I have been to the top of the mountain so now hear this: Griff can out climb me and Pat McLaughlin can apply some serious damn power in a sprint. Apparently I can do neither. Good times on the mountain last night and you were surely missed. Ended up doing seven five minute pieces of which Griff pretty much popped a wheelie all over my face. Humble pie for sure. Later, on the way home, we got all sprinty like with each other with McQuadlin unleashing some wickedness. The kind that make me fumble at the notion that I think I can ride my bike. Compared to that, I'm a dart player who occasionally gets out for a ride now and again. Ouch.
So lets get to today's technical question and answer period. Well, actually, less answer and more question. It breaks down like this, Griff has the full blown cockpit on his handlebars. Random watt meter, heart rate monitor, bone density scanner, the works. I ride with a HR monitor and cadence. Pat, who rowed at Davis during the days that they would chop down a tree, hollow it out, fashion some metal that they found laying around as riggers and get in and row the thing...rode with no data what so ever. I notice that during the pieces, when Griff would stand and pedal, I'd actually go faster and make up ground. My HR would remain the same as would my cadence (my only two reference points). Griff says that when standing, his power would remain the same as when he was seated. If the road variable remained constant (i.e. the pitch remained the same), shouldn't our speed remain the same? In other words, if the power remained the same, wouldn't the speed? If the random tabulator showed 350 watts either standing or sitting, isn't that still 350 watts? But each time he stood to maintain his watts, usually at the end of the piece, I would noticeably move up. I've notice this before when riding with others that when they stand, I actually pass them if I remain seated and seemingly they would slow. Any geeks...er I mean...fellow bike riders have any intel on this? McQuadlin, old school and all, rode while shaking his head at all the gadgetry. Hope you are well, Mr. Allknowing, and that you have the answers to the above.
Johnny GoFast
posted by Johnny GoFast at 9:48 AM
13 Comments:
JGF-
I received a text from McQuadlain this morning that stated, and I quote, "they crushed me." Well done. Please let me know next time when you plan to ride with him so I can race him home (after your intervals). This is now my only chance to keep up with him.
Jdub-you text message each other? Isn't that kind of poofterish?
Were you wearing matching spandex with said person yesterday? Whose calling who poofterish. And, anyways, I don't even know what poofterish is. But it doesn't sound manly by any stretch....
Professor Honeydew here. This should explain why you gain on Griff as he stands on the pedals: Efficient pedaling requires the effective transfer of energy from the lower limbs into the pedal. Consequently, this energy is transferred into the crankshaft, which drives the chain that accelerates the bike. Importantly, the effective use of force, through the pedal at the correct point in time of the crank cycle, is required. Anecdotally, this force is thought to be applied perpendicular to the pedal crankshaft during the down stroke. However, the foot is seldom perpendicular to the pedal crankshaft (Cavanagh et al 1986). Additionally, as the cyclist moves from the seated to the standing position, logic would dictate that the pedal � crankshaft angle will change and the range of the down stroke where maximum force is applied will also change. Finally, since the pedaling action is a cyclic activity then the recovery phase (upstroke) of cycling requires efficient use of energy through the inertial forces of the pedaling action (Cavanagh et al 1986). However, in standing these inertial forces change as the joint torque changes. Therefore, energy can be lost through incorrect pedaling angle resulting in reduced effective force.
-JV Circus
Dear JV,
Nice explanation but it is flawed. You’re talking about how Griff is wasting his effort through his thoroughly inefficient body movements. Having seen him ride, I can surely attest to that. However, the wattmeter is in the rear hub, way past where the energy is wasted. It reads the actual torque on the wheel.
My suspicion is that the wattmeter sample rate of the wheel torque is slow enough that it does not see the difference between an impulse-type pedal spin (out-of-the-saddle) and a smoother pedal spin (seated). If you where to integrate the area under the curve (torque to time) for the impulse spin vs. the smooth spin, there would be a significant difference. With the slow sample rate of the wattmeter, it just can see it.
Louis
Professor Honeydew here again: Louis you provide a lucid clear and technically looking argument. However, the question at hand is "how is it possible for Mundelius to gain on Griff when Griff stands up? Well, let me reiterate, the loss of inertia in the griffocoraptor is not from the body movements but the inefficiency in the pedal stroke as he is standing. The watt meter will take a rolling average of the power being generated; so as he is standing, the large force applied to the pedal on the down stroke is offset by the lack of power generated on the remaining pedal stroke. but the readout will be the same as if he was sitting and pedaling more efficiently. The loss of Griffs speed, i.e, mundelius gaining, can only be countered if
Griff increases his cadence or shifts to a higher mashing gear to maintain speed to offset the inefficient transfer of power in the standing position. For example, watching Alberto Contador and Michael Rasmussen in the mountains. Contador choses the standing position, but his cadence is clearly higher than Rasmussen's yet they are going roughly the same speed.
JV Circus
watts are watts however you produce them and have the same effect on speed - either JS increased his power or Griff's was not the same standing on average vs. seated. JS said his cadence did not change and hence power probably did not change much if the grade was the same, so maybe the inefficiency in Griff contributed to a lower avg. watts or the grade was in fact different.
Cda would have little effect if they were going uphill.
As an oft maligned target of this blog over the last 12 months, I thought I would take this moment to weigh in on the question. This is Griff. What is clearly evident to me after Tuesday's workout on Diablo is that all is right again in the natural order of things. I was ahead of JGF at the end of the intervals and that seems to me as it should be. Now this blog can return to it's original objective, i.e.: fantasysing and day dreaming about how to beat griff (excuse use of 3rd person). Just in time for CX season.
#1 379w, 4:52, 85c, 17.6mph
#2 375w, 4:57, 80c, 11.8mph
#3 377w, 4:52, 84c, 11.8mph
#4 357w, 4:52, 80c, 11.6mph
#5 350w, 4:52, 81c, 12.0mph
#6 352w, 4:52, 77c, 11.9mph
#7 347w, 4:57, 73c, 10.8mph
Up Northgate. HR at AT.
It would be competitive if I weighed 155lbs.
KP - nice #s
only problem is you guys went out too hard (last intervals dropping off in power)....
JD - too lazy to log on
Reading this string, Im having trouble figuring out which ones are cycling geeks, and which ones are cycling nerds. Maybe JGF's wifeage can weigh in the help sort you all out - if shes not too much of a dork to log onto a cycling blog.
JD, Had to go out hard cuz I was chasing the dudes riding old school style (no data).
Also noted that my overall average was up 6% doing intervals with my buds versus when I do them alone. Which tells me, I need to start doing intervals with my buds up here.
-Griff
Well, one down - Griffs is a geek. The gear, the lingo. Painful.
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