Payday Loans Online Payday Loans Online

Archive for the “Techology” Category

Polar CS600The new Polar CS600 cycling computer is the latest toy to grace the handlebars of all the best dressed pro tour racers these days. It is a comprehensive data recording device to show every conceivable detail of your current and historical cycling performance. It’s light weight, small, ergonomically perfect and carbon fiber matched to your top-end handlebars or stem. It is also at the core of a system that covers the spectrum from speed/time/distance data to power, heart rate and cadence and then connects all of that into a nicely integrated computer software package that can keep the technophile entertained and enthralled for days on end. Email your performance data to your coach and get set to win that next big race. Or gazump that next baby photo show and tell by reaching for your fantastically detailed heroic ride trophy graphs.


I have had two Polar S725X cycling computers over the past two years. The S725X was Polar’s top-end computer, with the flexibility of attaching either to your wrist or to your bars. The basic S725X would record all the usual ride information (speed and distance functions), plus heart rate and, with the addition of special sensors, cadence and power. You also get altitude, temperature, ascent, decent and, of course, time of day. There were a few problems with the S725X, though. For starters, the speed and cadence sensors were big, and not a particularly easy fit to modern curvy carbon (as is to be found, in abundance, on my new Pinarello Prince). Worse still, the device has only a year’s worth of battery life; after which you have to send the whole show back to the distributor for a new battery cell (a very strange and rare button type battery that only Polar seems able to source). This battery deal was, in fact, the reason why I ended up with two S725X’s in two years. I tried to replace the battery on my first unit myself…But the worst feature of all was the frequently feeble capacity of the unit to reliably read heart rate information from the included chest belt. The problem here is to do with the S725X’s analogue wireless system. In a good headwind, the data is simply not readable and the unit helpfully suggests that you are either dead or hammering along at a pulse of 250 plus! The cadence sensor’s range was so poor that it needs to be mounted as close to the computer as possible; which for my bike precluded a sensible chainstay mount. Instead, I had to install the big ugly cadence sensor on my downtube (in reach of a crank arm mounted magnet).All of which recommended strong interest on my part in Polar’s announcement (in June) of the CS600. The clincher was its appearance on the bars of Valverde’s brand new Pinarello Prince in this year’s Tour. If it’s good enough for him…


The CS600 addresses and essentially fixes every single issue I had with the S725X predecessor (which is still on Polar’s production list, presumably for riders who still like the idea of a cycling computer that can also be worn on your wrist as an oversize watch replacement). The CS600 comes with totally redesigned sensors, which are much smaller than before (but have no replaceable batteries; thus requiring their replacement, apparently, every two years at the cost of AUD$90 a go). Better, the whole system is now digital. Digital signals are vastly more robust than the feeble efforts at communication that always dogged the S725X. Now you can place the cadence sensor way back on the chain stays. The speed sensor can be casually placed wherever you like on your forks. And heart rate readings hang in even through a gale force headwind.The CS600 battery is now user replaceable, and is apparently good for two years.

One feature I really love is the built in inclinometer. Now I can get an instant readout on the slope of any hill, in degrees or %. Just what you need to find a local Motorillo or Alpe d’Huez. Plus, if you dig around in the files after downloading to your computer, you can read off the total ascents and descents for any ride, in metres or feet. You can even work out the total distance you spent coasting as opposed to pedaling on any ride (provided you have the cadence sensor installed).

I have not yet tried out the power recording side of the story. This works through the installation of a power ‘sensor’ that installs on the upper pully wheel of your rear derailleur; using pressure on your chain as a proxy for power applied through the cranks. Apparently, the accuracy of this setup is a bit mixed (a stunningly comprehensive coverage of a number of power monitoring devices, including the CS600, was presented over issues 35, 36 and 37 of Australia’s Ride magazine – one of the best cycling magazines on the planet).

The CS600 was launched with a new version of Polar’s cycling performance analysis software, ProTrainer 5. This is a vast improvement over the old, aging and clunky Polar Precision Performance software that came with the S725X. But! I do most strongly protest…Polar continues to ignore the Macintosh here. Why oh why can’t they port this software to the Mac? I have to rely on Parallels to play. Not happy! Plus, why oh why does Polar persist with infrared for its connection to the PC? Infrared connection is now a thing of the past. No one uses infrared in these days of bluetooth, wireless or usb connectivity. But I suppose infrared is one step up from Polar’s equally strange dedication to sonic computer connectivity that is still to be found on some of their running monitors. The latter has to be experienced to be believed…(imagine a captive cricket sqealing in distress when held close to your computer’s microphone input and you will start to get the idea…). I am not, however, saying that this new software is perfect (ignoring its Mac incompatabiity issues for the moment). It is still a bit clunky. But then again, if you are familiar with the astountingly feeble attempts at coding attempted by the likes of CycleOps to connect their powermetres to the PC just about anything else looks good in comparison. It seems that cycling performance software is operating on a decade lag to the rest of the computing world.

Users of the S725X will also be pleased about the rearrangement of the menu systems on the CS600. Now you can quickly access a stream of different screens while you ride. You can opt for a screenfull of altitude related readouts (inclinometer included), speed related information, heart rate centric data, lap time data and a strange looking graphical read out screen that I have not yet fathomed. Or any combination of the above that you might choose to customise on this most astoundingly customisable of cycling computers. It will even tell you the time and date.

But it works. Both the software and the CS600 itself.

Finally, I have left the worst bit to last. The price is kind of interesting, bracing or distressing depending on the way you see things. The unit itself costs AUD$700 (including one speed sensor). Add to that a cadence sensor at $90 and a power set up at $600 more and all this starts to add up to the price of a good entry-level racing bike. And then if you want to spread the CS600 over your stable of bikes (which I have done), you have to pay out $90 for each additional sensor (you can store details for 3 different bikes on the unit).

So, there you have it. One nice and nearly perfect cycling computer that can record anything and everything you could ever want to know about your performance and your rides (the only thing missing is GPS). All recorded with impressive accuracy, fine detail and robust efficiency.

Cross posted to

Comments 4 Comments »

The best part about work these days is the trip there and back again; on my wonderous new Pinarello Prince carbon. So much so that I am even tempted to do the trip in a howling gale. Like today. The outward journey into the wind is a struggle, but you get used to it after a while. It’s the return trip sailing before the gale that sounds the most fun. Cyclesurfing.

With the wind from behind but slightly to the side, I just know things can get exciting when passing through gaps in the trees. But with a new bike spoiling for speed, all is forgotten as I tuck down into my first long descent. It’s a seven percent decline (courtesy of the readout on my new Polar CS600), nice and fast. Soon I am up to 60km/hour and having a ball. Until the first gap in the trees. The wind hit like a pothole.

riding alongThen the steering went. Like a front wheel puncture matched to a suddenly broken rim. I know what this is; it has happened to me once before. Death Wobble! Knowing my physics I know it’s all about me amplifying a new vibration dynamic in the steering through clinging like death to the bars. So I free my grip, force my arms to relax. Unlike last time, this did not work. The wobble is getting worse. I am braking with caution but even as the speed declines, slightly, the wobble continues.

That’s all bad enough, but the real issue is the huge double semi trailer truck on my tail. It’s about two bike lengths back and impatient to overtake. Now my thoughts are focusing pretty clearly on my inevitable crash accompanied by a quite painful bird’s eye view of the underside of 100 metres of truck. Death is pretty well assumed by now. I can’t brake any more as the truck will run over the top of me. I can’t control the wobble so I will probably crash out any second. Think.

Then I vaguely recall some advice from a discussion forum someplace: you have to break the amplification of my wildly wobbling forks. Pedal! Push the cranks. I pedal. I power into my cranks, I sprint like Pettachi… It works! Like a spool taking up the slack, this pedaling is winding out the wobble. Back in control. The hill levels out and now I am on the flat. The truck overtakes and my heart rate recovers down to 170bpm (courtesy of my ever so clinical and unflinchingly uncaring Polar computer…). That was fun, wasn’t it! So now I have discovered a downside to this superlight, superstiff carbon masterpiece of mine. I start to wonder about all those Caisse d’Epagne Prince riders running the Alpine downhill hairpins in this year’s Tour de France. Give me an uphill ride or a mountain bike anyday. Think I will walk down the hills from now on…

Comments No Comments »

A full review of my new Pinarello Prince Carbon (2008 model) has been posted to Here is a direct link.

Here is a summary of the full review

my new Pinarello Prince CarbonThe official Pinarello website suggests that with the release of its new Pinarello Prince carbon, its previous high end offering, the Paris FP Carbon, is now ‘unavoidably in its shadow.’ That’s a bit harsh and I was keen to test this assertion as I now have both the Paris and the Prince (a totally extravagant but wonderful overindulgence in Pinarellos, I know).

After two weeks, I now have around 500km of connection with the new Prince; in the hills, on the flats, rough roads and not so rough. With some good intervening rides on my Paris to keep my ride impressions grounded or benchmarked against what I had long thought was the best bike I had ever ridden.

The Prince is dedicated only to one thing: going fast. This is a racing bike. It has no other purpose.

With that in mind, it is quite severe on the road. It gives a fairly harsh ride, at least compared with my Paris but not as harsh as the Time VXR I tested a few months ago. It is a harshness that is actually desirable. It is a harshness that never overwhelms or reduces the desire to ride for three hours or more. It is not a harshness to cause discomfort or the desire to retire.

The most obvious feature of this bike, that literally hits you first, is the stiffness of this frame. Everything you have in your legs gets to the road. This bike is a statement of efficiency. My first reaction is that the 300 grams of lower bike weight plus its total lack of frame flex is the equivalent of one gear, everywhere you go. It feels like I am in a lower gear. So, naturally, I drop down to a smaller rear cog and go even faster. That’s the whole point of this new design.

Descents are even more precise than before. And the Paris was renowned as a brilliant descender. The Prince is even better. The precision with which you can fly down hills is inspiring and miraculous. You always feel totally in control. Hill ascents are even more revelatory. The Prince is born for the hills. Perhaps the Fulcrum Racing Light’s fitted to my Prince are to blame to some degree, but these days, I look forward to the hills more than ever before. This thing presents a veritable soundtrack for climbing.

But does it put the Pinarello Paris in the shade as Pinarello’s own web site suggests? I would say most emphatically not. The Prince is the Yin to the Paris’s Yang. The two intermesh as a perfect pair. They are compliments not strict competitors. If I were heading off to Europe on an extended tour of the French classic climbs, I would take my Paris. If I were racing there, I would take the Prince. These are two bikes with quite different personalities. One is unremitting perfection to the art of the race, to be relished when in need of speed and the other is there to be a more compliant companion to more multi-purpose rides.

Comments 9 Comments »

I would imagine that I am not unusual in thinking that the prospect of a ride under heavily overcast sky, intermittent snow, a temperature of 3 degrees C and howling gale force wind is somewhat challenging…Though I will confess to actually heading out for a 33km run on my XC bike yesterday just to see what a hurricane wind would actually be like on a bike. It was great fun! On the downwind leg. But guess what? The return leg was all into a 100km/hr gale. Not fun. Especially when the wind chill factor managed to freeze the water in my water bottle so I had to go thirsty as well. But it was fun being lifted off the road and shifted sideways when I hit a wind gust in one valley channel.

But all this is still better than the horrendous thought of hitching my bike to that indoor trainer contraption in the shed. The experience of spinning along for an hour, going absolutely nowhere and sweating buckets while staring at a never changing iron wall; is kind of not fun at all. Not good for the bike either. I must declare a pathological hatred for these rear wheel clamping torture machines. I am not that desperate.

Which is not to say that heading on out into wind, black sky and bracing cold is such a huge improvement. I will confess. When it is actually raining, the torture machine wins, just.

There has to be a better option; a lateral parallel universe where I can go when this world is so cruel to us obsessed and addicted cyclists.


And there is! There really is! It’s called CycleOps. I stumbled on this one when visiting the big city cycling store a few months back. Literally. I bashed into it when looking for some other stuff in the road cycling section of a certain Sydney based emporium (OK, Clarence Street Cyclery). It did not fall over. It was like hitting a wall. This thing is HEAVY! SOLID! and way way out there! It’s the CycleOps Indoor Cycle. I had seen this one in a clip attached to last year’s Tour de France where they showed the much challenged (but I really do think totally innocent) Floyd Landis warming up before a stage. He was on the CycleOps. Checking out it’s integrated PowerTap power readings. Cool! I wanted one then and wanted one even more when I smashed into it on the road bike floor of our big city cycling megastore.

But it was a three month wait. Too heavy to send by plane. It had to come in by ship. But now it is here.

It is as different from my old indoor trainer as is George Bush, John Howard or any economic rationalist you could name from an intelligent man. Quite a lot!

In four days I have clocked up 250km. I have raised my average cadence to over 100 and I am pleased to report a workout that ties a heart rate of 165bpm to a power of 280 watts to a speed of 40km/hour. I never imagined I could pull that one off (Floyd can sustain 280 watts for 30 minutes; somewhat more than the three minutes I like to maintain). All the time while being blasted by really really loud progressive metal music (latest joy is Pain of Salvation). And it is really really cool to be really really hot and sweating while the snow is coming on down outside the window. Sign me up. I am addicted

Comments No Comments »


A colleague made a comment the other day that was a bit like a Zen Koan (deeply mysterious statement that makes you think and then inspires a creative newthink on your old deeply established ways of seeing things). I am not sure he intended his comment as a koan. Perhaps he did. If so, I was a bit slow on the uptake as this only occurred to me a day later.

The context for the statement are my diatribes on the world shaking need for every single human being to take up cycling and all their excuses for not doing so being so much rubbish… You know, that kind of hyperbolic cycling proactive hysteria making that kind of dominates my blog…

Here’s what he said: ‘you know, I could never ride a bike because I could not wear all that gear’. He went on to suggest that he might look a little odd, he thought. Or something along those lines.

A short and, as I said, very koan-like statement!

Then I happened across an article in the latest edition of Bicycling Magazine about Shimano’s new agenda to sell bicycling (the whole package, both bicycles and the cycling experience) to all those people who would not be cyclists. The other 90% of the population, in other words. In American terms (Bicycling is a US publication with a determination to largely ignore the rest of the world), this plan is not about selling to those 6 to 7 million US citizens who can be regarded as cycling enthusiasts, or even to those 14 million who might be classified as ‘casual cyclists’. No, it’s about selling the whole cycling package to those 160million people who would have no intention of entering into our cherished domain.

Shimano contracted some innovative market research to try to understand how these NON-cyclists perceive cycling, the bicycle buying experience, what they would be prepared to pay to buy a bike (about $300 or so) and what they reckon about the experience of entering a conventional bicycle shop. And so on. The aim of all this is to create a ‘$1000 tech-laden bike that would lure baby boomers and their loose change off the couch’ (Bicycling, April 07, p. 134).

The result is a new paradigm of cycling called ‘coasting’. I think it is brilliant. This is not just a new piece of technology; it’s a new approach to cycling much like the jump we made from road cycling into mountain biking. Coasting could become the third leap after mountain bikes to update cycling into the next generation. Basically, it’s a new type of bicycle, a new way of thinking about cycling, a new way of becoming a cyclist and a new process of cycling. All of which would package into a beautiful response to my colleague’s koan-like statement.

Here are some specifics. The new coaster bikes have no levers of any kind on the handlebars. Breaking and gear shifting happens via automatic hubs (clever technical innovation that all happens behind the scenes, via technology built into the wheel hubs). Different makers will be producing coaster bikes (Giant, Raleigh and Trek for starters). The pictures I have seen indicate a highly laid back, cushy seat, pedals forward, upright ‘townie’ kind of a bike. There is no hint of speed-orientated, hard pushing, sweat inducing competitive athleticism here. It’s more a kind of all-smiles, bike path meandering, rolling-along, European urban commuter, coffee shop-like experience that should look a bit like cycling in Holland and the old Chinese school. But updated for the next generation. Here, you ride in jeans, about-town shoes, and whatever else you would wear down the mall.

Now why would this appeal to a Pinarello polishing zealot like me? It’s simple. If we can get even a minority of the non-cycling public into this new paradigm of cycling, there are less cars on the road! We get a vastly enhanced level of tolerance for cycling and cyclists. We get marked reductions in green house gassing. We get fitter people everywhere. We get happier people everywhere. And we cycling nutters get enhanced cycling-sensible road maintenance, improved recognition as fellow members of the human race (somewhat lacking when cars pass us by) and a profit boost for our cycling suppliers so that they can keep us obsessives in the manner to which we have become accustomed. A real win win outcome.

Comments No Comments »


I was watching the cult English motoring programme, Top Gear, (yes, I know…) because it was all about that astonishing re-creation by Volkswagen of the Bugatti, the Veyron (which is a technical exercise car that would cost you AUD$25million if you could get one). Jeremy Clarkson (the host of Top Gear) was racing his mates on a plane from Italy to London (he won).

This is, he said, the ‘greatest car ever built’. It is one of those single purpose, obviously cost is no consideration, engineering exercises to create the most singular, perfect motoring experience of all time. It’s not about building a mum dad and the kids wagon at some price point. It’s not even an exercise to update motoring tradition like Ferrari et al via a family linked, registrable iteration on an ongoing theme. It is just about building the best possible car on the planet. While the result is obviously a pure attractor for the motorhead, it’s appeals are as amenable to the professional racing driver as well as to the drooling adolescent approaching his provisional driving license. This is, in other words, the ultimate statement of motoring perfection.

Now once upon a time, I would print out the picture above and put it on the wall. I’d be grabbing pics for my computer screensaver. I’d be a cult fan. You betcha.

But, segue to this…

Another ultimate statement. The Pinarello Paris carbon. Now here we have another vehicle designed for no other purpose than ultimate perfection in its intended racing without compromise class. This is a full professional money-is-no-object, designed-to-win vehicle for those who make a living from being the best. This is the vehicle Valverde rides. Like the Bugatti, it has an illustrious racing pedigree (remember Indurain?). Like the Bugatti, it is named after the engineering fanatic that created it. Like the Buggati, it is from the vehicle obsessed Italian domain of embedding the culture of racing passion into a statement of engineering perfection meshed with design and pure lust. But unlike the Bugatti, the Pinarello Paris is the purest statement of engineering-racing-tradition drenched perfection. There’s no attempt at meeting burearucratic nurd design rules for politically correct safety considerations and compliance with idiot proofing down to the lowest common denominator of those who would challenge the rules of Natural Selection. There’s no CD players and air conditioning. No concessions to those who would use their vehicle as a surrogate for youth. Nope, no cushy leather and bucket seats here. This is a vehicle of the racetrack. A vehicle straight from the Tour de France, without modification. The real deal. And road legal. And, a more efficient statement of engineering perfection (the petrol engine can never be even vaguely as efficient as a bicycle; any bicycle).


So, if you are wanting the ultimate statement of Italian passion-derived, vehicular perfection, the choice is no contest. Pinarello Paris (or, if you follow Pinarello’s own advice, the magnesium Dogma which is even more expensive). All for the price of a set of tyres for the Bugatti. Or less.

So, gimme the Bugatti. I’ll then sell it and keep myself in Pinarellos for the next 100 years, one per month…

The really scary thing about my diatribe here is that I actually really do mean it! I am not suffering from any kind of envy delusion. I’d REALLY rather the PInarello (so long as I could not cash in the Bugatti and translate that into a Bicycling cash flow extravaganza for the next 100 years, as I said).

Comments No Comments »


For me, listening to the wind in your ears is great, sometimes. Mostly when out on my mountain bikes (where I need to keep an ear on where my dogs are at and untoward mechanical noises like rocks crunching derailleurs). But on my road bike, music and cycling are made for each other. These things are inseparable and reinforce each other towards some kind of a synergy of experience not on offer from either cycling or music alone. Naturally, adding music to the cycling equation is not something you would do if you ride with others a lot…But most of my riding is solo and on remote rural roads.

Like most things, there are some interesting myths out there about things like riding with music in your ears. The most important is that riding with music blocks out all those important audio signals like the sound of cars about to hit you and keeping tabs on scrapes and hissing sounds indicating imminent breakdown. So, like a good amateur scientist, I tried it both ways to see what’s what. Basically, there is no difference. Wind noise from traveling at anything like a normal speed (20km/hr, say), will basically cut as much in the way of environmental sound perception as sticking a good pair of noise excluding earphones in your head. In one of my ‘trials’, I was riding along a totally deserted dirt road (with no music or earphones) only to notice, with some rather stunned surprise, a massive cattle road train (long long big truck) in the process of overtaking me. Now how on earth could I not miss hearing that coming? Am I deaf? No, actually, I have highly sensitive hearing. Honestly! The problem was I was riding into a headwind and the wind-noise managed to completely disguise this rather noisy truck until the last second. So much for forgoing music to stay tuned to the road.

For me, an interesting discovery about cycling to music is that what I like to listen to on my bike is probably not what I would usually listen to when not. My usual musical taste is classical, jazz and other highly dynamic stuff (big shifts between loud and quiet bits). My exclusive choice for cycling is music with a solid rhythm, long long improvisationary build ups and thundering crescendos (hopefully to coincide with the conquering of a hill). For me, progressive metal fits the bill to perfection and the icons on my list are Porcupine Tree and Dream Theater. Tool, Opeth, The Mars Volta and Nine Inch Nails fill out the space to keep me going for the 500 plus hours a year I spend in the saddle (552 hours for 2006; spread out over 13,379km to be exact).

Which brings me to the one area that I have experimented with more than just about any other aspect of cycling. What choice of hardware? The music machine must be an iPod. To have anything like the storage to cover a nice 5 hour ride with variety and sound quality, it has to be a Nano (8GB). When you spend silly amounts on feather weight bikes, it does not make sense to cart a heavy music player around, does it! The iPod Nano is utterly perfect. It is also pretty resistant to mist level showers and sweat.

But much more important is what you put in your ears. Over the years I have tried everything. Standard Apple earbuds are useless. Can’t hear anything over the wind noise and the music fidelity is a bit like listening to a concert over someone’s mobile phone… Then there were a string of cheapish ‘noise isolating earbuds’. These are becoming increasingly common. They are earbuds with a soft rubber or plastic bulb on the end that fits into your ear and, through a tight fit, exclude outside noise, to a degree. While the sound isolation is often OK with these things, all they do for me is amplify their totally unlistenable audio quality. All bass, no treble and the whole thing mixed into audio mud. I recall literally throwing a pair of $70 ear buds of this kind into the weeds beside the road after ten minutes of listening…(V.Moda brand). Yuk. Junk.

Next up was a pair of Shure E5c’s. Now those of you who know about these will be wondering about my sanity, by now… Let us just say that these are at the extreme other end of earphones (they cost AUD$1000). Lovely! Great noise exclusion, terrific sound from their twin drivers (one for low and another for high frequencies). Until I broke the cable; now they are dead and I was rather distraught you might say. Then I tried a pair of Ultimate Ears superfi 5 pro’s. Great sound approaching the Shure’s, but at less than a third of the cost. They are also dual driver ear phones that do a great job of sound exclusion via nice soft ear canal fit. But take them on the road and they catch the wind like a catamaran’s sails. These things actually amplify wind noise! No good. But great for off the bike.

Which leads me to the best solution I have found to date: a pair of Shure E500 PTH’s. This is a new model that replaces the Shure E5c’s and costs about 40% less. They have three drivers (two low end and one for upper register sound). And they seal even better than the E5c’s. Now I have the system in tune again: iPod+Shure E500+Pinarello = bliss.

Just how over the top extravagant are earphones like this? Yes, they cost around AUD$700. But! the ‘services’ you get from them last for years and years and the enhancement on offer to the already passionate experience of cycling is worth vastly more than the entry price for gear like this. Just give up all that other useless stuff like cars and apply what you save there to scoring your next ride to great music. After all, some totally sad car people spend thousands on ‘car audio’. And it always sounds like garbage. Cars are even noisier than bikes if you are honest. With an iPod and great noise isolating ear phones, you have a music making combo that is better than any petrol head can EVER come up with for their tin boxes at ten times the cost (for one percent of the quality). Plus those sad sad folk don’t even get the thrill of cycling; they just sit there ‘decomposing’ their fume boxes struggling to hear anything other than ‘boom boom boom’ (the bass bits).

Nope, we cyclists are uniquely privileged. We alone can take something akin to an audiophile standard sound system with us to enjoy on the road. Just reinforces the point that cycling is all about the journey. And the journey is so much better when scored to music.

Comments No Comments »


Picture this.

You are flying at 95km/hr down a long hill. Full racing tuck. Vision telescoping, the world reducing to speed on the limit. You are in total control, like on rails, a missile; bike and body one. The bike is in tune. You are the bike, the bike is you.

Then, just as you enter the curve out at the foot of the hill, the trees thin out and you enter a valley. This valley channels the wind. Sideways, into your wheel. Whack! The wind hammers the front wheel. Physics sets in. The front wheel starts to vibrate, viciously, side to side. Worse than a blow out, worse than hitting a hole. You are no longer in control. The bars vibrate side to side. Then the whole bike. You cling on; grasp the bars in a grip of death. But this makes it worse. The wobble wants to escape; but your grip holds it in. Now the whole bike is shaking; breaking, you are dead! You know your brakes cannot pull out of this; a skid would make it all so much worse. Search for a place to crash. Your bike is finished. So are you. Such is life.

But, somehow, you remember the advice. This is a death wobble. Physics at work, a vicious cycle of vibrations amplifying itself to your destruction. What did they say you do??? Loosen your grip. Relax !?!? You do. It stops. Back in the groove. Look collected. Look cool. No worries.

Shimmy and Death Wobble in bikes and motorbikes is an oscillation phenomenon caused by gyroscopic dynamics of the front wheel and positive feedback of the bike+rider.Sustained oscillation has two necessary components: An underdamped second order system and a positive feedback mechanism.The underdamped second order system is the nutation of the front wheel. An example of an underdamped second order system is a spring and mass system where the mass can bob up and down (oscillate) when hanging from a spring.The positive feedback mechanism is the bike+rider, approximating a second order damped system. At a critical bike speed, the front wheel nutation frequency matches the bike+rider natural frequency; if the bike+rider side-to-side system is insufficiently damped, the movement provides a positive feedback to the front wheel second order system, amplifying or sustaining the nutation. From Wikipedia

Comments No Comments »

Get Adobe Flash player