I'd expect Jan is exactly right here, even though I do not have the experience to directly compare.
On a long event, total time should be affected significantly by small repeated delays such as the time it takes to regain momentum after a troublesome shift. If a particular hardware set supports his reliable and consistent style better than another, it will be faster for him. If you shift 200 times in a brevet and lose a comparative and seemingly imperceptible half-second per, that's an effect of 1 2/3 minutes over that event. I don't know how closely randonneurs watch the clock, but my bud who does marathon running would be ecstatic to get 100 seconds for free.
If you also consider it might take 10s of seconds to regain lost momentum, the penalty can be significantly worse.
It's a game of continous and predictable power output, not of sudden bursts of energy, like club riding can be.
I like threads where I learn something, and this is a good one IMHO!!
Ken Freeman Ann Arbor, MI USA
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From: Tom Dalton [mailto:tom_s_dalton@yahoo.com] Sent: Thursday, December 06, 2007 1:09 PM To: Jan Heine; Kenneth Freeman Cc: classicrendezvous@bikelist.org Subject: RE: [CR]Re: Friction shifting and ramped cassettes
Jan,
Just for the record, my post that you cite below was sent to you and another member, but not the list because it was entirely off topic (as opposed to partly off topic like most of my posts).
You said: If I turn the pedals over slowly for just 2 seconds on a 10% slope, I lose a lot of speed.
I'm don't think I'm really talking about that much time. What I was pointing out is that you don't need to drop the chain from cog to cog, engaging each gear along the way. You click fast and softpedal for a revolution or so, and the chain lands where you want it. As fast as Ergo? I have no idea. I'd have to ride Ergo and STI and compare... that would be the relevant comparison.
You said: An on-topic bike with friction shifting, ridden well, should be faster over rolling terrain - such as we see a lot around here in western Washington - than a bike with STI. (Oh no, now I've thrown down the gauntlet, and this thread never will die!)
Well, that's ceratinly provocative because on its face it is so absurd. I can only begin to consider that this might be true if I were to narrow the definintion of "rolling" to include only terrain where out of the saddle pedaling is not required, and all the upslopes can be taken in a single gear. Perhaps you have so throughly adopted to downtube friction (and it's limitations) that your natural pattern is to select a single gear for each upslope. If you want to make mulitiple shifts along one upslope (as you loose momentum, for example) reaching down again and again is a serious disadvantage relative to either Ergo or STI. If you need to stand, it gets a lot more burdensome to have downtube shifters rather than Ergo/STI. To me you assertion has the tone of wishful thinking. As I was saying earlier, we all like to think that our hard won skills confer some performance advantage, and in many instances they inarguably do, but I think it is wildly overreaching to assert that, given enough skill, downtube friction is a faster system over rolling terrain.
In the big picture, you are clearly a more experienced rider than I, particularly with randonneuring, so maybe I just don't know what I'm talking about. But, in the rolling terrain around here I have experienced considerable disadvantge with downtube shifters, even when indexed, on fast group rides (where everyone else uses STI or Ergo, of course). Tom Dalton Bethlehem PA USA
Jan Heine <heine94@earthlink.net> wrote:
At 6:53 AM -0800 12/6/07, Tom Dalton wrote:
>Ergo allows upshifting (moving to smaller cogs) several gears in one
>sweep. You push down on that thumb paddle by as many clicks as the
>number of cog positions you want to move through. With STI you need
>to press the smaller lever one time for each upshift you want. Jan
>was saying that when he drops from the large to small ring up front,
>getting to the next lower gear requires upshfiting three or four
>cogs, and that having to push the STI upshift lever, and wait for
>the shift, repeated three or four times, is inefficient.
> I use STI and it is my experience that you can click the upshift
>lever 3-4 times very quickly, while turning the pedals over very
>slowly, and run the chain directly to the 3rd or 4th cog up the
>freewheel. Ergo may be quicker, I don't know, but I don't think you
>need to engage each cog along the way as you upshift by several
>gears on STI.
If I turn the pedals over slowly for just 2 seconds on a 10% slope, I lose a lot of speed. The alternative is shifting to the small ring _before_ I reach the hill, but that means that I don't enter the hill as fast as I should.
As was pointed out in the "Randonneuring Basics" series, your speed over rolling terrain very much depends on maintaining momentum, and STI makes that difficult.
OT content: An on-topic bike with friction shifting, ridden well, should be faster over rolling terrain - such as we see a lot around here in western Washington - than a bike with STI. (Oh no, now I've thrown down the gauntlet, and this thread never will die!)
Jan Heine Editor Bicycle Quarterly 140 Lakeside Ave #C Seattle WA 98122 http://www.bikequarterly.com
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