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17h
comment What speed of wind gust will cause a cyclist to swerve by 1m or more?
Yesterday's Volta a Marina in Benidorm Spain had to be cancelled because of wind. You can see riders getting blown off their bikes here.
20h
comment What speed of wind gust will cause a cyclist to swerve by 1m or more?
There is not enough information given to answer this specific question, nor is there likely to be. The same cross wind will affect a large slab-sided lorry differently than a small car; the same cross wind will affect a thrown ping pong ball differently than a speeding bullet. From this you can see that it's not so much about the wind as about the characteristics of the object, and we would need much more information about the object (in this case, a cyclist) than simply the speed of the wind.
Feb
2
comment Riding into a headwind faster than my top speed - how is it possible?
@Frisbee The reference you're looking for is Equation (2) in this article. As for your link to that online calculator, I wrote them and they've corrected it.
Feb
2
comment Riding into a headwind faster than my top speed - how is it possible?
@ChrisH The reference you're looking for is Equation (2) in this document.
Jan
29
comment Riding into a headwind faster than my top speed - how is it possible?
Ah, I think I'm beginning to understand. Is your question, "if I can ride a maximum speed of X in calm wind, why can I still move forward when faced with a headwind of X?"
Jan
29
comment Riding into a headwind faster than my top speed - how is it possible?
The equation for bicycle drag is well understood though not always well known. In particular, the aerodynamic drag component of total drag includes airspeed as you're well aware -- but it also depends on air density. The reason why you can cycle into a strong headwind is because air isn't very dense. You would have a much harder time moving against a water current of 5 mph than an air current of 30 mph.
Jan
28
comment Why is a steady cadence so important? Or is it?
Have you read the answers to this question? bicycles.stackexchange.com/questions/12518/… In any event, if you examine what riders actually do, it is natural for cadence to vary. Riders rarely ride at a fixed cadence unless the conditions are also fixed (that is, same speed, same slope, same wind, same power).
Jan
14
comment Why does hunger have a much more drastic effect in cycling than in other endurance activities?
Your last sentence is unclear. It's not clear that less trained individuals can last longer before bonking while running than they do when cycling.
Jan
14
comment Why does hunger have a much more drastic effect in cycling than in other endurance activities?
@PeteH, a partial answer to how many calories a runner will burn per hour is given half-way down in this answer.
Jan
7
comment Does gear ratio affect Power?
@ChrisH One might think so, but empirically not. Many riders can produce > 1 kW for a few seconds in a narrow range of cadence but they might climb a nontrivial hill at, say, 200 - 250 watts. Empirical analysis of their cadence choices show that at a lower level of output they can and generally do produce fixed power over a wide range of cadence and crank torque.
Jan
7
comment Does gear ratio affect Power?
Welcome to bicycles.stackexchange. Your answer applies only instantaneously. For climbs of nontrivial duration, power is limited by metabolic processes (mostly, aerobic). That is, what you've written is true for maximal instantaneous power but when climbing any nontrivial hill your power output will be decidedly submaximal. There are still boundary values on gearing that will limit power production but and long as you are reasonably far from those boundaries your limitation is metabolic, not either force-limited nor limited by the speed of msucular contractions.
Dec
25
comment Should flywheels on stationary trainers be replaced periodically to avoid catastrophic failures caused by fatigue?
The flywheel replacement from Computrainer is free. Replacing the flywheel is definitely a more economical option.
Dec
4
comment Will this power2max power meter be compatible with Cannondale Synapse?
Was this for a BB30 version of the Type S? The difference between the BB30 and the BB30A is that the "A" has 5mm of extra width on the left side BB shell. Check for clearance there.
Dec
3
comment Will this power2max power meter be compatible with Cannondale Synapse?
I presume you asked Power2Max? What did they say?
Nov
8
comment Should I be able to peel off a glued tire patch?
Regular glue contains no "vulcanizing" components. Vulcanizing occurs under high pressure and temperature (normally, around 170 deg C., or about 350 deg F). Regular patches adhere well because the adhesive is better. If actual chemical vulcanization were occurring, the adhesive and patches used for latex tubes would be different from the adhesive and patches used for butyl tubes since latex and butyl are chemically different.
Nov
1
comment Is rubber cement in stationery stores the same as in tire patch kits?
If actual vulcanization had occurred, you would not be able to peel a patch off a tube.
Nov
1
comment Is rubber cement in stationery stores the same as in tire patch kits?
Not exactly. There often is real latex in rubber cement, and the solvent keeps it in suspension. The solvent volatilizes away leaving the adhesive and the rubber behind. You can use the same rubber cement whether your tube is butyl or latex; different formulations of rubber cement will include different amounts of rubber and different adhesives but no chemical vulcanization occurs.
Oct
31
comment Is rubber cement in stationery stores the same as in tire patch kits?
See my comment above to the other answer about vulcanization. "Rubber cement" is an adhesive that creates an airtight bond, so it's the cement that holds air in the (butyl) tube, not the patch. The patch is there to hold the cement in place around the hole and to protect the cement from abrasion. The molds used in manufacturing are sprayed with a "mold release" (think: Pam cooking spray) so you can peel the tube out of the mold. That's what you're trying to remove when you abrade the tube with sandpaper before applying glue and patch.
Oct
31
comment Is rubber cement in stationery stores the same as in tire patch kits?
Vulcanization does occur in natural rubber when exposed to sulfur and results in a cross-linked polymer but 1) most inner tubes are made of butyl, which is a synthetic rubber made from petroleum (which is why ExxonMobil is one of the major producers of butyl rubber) and isn't cured with sulfur and 2) vulcanization of natural rubber occurs under both pressure and heat. A typical vulcanization process using natural rubber and sulfur (with accelerants) is done at around 170 deg C. (~350 deg F).
Jul
31
comment How much speed can I buy
If money were no object, you could spend it on a streamlined vehicle like the Delft VeloX. It has CdA < .02 m^2 and special $400 tires (that are good for perhaps 20 km of use) with Crr < .002. On a flat road and zero wind, at 140 watts and a total mass of 105 kg you ought to be able to achieve ~ 80 km/h.