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Par for the course for The
Par for the course for The Guardian. Top-notch reporting let down, as usual, by the constructivist editing and editorializing. The last four paragraphs (that were likely segued onto page 62D) hint at the real story:Mario, a San Francisco user of the bike-share program, who has a discounted membership because he qualifies for food stamps, said he was perplexed by the backlash.“It’s the cheapest transportation option we have,” said the 29-year-old, who works as an administrative assistant and asked not to use his full name, because he feared backlash from anti-gentrification activists.
The vandalism is “hurting people that actually use this”, he added. “It just makes us in the neighborhood kind of look childish if we start burning and graffiting everything. I think it’s really sad, because a lot of people depend on these bikes.”
Activists shouldn’t be worried about the bikes drawing wealthy tech workers to the neighborhood, Mario added: “The people who have money are just going to take an Uber.”
I’m 1.86 and 97kg and XL
I’m 1.86 and 97kg and XL Garneau bibs are good fit, if a smidge loose for my liking. So I doubt XXL ones would work for you.That’s not tale of woe, IMHO.
That’s not tale of woe, IMHO. A 13% HC climb that starts easy and ends easy means that the through of it was likely around 15%. That’s as hard as it gets on a road bike. Pros weren’t regularly doing climbs thay hard until 10-speeds and compacts were invented. Not only did you have a go, but you crested it. Chapeau.But as has been mentioned, you were more than likely undergeared. Yep, you can train pushing lower cadences. But climbs like that are why pros use compacts and 32 cassettes, never mind us mere mortals. 34-32 is 22% easier than 36-28. That’s huge.
I just rode this weekend with a much fitter friend up a 13% gradient with that same gearing difference and he cracked while I was almost-but-not-quite-at my limit. He proceded to destroy my PB by nearly 2 mins on the next (7%) climb. He’s more of a spinner than me, so even though he’s probably around 10% fitter he likely couldn’t even match my lowest sustainable cadence, much less go 10% lower than that, for more than a few minutes. Which was precisely what happened. Gear ratios are a thing for a reason.
This annoys me to no end. If
This annoys me to no end. If you’re in a chaingang or a race the onus is on you not to deviate, sure. But if you’re in open traffic follow the rules of the road and overtake with care. Maybe not 1.5 metres, but unless you are overtaking a group, why not give at least three feet?I once had a pro pass me on the inside as I was retaking my position afer passing a girl on a beach cruiser (who he must have also passed on the inside) on a very wide closed road. He had the nerve to mutter something back to me. I sprinted beside him and told him off. It’s amazing how quiet people can get all of a sudden.
Following in the same vein as
Following in the same vein as previous commenters, on the steeper hills I’m faster on my XC bike than my road bike because of the gearing. Even 34-32 isn’t enough to “comfortably” lug my 220lb frame up a 15% grade. On anything between 5-15% it’s mostly weight (unless you can truly acquit yourself uphill) that does the trick. Road bike vs hybrid will be mostly down to the scales. So I wouldn’t be surprised on similar times on a fairly hilly course, or even faster times on a particularly punchy affair.
Outside of that, I also agree that repeatably faster is a bit weird. And on the flat the road bike should be noticeably faster than the more upright commuter, unless you’re commuting into Roubaix. Comfort, crank length, tyres are all worth looking at, but that should really all be marginal. Anything bad enough on bike fit and position to have that kind of an impact should really be felt or, especially, seen by a bike fitter.
So I’d guess a combination of fitness and mechanical issues. Maybe you’ve gotten fitter and the mechanical issues on your bike have masked it. I did a couple of shockingly slow times up a climb early in the year, some of which was lack of fitness, but most of which was tyre rub due to a faulty skewer.
I’d consider keeping the Defy
I’d consider keeping the Defy as the commute/winter bike and getting a dedicated ride for sport.
I’ve yet to pull the trigger on upgrading my Defy. It was to be a Gt Grade, then a BMC Gran Fondo, then a Cervelo C3, now a Focus Paralane.
Chrs. Looking at it from a physics point of view, regardless of speeds attained, at the end of the day you are getting rid of the same amount of potential energy (from top of the hill to bottom) so it would seem to me that the slower you need to disperse that energy (i.e. taking longer to get down the mountain) the slower the transfer of energy to the rim, hence allowing more time for dissipation (and the differences are pretty big. On ventoux an averag of 60 kph -which from strava seems ‘normal’- transfer time is 20 mins, at 40 kph it’s 40 min, at 20 kph it’s 1 hour). I would have thought that is more than enough time to dissipate the heat, but it would appear the convective effects are substantial (which on a thermodynamic basis I’m struggling to find a reason for as there’s no evaporative agent, so the heat dissipation should be straight line-ish). Thinking as I go, I guess maybe the tyre acts as a radiator….Just few points on this, to hopefully keep you from going down the rabbit-hole:
a) I doubt heat dissipation is straight line-ish. For one, even before evaporative effects, I doubt the airflow effect on heat transfer is insignificant (or linear). Also, consider heat dissipation in the pad vis-a-vis the rim. When you’re pressing the calipers together you’re cooling the pad with the hot rims and viceversa, instead of cool air. But, again, ¯_(ツ)_/¯
b) (edit: this has been said, but) While conservation of energy establishes that kinetic energy must equal potential energy loss, not all of the potential energy is lost the same way. So the air resistence on the rider does part of the work without giving off heat on the rims. When you’re going 80kph, even on a relatively steep descent you’re being almost completely airbraked. Mechanical equilibrium is reached through that, and not the heat producing friction on pads on rims.
c) Again, this is somewhat of an appeal to authority, but I think that the fact the Zipp engineers, whose thermodynamics knowledge surely far, far, far outweighs mine, chose to explain it on the basis of experimental data seemingly untethered to a theoretical framework might be a sign that they might be at least a bit unsure about it as well.
Love to know the engineering basis for the result 🙂I’m more of a desk engineer, but if you’re asking for a theoretical model, I’m afraid that just the thermodynamics are well beyond me. For starters you’ve got some kind of a convection-diffusion situation where the relationships between the variables are expressed in differential equations and nothing is easy to tease out. And then there are so many other things. Material-wise, you might also have something like a positive feedback where inter-surface adhesion between pad and track might also increase as a function of temperature, just to name another possible non-linear interaction to consider. Aerodynamics are never linear. Friction is linear but gravity causes acceleration, which then impacts the aerodynamics.
I’d venture a guess that gerally the faster you go the more the air both brakes you and cools your rims, but that might be up to a point where other things come into play if you pick up plenty of speed and then brake too hard. But ¯_(ツ)_/¯
So yeah, “Chariot of Fire”. It may seem like an appeal to authority, but for my money good old-fashioned experimentation is a very sound engineering basis.
Just a little FYI for all
Just a little FYI for all engineers in here (armchair, desk chair, and control chair):
“At Zipp we built a machine we called the ‘Chariot of Fire’ to try and understand all of this during our carbon clincher development, and it used a 400-lb. flywheel driven by an electric motor and could simulate most any type of downhill situation, different rider mass, and could even be programmed with real-world descending situations. It could also simulate environmental conditions like heat, cold, or rain. We found that the worst thing you can do during descending is prolonged, constant braking; the rim never has time to cool so the temperatures continue increasing at some pretty unbelievable rates. Even giving the wheel 2-3 seconds of rest during a test could drop temperature by almost 100 degrees F.”
There’s a bit more there. But my takeaway is that for those really big mountain days (ie. attempting to join the club des cinglés), alloy is a great choice, particularly if it gets hot. Have fun!
The Super is actually a bit
The Super is actually a bit more premium than the Pro. It actually looks a bit more like the Ultegra one than the 105, IMHO.
FSA probably a bit lighter, Shimano probably shifts better, but YMMV. I have an FSA crankset and it does the job.
I think fit is very important
I think fit is absolutely crucial but it is tied to function. If you want an easier commuter and better off-road bike I’d think about the 55 and maybe shortening the stem. If what you want is mainly a road bike, however, I’d go with the 53 and perhaps a longer stem with a bit of rise. You might eventually even end up lowering the bike a few spacers as you get used to the position.
Inseam is the least meaningful measurement. If anything I’d advocate the longer seat post for a little extra flex. Too little tube sticking out makes for a harsher ride, IMHO.
P.S. I’m 6’1″. I ride a 56cm road bike and a 19.5″ MTB.
Taking a bit of a different
Taking a bit of a different line, if you are skidding then wider tyres at lower pressure might help.
Mirroring previous comments, I went from (cheap) Tetkro’s to 105’s and it proved a very significant upgrade. I plan to go up to SwissStop / Koolstop pads once the stock ones wear out for a further boost. Ultegra/Dura-Ace seems to me to be more off a weight than a performance upgrade, though the newer 9100/8000 models are probably do offer up a bit of a generational improvement. Though at that point I’d rather set the money towards a disc bike. But generally, better braking is a definitely a good “pain saved for money spent” proposition, at least for my money.
I don’t mind the weather all
I don’t mind the weather all that much. It can even be enjoyable if the tarmac is dry and the cars aren’t spraying up all kinds of grime on your face. But it’s the thought of cleaning up afterwards that really spoils it for me.
For a climbing-oriented bike
For a climbing-oriented bike I’d look at brakes, gears, and weight. After fit, of course, which is the number one thing you’d want to look at in any bike. There’s really little else worth looking at when it comes to climbing, IMHO.
Assuming discs aren’t your thing, both of those bikes seem to hit all the right spots. But almost any of the above should do the trick. If you have a good LBS nearby I’d go with them, otherwise, unless fit is an issue, online is probably better value for the money.
Feels like a stranger drinking out of your pint.I know this isn’t, by far, the most unsound thing about your post. But, do you often share a pint with friends? Like out of the same glass, taking turns?
