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Comment by niels_olson | Hacker News Reader

Am I the only cyclist here? I can't imagine voluntarily putting batteries in my bike on a long, mountainous stage. There's no way the batteries will last, and then I'm stuck with dead weight. And, looking through the actual documentary, I didn't see any incontrovertable thermal proof of a battery in any racer. In the guy posing for a shot, yes, but not in the cyclists laboring up the hill.

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Have you ever used an electric assist? a 50Wh battery weighs very little[1], the motors are similarly light, even by road-bike standards. Remember that there is a minimum weight, so you have a small amount of deadweight to play around with as well.

That would give a pro biker a 10%[2] increase in power usable over 1 hour of the stage. It would make the uphill parts way better while negligibly affecting flat terrain and downhill.

1: Maybe 300g for such a battery were it lithium polymer. Lithium primary cells can be even lighter.

2: Or 5% increase in power for 2h, &ct.

Ive some of these tube-size assists are 100 watts. That could be as much 30% in sustained riding. They were designed to provide half the power for commuters.

indeed; my point was that even a modest amount of power would clearly be a net-advantage versus no assist, despite the weight.

Although I strongly agree with you, and I strongly doubt this report, the story is that they change bikes during the stage. There's no limitation on changing bikes for mechanicals or any other reason. So the hypothesis is, they don't carry the dead weight. They change to the electric bike just for the Muur von Geerardsbergen or whatever.

I've got about 150 Watt Hours from a ~900g battery on my cheater bike. (link below)

I dunno how much ballast a really lightly built race bike has to carry these days, but even a quarter of that energy would likely make a dramatic difference - at 25W of assistance (which is something like 10% of a rider's total long-term output) a battery 1/4 the size/weight of mine would provide 90mins of assistance. Would that be "worth" 250 odd grams (plus motor and controller as well...)

http://www.hobbyking.com/hobbyking/store/__21384__ZIPPY_Comp...

Why do you need a cheater bike?

To clarify, my cheater bike" is a $50 eBay 2nd hand mountain bike that I use to commute to work - not something I ride dressed in lycra pretending to be faster than other people... I call it my "cheater bike", 'cause that what it _feels_ like riding it up hills... It makes me laugh everytime I ride it.

(I do _occasionally_ enjoy passing mamils on bikes that weigh less then their brekfast going uphill on my way to work.)

Every spandex rider you pass is pretending?

Nope - that was aimed at me not them - but I'm happy to let the stereotype burn stand ;-)

I will say to a first approximation, 100% of the RadioShack lycra liveried carbon fibre Trek riders I see riding through Sydney traffic on a weekday morning are _not_ Lance Armstrong class riders.

(Not any more than I'm a Carl Fogarty or Troy Bayliss class motorcycle racer when I put my racing leathers on and fire up my Ducati Monster...).

It's mostly posing and toys, with an unhealthy dose of brand snobbery and wealth signalling (and being brutally honest, I'm guilty of a little bit of both of those myself - no matter how much I protest that "My Ducati is just a fun toy! I;m not a brand conscious poser! Not like those _other_ Ducati riders...")

Well, even among serious hobbyist cyclists, very very few of them are or can be fit for world class pro cycling. Still, it's perfectly okay to use whatever clothes and bikes they enjoy, and it has nothing to do with pretending to be world class.

I imagine a nice lycra suit would actually be comfortable. I don't know, I go with jeans and a T-shirt (when the weather is warm enough for that) but proper cycling wear should help with chafing down there as well as stopping your clothes from dripping sweat while still keeping you warm enough for when you're starting to get exhausted or the weather gets chilly. These problems exist even for non-sporty people cycling to work as long as they ride fast enough for their bodies and have a long enough commute...

Toys? I guess. I would say all hobby equipment is toys.

A little off topic, but what's cycling like there?

From what I've heard (never been there) Australia is about as close as it gets to the perfect society... except they hate cyclists like the plague?

> Australia ... the perfect society

Hahaha

I commute to work on an e-bike in Melbourne. My route is mostly on trails and roads with dedicated bike lanes, so its pretty easy going. The hate towards cyclists might be a bit overstated. Some of it is justified as cyclists will often break road rules, I usually see multiple cyclists run red lights every day. Ive seen more aggression coming from cyclists then I have seen from drivers aimed at cyclists, but obviously aggressive drivers are much more dangerous than aggressive cyclists.

What a weird implication that you need to be the best to use good gear.

The pro-style clothing isn't posing or brand snobbery. Jeans are way too hot, cotton clothes get uncomfortably sticky from sweat way too fast and let cold wind go through them. Proper bike clothes allow me to feel comfortable for a long time and won't get me sick.

As for a good bike, it's just a better experience. I've owned a bunch of different bikes, starting with a old soviet fixed-gear Školnik, and ending with my current Trek road bike with fancy gear. Everything about riding the Trek is better than any of my older bikes. The gears change in a smoother fashion, I can roll on without cycling for much longer, and the effort-to-speed ratio is much better, allowing me to reach way higher speeds than ever before.

Sure, but I see guys riding to work in "pro style clothing" with Rabobank and RadioShack logos all over them. My cynicism makes it hard for me to come up with justifications for that which are not super easy to make fun of...

I get the "owning nice toys" thing - I even get the guys who are 20kg overweight spending $5k+ to get a bike that's 2kg lighter than a bike that costs 20% of that. To me though, it starts seeming weird when they do that while dressed up in sponsor logos for companies that sometimes don't even exist in this country...

(And it's not just lycra wearing mamils either, I don't get the motorcycle riders who paint Repsol livery on their Honda or Aruba or Xerox logos on their Ducati...)

Ah, you're talking about sponsor logos. I didn't get that at first. The only thing I know about RadioShack is that it's a store chain. I assumed they sell some rebranded bike clothes. Having sponsor logos on you that weren't put there by the clothing store seems indeed a bit quirky. I haven't seen that myself.

Does your cynicism carry over into teamwear for all sports? Baseball hats? Logowear in general? None of these people are pretending they are linebackers and point guards.

One thing you may not know is that logowear is like 90% of available men's cycling gear. There's an element of market failure.

Yeah, it does - and hypocritically so. I'm currently wearing a tshirt with a Kees Van Der Westen Speedster logo on it (an espresso machine I covet badly, but am not prepared to spend $10k+ to own). I own and wear various motorcycle branded tshirts and coffee brand tshirts, as well as many many band and musician merch tshirts. So I;m just as guilty of "making a staement" with what I choose to wear. But, of course, _my_ choices are all rational and understandable. Those _other_ guys who dress up like Lance Armstrong while riding to work are _clearly_ worthy of my derision, right? ;-)

Doesn't that kind of defeat the purpose? Why not ride a scooter?

Not aimed at you personally, but in my commute I'm not happy with all these motorized bicycles on the bike lane nowadays. They're usually ridden by people who don't race seriously, and are now riding 30+ km/h, but doing it as though they're still going 15 km/h: not looking behind them before passing or turning, immediately ringing their bell if you're in front of them, without first looking if maybe there's a reason why you're slowing down, not keeping distance. One slammed into me when I stopped to yield for traffic. Yield? Why would one yield?

Surely the purpose is to get to work. The motor certainly doesn't defeat that.

I also ride motorcycles, but the bicycle I can ride int the lobby and take up the lift to the office - it's quicker door-to-door (over 8km) than the motorcycle, which I sometimes get to park close by but if I don't come in early I end up parking a few blocks away (or _gasp_ paying for parking).

I;m with you on the dangers of people who don't have good situational awareness zooming around on electric bikes - but I think I'm pretty good there, you don't survive 25 years as a motorcyclist doing 15-20k miles a year without being pretty good at knowing what's going on around you and riding accordingly...

Another point, I know a lot of commuter bicycle riders, and some of _them_ think the skinny-wheeled-carbon-frame crowd doing 30+kmh in bike lanes should GTFO as well... (And I've got motorcycle friends who reckon the lycra-crowd should stay off the country backroads doing 50kmh when they want to zoom past at twice the speed limit... People, huh?)

(Also, my cheater bike is _way_ cheaper than a scooter, it's a $50 eBay mountain bike with ~$130 worth of Chinese hubmotor/controller/stuff, and a $70 battery. And crucially, I can ride the cheater bike home from the pub after a few beers... )

It's not so much a comment on their situational awareness, it's that they're riding one vehicle with the style of another. It's behavior that would probably be harmless if they were going half the speed.

If you drive a car as though it is a motorcycle, you're also disrupting traffic and creating danger.

Your cheater-bike-build sounds pretty interesting. Did you describe the build-process in detail somewhere? Or would you care to write it up?

It was a pretty complex and sophisticated process.

First you need to get borderline drunk and start browsing AliExpress late one night, then forget all about it by morning. A few months later a bike wheel with a hub motor and controller unexpectedly show up by courier at work. This reminds you why you bought that lipo battery months back thats way too big for any of your quadcopters. Then you spend an hour or two the next Saturday afternoon bolting the wheel and ziptieing the wiring and controller onto the $50 eBay mountain bike you bought a few years back when you decided it was "time to get fit" - which had been sitting in the garage ever since after having been ridden only once or twice. You then notice the battery is an _almost_perfect fit into the drink holder, and you can make it into a perfect fit but putting the battery into a stubby holder! Win! A bit of work with the soldering iron having robbed connectors and heatshrink from the quadcopter parts bin, and it's ready to go. You then hop onto the bike and cruise up all the nearby hills grinning like a loon and laughing out loud.

Im pretty sure that covers all the important steps. If you need me to check my notes about exactly what you should be drinking to get the right sort of AliExpress ordering buzz going, let me know - it was _probably_ bourbon ;-)

> And crucially, I can ride the cheater bike home from the pub after a few beers...

Not in the UK, you can't. Drunk in charge of a vehicle, no matter that the vehicle is just a bicycle.

In Germany the same.

If you are caught drunk (over the legal limit) on a bicycle, they will remove your _car_ driving license ( if you have one) and you either the let the bike there and call a cab or you have to walk with the bike home. Of course, next day you need to pay them a visit to pick the driving license :).

Yeah - technically it's true here as well. Practically, short of mowing down a pedestrian in front of a cop (or some other spectacularly provocative bad behaviour), the odds of getting breath tested while riding a bicycle are close enough to zero to make no difference. (Having said that, I once worked with a guy who lost his driving license after getting caught while riding a horse home from the pub - he was the kind of angry mouthy guy who was gonna end up like that somehow anyway, I suspect he worked quite vigorously at getting the cop worked up and angry enough to bother doing it...)

A scooter's harder to park. And depending on how long your commute is, half-cycling might be the right amount of workout/time where cycling the whole way would be too much. (I sometimes take the train halfway to work and cycle the rest of the way or vice versa).

Modern race bikes are already deadweighted to make it to the minimum weight, so it's not a question of making the bike heavier.

Not deadweighted in the amounts a battery with enough energy has to weigh.

But it's conceivable they've found ways to shave the bikes weight down even lower to accommodate the battery and motor.

The maths doesn't work like that. Weight is actually not a huge factor in cycling performance because you mostly go horizontally. Top athletes only go for super-light bikes because they need every tiny advantage they can get.

Adding a battery will increase the weight a bit, but the extra power from the battery more than makes up for it. Let's do some massively oversimplified maths:

A lithium ion battery might have an energy density of 0.5 MJ/kg. A typical insane Tour de France climb might be 2000m. To lift itself that high, the battery-motor system needs to only be (20009.81/500000) ~= 4% efficient!

The actual efficiency will be a lot* higher than that. Usually over 50%, so adding a battery is definitely worth it.

(I haven't mentioned the weight of the motor, which is usually more than the battery - at least on conventional e-bikes, but it still works out as being definitely worth adding.)

With the minimum weight requirements in bikes they are having to add weight inside the frame to meet the minimum. Adding a battery + motor that provides even 20W of assist is a huge gain for a bike that still only hits the minimum weight.

The key thing is being able to respond to attacks and keep a gap from forming. Often all this takes is a well-timed burst of power for a few seconds at a time. Easier said than done, but juice from a battery could easily make the difference.

IMR 18650s are very light, will fit in pretty any much tube on a bike, potentially even inside a tyre on a tubeless job, and will push 80A for 120 seconds, which is a crap-tonne of power.

Having a battery assist is the difference between working hard for an entire hill climb, or being able to do 30 seconds on 30 seconds off and fartlek your way up the hill - which is the difference between winning and losing.

For the mass of 10 cells (500g) you can get 25aH - which works out as about 60W for an hour at 2.5v - which is enough to save you 10% of your energy expenditure over a one hour race if you're going hell for leather - which is still the difference between winning and losing.

They can easily switch bikes pretending that they have a flat tire, or any other issue. IIRC suspects of using batteries have also been seen to switch bikes at suspicious moments.

The thing to understand is that often times the bikes that pros ride are below the minimum weight as set by the race. They'd be carrying dead weight either way.

It will obviously pay for itself in terms of energy... in the limiting case, you could just hop in a Tesla and win the race.

Hm. I love the idea of a logic proof, but is this correct? In the limit the Tesla runs out of battery and you can't push it up the hills.

Interestingly, they race electric motorcycles at the Isle of Mann TT, and the riders all talk about how it's a different game to racing fuel-powered bikes - the bikes are capable of using up all their energy much more quickly that a fuel powered bike, so it becomes as much an efficiency trial as a race, they need to manage their energy consumption to ensure they make it to the finish line (all while still averaging over 100mph around the 40-odd mile mountain racecourse...)

I work on a team that designed two electric motorcycles for the IOM TT Zero. Yes, it's a very different game from the gas races. Aero and energy storage on board are the primary concerns - the top team for the past several years has been successful primarily by packing on ~20-30% more energy than their competitors, so that they can go faster, for longer.

The TT is really an edge case, though, since it is such a long (38mi) and high speed course.

If you've been there a while, I probably met you, or at least your colleagues - a few years back at Maker Faire (where you were showing off a yellow motorcycle, from memory R6 based?), and again at Sears Point for the first US TTxGp back in maybe 2010?

One of your guys (Richard?) offered to get me good prices on Agni motors and packs of A123 cells for $300-ish per kWHr. (I should have taken him up on that... My current ride is a probably-illegal-in-CA 125cc two stroke Cagiva Mito - which is a barrel of fun! I could easily see myself looking for 30 or 40kW of electric motor/controller/battery to jam inside it next time it needs a complete engine rebuild...)

Hmm, not us! We were there in '13 and '14, and our bike was built on a CBR1000RR chassis. I can't remember who had a yellow bike, although it sounds familiar... it may have been a bit before my time if they were talking about Agni motors.

Small world :)

I meant the limit as battery / bike -> infinity for a fixed race length, not the limit as distance goes to infinity. In the latter case, the human dies as surely as the car. The race stages are only about 200k, which is no problem for the car, especially at the relatively low speeds of the bikes.

The dude who was cruising up the hill without standing on his pedals seemed pretty obviously using an assist.

Standing on pedals is actually less efficient than remaining on the saddle. You break out of the optimum cadence.

However it does shift the work to different muscles which is why some riders stand for particular stretches of hill prior to a seated sprint.

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