether!

smilingcat
04-28-2008, 12:52 PM
I know of a gadget geek who tried it. This was when they first came out about 2, 3, 4?? years ago. I was :confused: :confused: Anyway, one of the bolts kept on working its way loose and the loose bolt managed to bang into the chain stay. It damaged the frame. He returned the cranks and got his money back. I don't know what became of the damaged carbon frame.

I'm just an old purist of sort. Hated the elliptical ring thingy back in the early 80's. Those made your pedal stroke worse not better and turned you into more of a pedal masher. And the cranks you are talking about adds all that extra weight and what do you get in return. Get rid of your deadpot?? pretty small thing for the very small added power and at what cost?

I think its best saved for those with lotsa money to burn and not much ability.

--------------more info -------------------
Did talk to the gadget geek. He said the cranks weighed a lot and he didn't think it was worth the weight. As for the damaged frame, it was a Kline not Calfi frame. He said his Kline frame was totaled because of it. He just got his money back for the cranks but nothing for his frame.

then again I'm just an mean old b**** :),

Smilingcat