I just build up a triathlon-bike and immediatly mounted Rotor Cranks on it. The problem is, instead of becoming faster, I´m significantly slower on this dreammachine than on my normal roadbike with clip on aerobar. I know to many parameters have been changed (seatangle (78 degrees), wheelsize, aerobar (Oval with barend shifters, Rotor cranks, ) to conclude anything, but I feel that the cranks are the sinners. Before I pull them of in frustration I would like to hear if I´m wrong about pointing at the Rotor cranks or if any of you experienced something similiar when just changing the cranks, not the whole bike?
How is your power on the bike? I could see how, if you are somewhat weak in the extensor power department, that you could become more easily tired with Rotors at first. They aren’t majic beans, you know. They provide a way to use your extensors more-so than regular cranks…so, if that is your weakness…bingo, it shows up with Rotors.
However, I know several people that were slower on their new tri-bikes for a while, until they got used to the position. THat could be it altogether.
I was immediately faster on the flats, hills took a bit longer for me to see an increase in speed on the Rotors. Anyone else have a WAG?
It involves a bit of work, but since you’ve obviously got the mechanical skills, why not stick the RCs on your roadbike for awhile? That will certainly help you determine if the cranks are the culprit. Otherwise, maybe you just need a bit more time to adapt to the new bike, position, etc.
That sounds like an easy thing to do. But, if you’re like me, you’d better get something to speed up the curing of the thread-lock. They make something, but I don’t know what it’s called. Anyway, mine kept slipping until I let it cure for 4 days. FINALLY, it was solid enough not to slip. That, plus, unless you’re really careful, you may end up having to “chase” the threads…especially when that threadlock is embedded so much.
If you are a true masher and don’t lift up much at all, the increaased speed of the rotors on the back stroke could actually increase the back pressure on the upstroke and slow you down (or keep you the same). Rotors will only make you faster if they improve the efficiency on the downstroke more than they reduce the efficiency on the backstroke.
Frank, does that mean that I would benefit from concentrating on smooth round pedaling to gain some effect? And how about high vs. low revolutions ? What suits them best?
I don’t know what your problem is so I am not sure what you should concentrate on, although, it seems to me that smooth round pedaling is always an advantage, even with RC’s, although some here would disagree with that statement.
I also suspect that RC’s are the same as all other cranks regarding cadence, there is an optimum and one should concentrate on trying to find the optimum cadence. Both too high and too low from optimum is bad, regardless of cranks used or pedaling style used. In my opinion, the more power you develop, the higher your optimum cadence will be.
kreutzer, Dr. Day is the inventor of PowerCranks. Without going into the differences between the two systems, suffice it to say that Dr. Day is more impressed with his product than Rotorcranks.
PowerCranks are a wonderful tool, I wouldn’t be nearly as good a runner if I didn’t use them. I think they made me a better biker, too.
Rotorcranks make your downstroke slower somewhere between 2 and 5 on the clockface. Some people think this is one of the reasons they work, when they work…because a slower rpm is more efficient to a certain point…but, go too slow, and you run into other problems. So, my guess is that you don’t really need to look at a slower rpm on Rotorcranks…since the power part of your stroke is already slower on Rotors. Although, some people report the opposite.
I can tell you PowerCranks proved to me that slower rpms (lets define slower…I used to pedal around 100, I found out I was faster in the mid-80’s) were better…BUT, once I got up to the 25 mph range, I found I had to increase my rpms a bit…which goes along with the idea of increasing rpms being needed at higher workloads. I find on regular cranks, my best speed is about mid-80 rpms. On Rotorcranks, that’s too slow…I find I have to be in the low 90’s, or my quads fatigue too quickly.
I think PowerCranks help my Rotorcranking, because I can get that faster-rising foot out of the way a little better than before I was PowerCrank trained. Dr. Coggan would disagree, stating that trying to remove any pressure from the rising crank more than you “normally do” is pointless. I simply don’t agree. One person’s “normal” is certainly not another’s, and, if you were like me, and actually seem to have learned to resist the upward moving crank in order to have a much smoother stroke, you could find that there is wasted power to be trained out of such a stroke. My “normal” wasn’t as productive as it could be.
If I were you, and wanting to keep Rotors on, I’d advise keeping the rpms up to your normal level.
I love it when people say that PowerCranks helped their running. Not much of a marketing strategy. “The cranks that made me run better”… not much for a catch phrase… but then again, I’m a sucker for (normal) cranks and normal (specific) training.
I love it when people say that PowerCranks helped their running. Not much of a marketing strategy. Are you kidding? If the goal is to market to triathletes, it’s a great strategy. Admittedly not such a great strategy for marketing to pure roadies.
SAC wrote: I love it when people say that PowerCranks helped their running. Not much of a marketing strategy.
Only thing is, I have no interest in marketing the things. I have no connection to PowerCranks. I’ve never met Dr. Day, nor talked to him on the phone, etc. I’m just an aging AG’er that trained on them, and I have no problem telling people what I think happened to my performances coinciding with PowerCrank training. My experience isn’t science. It’s simply what I experienced, as well as each and every one of the athletes coached by Sonni Dyer (you can look him up in the NC Series) that trained on PowerCranks (at least, that was true the last time I asked Coach Dyer about it)…not true for his non-PowerCrank athletes. But, it would be better to ask Coach Dyer, as his athlete’s results may have changed, I don’t know.
Wiley Joe wrote: Well, my head is telling me that the RC’s are taking advantage of the superior strength of my legs ability to push down on the pedal. AND they are making the upstroke more efficient because the hamstring, which is at a mechanical disadvantage and can’t produce as high of a peak power output, is able to spin at a higher instantaneous cadence which makes it easier to keep the power output level with that of the downstroke. The guy I bought the RC’s from, Gary T. doesn’t seem to see it that way, nor does anybody else I’ve spoken with, but…I believe it’s working.
Ah, Joe, don’t feel lonely, you do have another person that thinks this may be part of the benefits of Rotors! I wrote about this (the hamstrings being a quicker acting musculo-skeletal system due to their two-joint origin/insertion points, although not as strong as the quads) a couple of weeks ago. Slowing the quads in their best “power” area coinciding with speeding the rising foot through the upstroke with the hammies makes biomechanical sense to me on both sides of the stroke. Again, Dr. Coggan may disagree, and he has many more letters behind his name that backs up his opinion better than the letters I have behind my name. Still, that’s another of the reasons I think Rotors may be good for some people.
They aren’t majic, though. They require adequate strength in your extensors and/or a little different timing of your extensors, as well as your hamstrings/hip flexors. But, it sure didn’t take long for the timing differences to feel natural to me.
One last note, I started at one notch higher on the scale than recommended…because they slipped one notch the first two times I installed them, the last time they held tight and I just left it there. I immediately noticed a benefit on the flats and slight downhills. I didn’t notice a benefit in climbing at first, but, after 700 miles, the climbing difference is measurable (compared to regular cranks). I really like them. I still ride PowerCranks every week, too.
I’m off to set a new PR on Wednesday on Rotors at Lowe’s Motor Speedway…if any of you are out there, come over and say hi! I start at 6:35 or so. Ok, so I need someone to hold my bike at the starting line! Is that too much to ask?
Wiley wrote : “Frank, why DON’T you market those powercranks to runners?”
Uh? We do. And speedskaters, and XC skiers, and football players, and hockey players. So, we now have the NY Yankees, TB Bucanneers, SF 49’ers, TX Rangers, KC Royals, Univ of Arkansas Womens Track team, and others on them. A world class sprinter set a new american 100 meter record after 4 months on them. A world class speed skater is reporting .5 seconds off his hill repeats after 2 months on them. Bonnie blair’s husband who coaches speed skaters and hockey players is integrating them into his coaching practice. I can assure you these folks are not on them to become better cyclists. Each person should use them as best benefits them. For triathletes, the benefits, especially when one considers the run benefits, are pretty obvious.
Well, right on to both Yaqui and Frank! Yaqui, I think we don’t hear much about the hamstring issue we spoke about because the people selling and marketing the RC’s don’t mention this at all as far as I know. Frank, I guess when you don’t have the capital to advertise/market like you are Coke or McDonalds, or the president, it may seem that you aren’t marketing your product at all. Who set the American record in the sprints, I don’t recall any falling lately.
Aaron Thigpen. Set the American 35-39 record of 10.34 at the age of 38 (so he didn’t grow into it) at the Modesto Relays last year so I am told. You can visit his site or contact him at www.gamespeed.net.
Coke I am not.
The problem with both RC’s and PC’s is the reason for any benefit is pure supposition at the present time. some here would argue that whether there is any benefit to the devices is also pure supposition, but this question will be answered in time. Once this question is answered then the studies detailing the mechanism of improvement will also be done, assuming the benefits are real. One is starting soon I am told at Duke that will do both including gait analysis looking at the running improvement with PC’s in addition to looking at cycling improvement, trying to document there is improvement and looking at mechanism.
wiley wrote: “I think we don’t hear much about the hamstring issue we spoke about because the people selling and marketing the RC’s don’t mention this at all as far as I know”
Whether the hamstring explanation holds any water or not I am not sure but, as far as i can tell, the people marketing RC’s don’t really understand why the product works but have developed an intuitive explanation (“eliminating the dead spot”) that they use for marketing because most athletes don’t understand this stuff and that is something they will buy. Or, they do but don’t choose to use it in marketing because it would be too esoteric for the average user to comprehend.