29

The OP linked 4 videos, the first 2 videos were long-course Ironman races, where time trial (TT) bikes were used, while the latter 2 videos were of short-course draft legal races where road bikes were used. In the latter two videos the competitors were either pros or elite amateurs. These individuals typically have multiple bikes and would be using a TT ...


20

It is pretty obvious. Just imagine the hill rose a bit, say to 5%. And even more, to 10%. Going across a mountain is never fast. Mountainous race stages are slow. The total meters needed to be climbed over the stage count, not just the different between the start and the finish. Do remember that the average speed is not averaged over the distance but over ...


19

The problem is that average speed depends on time, not distance. If you go the first 5km distance at 20km/h and the other 5km at 40km/h your total time is 22.5 minutes for an average speed of 26.67km/h (not 30km/h as you might have thought). Drag also increases with velocity squared, so all that precious potential energy you’ve gained by riding up the ...


12

It’s all about maximizing the positive effects of training while minimizing recovery time and injury risk You want to target different systems in the body as effectively as possible. A naive approach to training would be to (try to) train at race intensity and duration each and every day. However you’ll quickly reach a point where you can’t recover fast ...


11

The rear wheel is normal size (700), the front wheel is smaller (650). It was for aerodynamic reasons. By lowering the torso of the rider, the frontal surface of the rider became smaller. The configuration appeared first in triathlon and was later banned by the UCI in road and track events. Both wheels must now be of identical size i.e. 700.


8

Fast Fitness Tips recently addressed a similar question: whether an out-and-back time trial would be faster with still air, or into a headwind for half, tailwind for half, and how to pace the windy TT. Key quote: sadly the gain from the tailwind is not as large as the losses in the headwind and as a result there is a net loss in speed whenever its windy on ...


7

See rule 1.3.068 of the UCI regulations: "The national champion in the individual time trial is not authorised to wear the distinctive national champion’s jersey during team time trial events." I do not know when this particular rule was passed but it does not appear to have happened in 2019 so it must have been earlier.


7

Triathlon and time trial bikes are quite expensive and not wonderful to ride on open courses, hills, and in groups (in other words, general cycling). So, if you're not so serious about triathlons that you're willing to spend several thousand dollars on a bike that will see relatively little use, you'll likely be content with your existing road bike whose ...


7

This is absolutely specific on the heart rate zones of each individual. Each person has a different heart rate at their functional threshold (FTHR). Professional cyclists are able to cycle for a long time (most of the road race) almost at their functional threshold but the actual heart rate is completely individual. Even the percentage of the functional ...


6

I think what you are asking here is what's the better training routine: Ride 40 km at max effort (for that distance/time) - i.e. a 'time trail' every time Ride some shorter more intense rides mixed in with lower effort 'leisurely ' rides. The basic idea is that you can make better improvements by training at higher intensity for shorter periods, but you ...


5

Nominally no, an 11 speed speed crank will not work with an 8 speed drivetrain. As the number of speeds (number of cassette sprockets) increased as new groupsets were released, the sprockets were narrowed and moved closer together. The outside width of the chain was also progressively narrowed so that they worked with the narrower sprocket spacing. This ...


4

Generally it's true that hilly courses are slower. This is because the aerodynamic drag force is proportional to the square of the apparent wind, and a hilly course will have slow parts (uphill) and fast parts (downhill). The squared velocity term means the total energy required to complete the course in a given time increases when the speed is more variable....


4

Here's an empirical example. My local 10 mile course has a little bit of a climb (6-11% for 500m) at about half way, and then after doubling back comes down the same stretch of road. It's not a hilly course overall, but has a few other bumps as well. My average speed when I finish the descent is never as high as when I start the climb (whether or not you ...


4

It would be nice to understand what exactly happens when one rides at a leisurely pace, that eventually improves time trials. Do, for example, glycogen stores in muscle cells become gradually capable of storing more (glycogen), hence enabling a more intense workout during a time trial? In response to this part of the question, there is a well known table of ...


4

The following UCI memorandum shows the dates at which rule 1.3.068 was changed. I suspect this change was in the 2015 or 2017 revision, but I can't find them online. https://www.uci.org/docs/default-source/rules-and-regulations-right-column/2018/part-i-general-organisation-of-cycling-as-a-sport-amendments-to-regulations-as-from-22-10-2018.pdf


3

That's definitely tire rub. That frame has horizontal drop-outs to allow you to adjust the forward-back position of the wheel. When you take the wheel out, look in the dropout and you should see screws in there. I found a photo on the slowtwitch forum. Back them out a bit and then do another test fit. Make sure that the skewer is properly tightened too so ...


3

Looks like you have had significant tire rub on the frame for a while. I'm surprised you did not notice the friction and drag. If the abrasion is not all the way through the paint (the worst seems to be into the light colored primer) then you are probably OK in terms of physical damage. I might still be concerned about the possibility of heat damage, but if ...


3

If you ask shimano, they will say this won't work. But in my experience with 11spd cranks and 9 speed chain cogsets, it always works well enough. I've never had any significant problems using an 11spd crankset with 9 speed chain and 9 speed front derailleurs. The difference between 8/9/10/11 speed chain is the external width, not the internal size. The ...


2

Any meathead can race a TT - "Grog strong! Grog stomp hard on crank. Grog go fast." I don't even know why they bother doing it outside - they might as well do the sport on a trainer. Road racing takes strategy and forces riders to use their brains as well as their fitness and endurance.


2

Another lesser point is money - sport costs, and a triathlon is essentially three distinct sports in one. The bike is an expensive item, and so making use of what you have is a perfectly good solution. For some competitors, that will also be their commuter come Monday morning. I've even seen Mountain Bikes used in a triathlon, with road tyres and locked ...


2

In addition to Paul H's answer, there are several different triathlon distances from sprint to full iron man. In shorter races with hilly bike courses, or where there are many tight turns a regular road bike may be preferable.


1

TT Racing is all about watts and who can afford the best aeronautical engineers to squeeze out every piece of drag. Why have them on a road? Stick everyone on a WattBike and weigh the results with a coefficient that favours of the teams with the biggest budgets. Job done. :)


1

You could argue that any lightweight could race in a 'normal' race 'Please don't let the guy in front realise I haven't done a turn in an hour', but that would be unnecessarily imflamatory. The question should be rearranged to idendify the required outcome. If the question is: "Should TT riding be considered as a truer representation of a riders' speed ...


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