Thursday 21 May 2015

ALPENDINGLE: The hour record; how to build a custom, alpine gear cassette for a vintage 8-speed road bike and a 3 gear dingle-speed that does the job.


On September 18 last year, Jens Voight set the the first of the new UCI unified-rule hour records riding 51.115km in an hour, on a standard endurance track bike.



We loved the hour record in the 90s because of Graeme Obree and Chris Boardman, pushing the limits of technique and equipment with extreme riding positions and masochistic training regimens. The whole thing eventually got so out of hand that the UCI took the record back to Eddy Merckx's 1972 mark of 49.431km. They reclassified the Obree, Boardman shenanigans as something called "Best Human Effort" and restricted further attempts to riders using equipment roughly the same as Merckx rode. The boffins migrated to the International Human Powered Vehicle Association, where riders using fully faired recumbents pushed the mark out to over 90km. Boardman set a new mark of 49.441km in 2000, riding a standard drop bar, wire spoked machine, to prove that it wasn't all about the bike and Ondrej Sosenka pushed it out to 49.7km in 2005, to prove that it wasn't all about Chris Boardman.

Since then, the hour record has languished with no one seriously interested in what had really become an artificially restricted record for replica vintage track bikes.

Voight's effort, his final retirement performance as a professional rider, launched new rules for the official UCI hour record. The new record is for distance travelled in an hour using a bike that is legal for track endurance events under the rules in effect at the time of the attempt. In a fair but confusing arrangement, some of Obree and Boardman's records were reinstated, including the 56.375km "superman position" record set in 1996, but Sosenka's mark was set as the one to beat for new attempts because his bike would have been legal under today's rules.

The new hour record allows riders to compete using standard modern equipment and you could say that the new mark was set using a standard, modern, top professional rider.

Wikipedia gives Jen's Voight as it's first example of a  Rouler, a french term for a particular type of rider. Sometimes translated as "all rounder" sometimes as "non-climber". A Rouler doesn't have the short term high power explosiveness of a heavy weight sprinter or more compact puncheur, and is generally not small enough to be a specialist climber. They can be great team riders, and sometimes pull off a win in a heroic breakaway or solo effort. Voight is 190cm tall, he's not the most technically perfect time trial rider, but what he can still do, at 43 years old, is wind up to maximum power and consistently stay there, hovering around the limits of his physiological performance for as long as he needs to, then launch a final drive into the red zone to reach the finish line on the point of exhaustion. And Jen's special talent is the eternal unmeasurable of cycling, the capacity for suffering. His famous saying is "Shut up legs!"

One for the Roulers! Voight's new hour record was a great mark for the end of a professional career and launched a stream of new competitors. So far 7 attempts have pushed the mark out by just under 1.5km, with more challengers lined up to try including Bradley Wiggens who is resting from the grand tours to concentrate on track and olympic riding.


My qualifications as a "non-climber" are more modest, and have less to do with innate physiology and more to do with an unmeasurable capacity for chocolate.

I've got a reasonable level of fitness in my 40s, and I've always had big legs. So with a bit of re-training, even though I hadn't done any regular riding for nearly 20 years, I was able to keep up with the group on weekend rides around the river loop. That's Brisbane's famous, and mercifully flat training ride for everyone. But I'm also 180cm tall, and I like to eat. My leg muscles grew with more riding, but despite my slimmer face I didn't actually get any lighter. That's OK riding on flat land because most of your energy is used overcoming wind resistance not weight, but when Brisbane riders get bored with riding round The River, the obvious next thing to do is ride up The Mountain.



Mt Coot-tha is not a particularly big mountain. The loop over the summit and back is 9.4km and climbs only 217m, but it is steep with sections over 20%. The infamous Tour de France stage on Mt Ventoux climbs 1617m over 21.8km but is seldom over a 10% gradient. Inevitably I started out with a patient friend who knew the way.

I started too fast and boiled over on the first steep section, climbing up to where the road branches to start the loop.  A rest and a drink and we rode on, and again in the last 500m of about 2km of hard climbing, where it suddenly gets even steeper, I had to give up and sit on the side of the road, physically unable to turn the pedals over.

Although my problem could probably be solved by not eating chocolate in front of the TV every night, I decide to see if I could fix it with Gear Theory for Bicyclists.

sheldonbrown.com can tell you all about shifting patterns and the trade off between Range and Gradation. Between having a gear high enough for the fastest and low enough for the steepest terrain you're riding over, and keeping the steps between the gears small enough so that you can always find the gear you want without breaking your rhythm. Modern road bikes go for the obvious, by simply putting more cogs on the rear wheel. This is possible through design improvements like the freehub replacing the freewheel, allowing the rear axel to be made longer without breaking, and trade-offs with durability and maintenance like using thinner more flexible chains so the rear cogs can be put closer together.

Modern bikes have up to 12 cogs on the rear wheel, but my 1994 Trek 5500 only has 8. With the mix of riding I was doing going from fast flat riding, straight to steep climbing with nothing in between, what I really wanted was a cluster of close spaced medium to high gears with one, low survival gear to get me over the hill. I needed old school alpine gearing.



Every part of your bike will eventually wear out if you keep using it. You can build a whole new bike one part at a time replacing them. But the parts that wear out first are the ones that move the most, under the greatest stress, while most exposed to the elements, the chain and the rear gear cassette. It's handy for bicycle cdd maintenance if you know how to check for chain and sprocket wear and how to remove and install a cassette.

If you know that, it doesn't take much more to built your own custom bicycle gearing system with a personalised choice of gear ratios.

There are a few different ways to describe bicycle gears including how far the bicycle moves for each turn of the pedals, and the size of the front wheel on an equivalent penny farthing. Sheldonbrown can explain it and even has his own system. If we're just comparing road bikes, so the wheels are all the same size, and we don't want to worry about crank length, it's probably easiest to just count the teeth on the front and back gears. Remember it's the ratio of the tooth counts that matters, the front divided by the rear. A 40T front cog with a 20T rear (40/20T) is the same gear as a 50/25T combination. Small changes in tooth count make a bigger difference when you are using smaller cogs. A 2 tooth change is a sixth of a 12T cog but only a fifteenth of a 30T.

I started with the 53T and 39T front rings already on the bike. A smaller cog at the front is a lower gear, slower but easier to pedal up hill. Theoretically you can get any size you want, but they mostly come in a few standard set ups and they're not all interchangeable. When I swapped the 12-21T rear cassette, that I had been using, for a wide range 11-28T cassette, I had a low enough gear with the 39/28 combination to get up the steep sections on Mt Coot-tha. But racing around on the flats I often couldn't find quite the right gear, or the gears I wanted were in the wrong part of the range so I had to change both front and rear cogs at the same time or run the chain across a big angle from small front cog to small rear cog, which can cause wear and skipping.

I also had a super high gear, 53/11 that was really only useful going down hill at over 60km/h. Although that is easily possible on the Mt Coot-tha descent, it is neither very safe nor legal. So by taking apart a couple of cassettes, I made up one with the gears that I wanted, where I wanted them.












The different sized sprockets on a cassette are usually held together with a long narrow screw which you have to remove. When you make your own cluster you don't have to screw it back together, just stack the sprockets and spacers alternately on to the hub spindle making sure the right side faces out and the splines line up with the grooves on the hub. Pay attention to the spacers because they may not all be the same size.
















For me 3 is a magic number. A gearing ratio where the front cog has about 3 times as many teeth as the rear cog is a good, comfortable, flat land cruising gear.

After some trial and error, I ended up with a rear cluster of 13, 14, 15, 16, 17, 18, 21 and 28T. with the 53/39 front rings I can mostly cruise around on the big ring, playing with the closely spaced high gears, then drop the chain onto the small ring for the short hills near the river. When I get to the real climbing I put my head down, shift the chain onto the extra large rear cog, and grind till I get to the top.

There are a couple of reasons why it makes sense to have smaller differences in tooth counts between the smaller cogs in the rear cluster and bigger differences between the larger ones. One is the mathematical effect I mentioned above, a single tooth difference is a bigger proportion of a small tooth count than a larger one. The other is the different physics of climbing versus riding at speed. When you change down because a climb gets steeper, the load you are working against doesn't change because the combined weight of you and your bike doesn't change. But riding at high speed, most of the work is done against air resistance, when you change up to go faster the force you have to generate to go forward increases. If the gap between gears is too big you can find yourself spinning out in the lower gear but unable to keep pushing the higher one.

Sometimes I wish I had an even lower gear for climbing. But there is a physical limit to this game, set by the amount of excess chain your derailleur can take up (see here). Even though it's recommended not to shift into the small-small combination, with my set up I can do it without the chain going slack and falling off, I can just get into the the big-big combo without the chain being too short and seizing up or breaking something. I could take a risk and extend my gear range a bit further, if I could always remember not to shift into these extreme combinations, but I'm too likely to make a bad shift and have to stop and fix my bike, or walk home.





That was fine until I had to put my road bike into the shop to be serviced. I'm a pretty brave home mechanic, but I didn't feel like trying to get a worn headset out of a 20 year old carbon fibre frame. So while it was waiting for professional attention, I was left without a bike for riding the Cootha Loop.

In my previous experiments with 2-speed dingle gearing, I had only built bikes with a fairly small range between the high and low gear. I had been using 2 speed freewheels, with only a limited choice of sprocket sizes. By using a wheel with a multi-speed free hub and the same techniques I've just described, I could build a 2 speed bike with a high speed cruising gear for the flat lands around the river, and a super low climbing gear for the mountain.


Alpendingle Alpine-Gearing


The Alpen Dingle (actually a 3 geared "Tringle") has a 52 tooth large chain ring that pairs with either a 16 or 18 tooth rear sprocket to give a choice of two high gears for flat and rolling terrain. A 40/28T combination gives a low gear for climbing. You have to stop at the bottom of the mountain and change gears with a spanner of course, and again at the top when you are about to come down. The gears are matched so that the chain length is almost the same in the low and high gears. The axle can slide back and forth a little in the horizontal forks to accommodate the small differences.




Just check the brakes, and away you go. A couple of minutes behind, but at much the same a pace as I would be on my multi-speed road bike.

You can't get much simpler than that. Except that the modern track pursuit bikes being used in the new UCI hour record attempts are mechanically simpler than my dingle bike. Only one gear, no freewheel system and no brakes. The new bikes are more aerodynamic than the 1970s style wire spoked ones of the old record. But Graham Obree's rides showed us that even there, the rider is at least as important as the machine.

With all the advances in engineering and materials, training and sports science since Merxxs in 1972, there has been less than  6% improvement in the distance a top sports cyclist can ride in an hour. With new interest from some big name riders, it will be fascinating to see what happens next.

Sunday 16 February 2014

Crayzee-Eye vintage Dacordi, Sturmey Archer 2-speed kick shift coaster commuter: One Less Karma.

I've written a few posts about how to go fast. What makes a difference, apart from your own skill and fitness (overall weight of bike and rider, an aerodynamic riding position and good tyres), and what doesn't (just about every thing else). Going fast is fun, but  really, the main purpose of a bicycle is to make you smile!

These are images from the Kurilpa Derby which starts under the bridge near my house and finishes with bike polo and novelty races down the main street of West End.






Here's someone else's blog post about that.



This post is about a bike I built from an idea. It's about the way bicycles work and the way the universe works. It's about why you may be able to have what ever you want, but you can't neccessarily have everything you want. It's the story of the Crayzee-Eye vintage Dacordi, Sturmey Archer 2-speed kick shift coaster commuter. It all starts with these rims....


I posted this picture before, when I was looking to replace a wheel I broke in a drain cover. These rims made me smile when I saw them.  They're velocity deep V image rims with a pattern called "Crayzee-Eyeballs". Velocity started as a small company making bottle cages and then rims in my home town of Brisbane. Like many Australian manufacturers, they have since moved their business overseas. Unlike most companies that go looking for cheap labour and production costs in Asia, Velocity have moved to Jacksonville Florida.

They don't make image rims anymore. A brief, bright moment in cycling fashion, now past. The rims were made in Australia, then shipped to the US to have the image coating applied, then at least some were shipped back to Australia to be sold. The company stopped making them and they started to go out of stock just when I started looking for one. But I managed to find one of the last ones in stock.

Is it Karma?

When I first heard of Karma I understood it mostly as the way people who believe in reincarnation explain the influence of one life time's actions on the circumstances of the next. But now I understand it encompasses a more subtle concept as part of the hindu/buddhist doctrine of cause and effect.

The philosophers of the ancient east believed that things happen as they do because of the things that have happened before them. In fact every thing happens because of every thing that has happened before it. We exercise free will, but our choices have consequences whose effects echo on through time.

In the classical European religions, there was a different idea. The capricious gods sent good and bad fortune to humankind on a whim. Often with callous disinterest, as they dealt with their own godly concerns, and barely if ever susceptible to human understanding or influence. Later they were replaced with a god who was personal and vengeful, even though it's motivations were mysterious, but in the enlightened, secular cosmology that followed, the idea of randomness persisted and the mathematics for dealing with unpredictable events developed the "laws" of probability. You know. Like tossing a coin.

But that doesn't sit very well with the idea of a clockwork universe. There's nothing inherently unknowable about tossing a coin. All the movements of it's spinning flight are controlled by fairly simple laws of physics. If we could precisely control and measure the position of every thing involved, and the force exerted by the finger on the coin, we should be able to predict it's path. But we explain randomness mathematically as if events had no cause at all, as if, all things being equal, the result could just as easily go one way as another.

Surely if we are confused by the universe it must be because we don't have enough information. If we could just define and measure and keep account of everything and work out the rules of the machinery that governed it, we could master the universe. If we can't predict and control every thing in our lives it must be because we are not trying hard enough.


That's what I used to think, but another idea about unpredictable events had been developing amongst mathematicians, going back to the late nineteenth century. The idea developed slowly at first, but picked up from the 1960's with the development of electronic computers ideal for repetitive calculations.  By 1987 there was enough for a popular science best seller and James Gleick's book about Chaos theory  came out just in time for the Second Summer of Love.

After that I saw the world differently.





Chaos Theory blew our minds with concepts like the butterfly effect and the wild visuals of mandelbrot sets. To me, the transformatory insight from chaos theory was that deterministic systems can behave unpredictably. That means that even for a simple mechanical system, governed by clearly understood laws of physics, whose behaviour can be described by a few algebraic variables and the equations that describe the relationships between them, it can be impossible to predict the state of the system more than a short time into the future. We used to think that there were two ways things could go in the universe, deterministic and predictable, if you knew everything about what was going on you would know what was going to happen, and random, no way of telling. But chaos was a new, third way, unpredictable but structured, deterministic but incomprehensible.

In the mathematics of chaos theory, complex system, like the weather or the world economy, can be modelled as shapes in a multidimensional phase space. The mathematical variables that are used to describe the measurable aspects of the system can be plotted on  different axes of a graph just like the y=2x+c graphs from high school, except the simplest chaotic systems have at least 3 variables and would have to be graphed as a 3D shape in space, instead of a line on a piece of paper. More complex systems, with 4 or more variables, are represented by virtual, higher dimensional shapes that can only be draw in hyperspace.

Truly random behaviour is completely unpredictable, but chaotic behaviour is often constrained by a strange attractor, parts of the system's possible phase space where the system is unpredictable from moment to moment, but tends to trace out a defined shape within the space. The detail appears random but we can understand how the system works overall.

It turns out that truly random behaviour is extremely rare in our universe's natural systems. Things are either ordered and predictable like clockwork, or chaotic. Not random, not predictable, but still structured and shaped by the laws of cause and effect. Things don't happen without a reason. What you send out comes back to you. It's karma. When I made the decision to use those "Crayzee-Eyeballs" rims, I didn't know exactly what the end result would be, but I knew it would be shaped like a bicycle.


From the initial intention in choosing the rim, one thing lead to another.

Firstly, the Deep-V rim is not all that deep. The main feature of the bike is a 30mm wide strip of eye balls. The  rims were available with a machined braking surface for use with a conventional rim brake, but that would take away about a third of the pattern and ruin the look. So I went for a matching, black Deep-V rim with a braking surface on the front and no rim brake on the back.

The cool and hip thing to do would be to run a fixed gear drivetrain to control the rear wheel. But I live on a steep hill, I don't have a background in track cycling, I'm entering my late 40s and I want to coast. I tried riding a fixe on the road and I didn't love it. I'm also aware of the danger, not just of falling off from bad riding technique, anything caught in the drive train will bring the bike to an instant stop! You can even loose a digit spinning the wheel in the workshop. But riding around with a freewheel and no rear brake is only cool until your front brake fails, so I wanted either a disc brake or some sort of hub brake. 

Disc brakes were new and exotic when I was riding mountain bikes in the 90s and I never had the chance to work on them. For a variety of reasons they are now about as new and exotic for road bikes as they were for MTBs in the 90s. So to use disc brakes I would either need a 29er style MTB frame, or some kind of new and exotic hybrid, road or cyclo-cross frame. Not really the look or price range I was thinking of.

Some kind of drum brake, or coaster brake, like the back pedal brakes on kids bikes? Crazy or "crayzee" but it makes sense. It's karma.

Now hub brakes are usually fitted on cruisers and utility bikes. These usually have sturdy wheels with a standard 36 spokes, but the "Crayzee-Eyeballs" rims are a "high-performance" style, 32 spokes. As far as I could find, at the time, there was only one shop in the world that could sell me a 32 spoke coaster brake hub junkyrustybikes.co. When I saw that they had a 32 hole version of this... I new it really was karma...



That's a Sturmey Archer S2C hub. In my head I hear the words "Sturmey Archer" in my father's voice, remembering the stories about old bikes he told me, while showing me the basics of fixing mine a long, long time ago. The venerable company, established in 1902, was going the way of most British engineering when it was bought by Sun Race in 2000 and now has a new range of products manufactured in Taiwan. This one is a 2 speed-kick shift coaster hub. It has a direct-drive low gear and a 130% overdrive, engaged and disengaged with a small backward movement of the cranks. The brake activates with increased backwards pressure and stops the wheel without touching the rim. No cables or hoses, no handles to mount, just that extra anti-rotation arm to clamp onto the left chain stay.

Then I needed a frame.

There are lots of old bicycle frames on ebay or wherever at any time, but not too many in my town, and even I'm not silly enough to buy an old frame without even looking at it. I needed horizontal dropouts or track forks and a frame spacing that would suite the narrow 116mm rear hub. But it didn't take long before the right frame came along.

Some one had an old italian track frame under their house that they had lost interest in. The 58cm seat tube was a little smaller than I have been riding but a smaller frame would show off the wheels better. The chromed front forks had been drilled for a brake, but the back hadn't. The frame was nice and clean with no braze ons or guides for cables or controls. It had daccordi, stamped into the seat stays, and a flying-D on the sloped fork crown. The head set said "suntour supurbe track" and the bottom bracket turned around alright but needed a bit of cleaning, some paint on one side showed that it wasn't completely removed when the frame was resprayed white. I liked it. I probably paid too much for it. The rear frame space was exactly 116mm.

I'm not going to try to tell you how to build wheels. I'd never done it before and probably won't ever do it again. When I got the "Crayzee-Eyeballs" rim, it was built onto a velocity, sealed bearing front track hub. I took that wheel apart and used the hub to build a front wheel with the black Deep-V rim. Using a radial spoke pattern made it relatively easy, but I still had to undo parts of it a couple of times. Then I stepped up for the rear wheel and built the fancy rim onto the Sturmey Archer hub using a stronger three cross pattern, thankfully no dishing was required.

 


These are the instructions I used but I can't honestly recommend that you do it yourself because of the potentially dire consequences of catastrophic wheel failure. If you do give it a try here's my one hot tip. It can be quite awkward to get the nipples that hold the spokes lined up with the inner holes of a deep profile rim, without them going missing inside and rattling around till you can shake them out.



Fine surgical instruments might help.



But then I thought to thread them backwards onto a spare spoke to feed them through. I wish someone had told me that one before I started.

The bottom bracket was a bit of a surprise. When I cleaned it up I could read "nadax" and also "FAG"?


It turns out to be a swiss, servicable, sealed bracket, with labyrinth seals. Which might have looked like this, if I'd taken it completely out.


But the alloy that the threaded casing is made from is quite soft, as you can guess from the damage around the tool notches in the photos, and I didn't have the special tool that the manufacturer recommends for removal. The right hand side thread was stuck hard and painted over and I actually wasn't quite sure which way to turn it.



I pulled it apart enough to find this inside. Then I cleaned it up put on some new grease and put it back together.


The problems getting the bottom bracket out, went along with the idea that I might see how the bike rode before I spent extra money on a paint job, to help make the decision to leave the frame as it was, chipped white, with chrome forks.


I put the "supurbe" head set back together, and the rest of the parts were simple, shiny, steel. No name parts from Taiwan, and an old saddle I had taken off one of my wife's bikes. (One of the bikes of my wife, not the bike of one of my wives.)



Luckily I had some short reach caliper brakes that lined up with the rims, if I adjusted them as short as they would go, and turned the brake blocks upside down. The old track frame was made with minimal clearance between the wheels and the frame, and not designed to have any brakes at all. With the front brake mounted, the gap was so narrow that my final choice, what tyres to put on the bike, was limited to what I could find that would actually fit. These are 700 x 20mm, Michelin Pro4 service course clinchers. There's about 2mm between the tyre and the brake arms.


Anyone giving you sensible advice about building a bike would tell you to start by considering what type of riding you are going to do. They wouldn't tell you to get fascinated by some shiny fancy wheel rims, and build a bike to show them off. Now that I'd built the bike what was I going to do with it? Had my chaotic approach to bicycle design given me something I could actually ride, or was it only good for hanging on the wall, or pulling apart and starting again?

At first I put some funky little mousachioed track style handlebars on it and I found it a little "over responsive", almost uncontrollable at low speeds or when riding out of the saddle. But with a bit of practice and some wider, road style drop bars, I started to master it and even appreciate the maouverability.

The 2-speed coaster hub took some getting used to, until I learnt to not let my feet turn backwards at all while I was coasting. I started to like the quick and definite shifting without having to take any weight off my hands. If your'e not sure which gear you are in by feel, you can tell from the sound the hub makes.

The skinny tyres give you a great "feeling for the road"... every little bump! They look fast, they feel fast, but that might be an illusion. They're not fast to get on and off the rims and usually need 3 tyre levers. (There is an alternative for converting a tight clearance road or track frame using slightly smaller 650B wheels, which would create another problem of finding non-standard size tyres.)

It was a fun bike to ride. I had thought at first, that I wouldn't use the coaster brake much, but would mostly use the rim brake on the front wheel, but I soon got to like it so much, that I usually only reach for the hand brake on down hill corners. So I put the lever in the handle bar drops.

It wasn't really the best bike for weekend group rides. The 2 speed hub, with only 130% range would leave me either spinning out on the flats or struggling on the climbs, and dropping off the back of the group.

The bike would look good leaning on a post outside a hip cafe, but it's minimal lines, with nowhere to mount accessories or luggage, weren't very practical for running down to the local shops, picking up the take away or carrying kids around.

The other ride I regularly do is my commute to and from work. Two or three times a week, depending on my schedule and family logistics, I leave the car behind and take a bike to work. On the map, work is only a couple of kilometers away, but to avoid the big hill in between, and to get in a bit more riding, I head the other way and follow the bend of the river around to my destination.

On the banks of the river's city reach, the split personality of Brisbane cycling is on display. On the South side, the bike path runs past the Gallery of Modern Art and the Museum, State Gallery and Performing Arts complex, into the South Bank Parklands redeveloped from the World Expo 1988 site. There's the "Brisbane Eye" giant ferris wheel, a sandy, artificial beach open for swimming and, except in the very early morning, hundreds of people walking around, buying ice creams, taking photos of each other, riding in pedal cabs and promenading on shiny cruiser bikes and wobbly roller blades. The speed limit is 10km/h, and is rumoured to be occasionally enforced by police with speed guns.



On the North side, the Bicentennial Bikeway efficiently separates the cyclists from the traffic and the pedestrians, and carries a steady stream of commuters down, under the Riverside Expressway where funky urban graphics direct cyclists past the old quays and beside the mangroves to their city destinations and the Gardens Point university campus. A ruthlessly efficient Mr Hyde, opposite the South side's sunny Dr Jekyll.



The South bank is the more direct route to work, but after I was T-boned by a giggling youngster on a retro step-through coming, out of control, off a spiral ramp, I decided to ride on the other side of the river.

I ride from home, down and around the sweeping bend of the river, then climb, over the Go Between Bridge, and follow the almost pedestrian free, bikeway to the car free, Goodwill Bridge, which takes me back to the South side near my work. It's a shade over nine and a half kilometers, mostly flat, except for the two short bridge climbs and the slope from my house to the river, and mostly on good smooth dedicated bikeways.

And the Crayzee-Eyeball bike loves it! The twitchy little track frame flicks around obstacles and through the gaps between pedestrians in the shared spaces and then settles down to roll fast and smooth on the bikeways. The 2 speed hub lets me hit the bridges and change down without having to move a finger or shift my riding position. The skinny tyres are ok on the smooth bike path surfaces and the heavy duty 1/8" drive cog and chain are more durable than those used on most multi speed bikes. That suits a frequently used commuter bike, and with the gears and rear break enclosed in the hub, relatively weather proof and maintenance free, there's a pretty good chance the bike will be functional when I pull it off the rack, running for work in the morning.

I was very happy riding to work with my bag over my shoulder, but as the weather got warmer my bag started developing a salt crust from lying on my sweaty back. My clean, uncluttered frame didn't have any fixtures to mount a rack, but I'm obviously not  the only one with that problem. I found one that straps to the seat stays with a locking ratchet. "Thule Sweden", it says on the top, and underneath "Designed in New Zealand". Sweet as Bro!

Here's a picture of the bike, set up with luggage deck'king bright light with top tube battery pack, blue break cable, a red bell mounted under the stem and matching anodised chain ring bolts.

Crayzee-Eye, vintage Dacordi, Sturmey Archer 2-speed kick shift coaster commuter.



Friday 22 November 2013

Hot Stems

Since I wrote about how sexy the "droopy 7" stems that fit old style threaded headsets are, and how difficult it is to raise the handle bar height on a modern bike with a threadless headset, I've been seeing things like these.





Which only proves I was right in the first place.

(shop here)

Thursday 7 November 2013

Cool Bikes at Work.


I work in a big organisation on a campus spread across a number of buildings. I have a single office in a small peripheral building, so when I'm at work that's where my bike is. But a lot of people work in shared spaces or public areas and leave their machines in the bike parking area under the overhang of the main building. I often take the chance to walk through and see what other people are riding.

All bikes are cool, but these two were cool enough to stop and take a picture. I only saw them once each, so maybe they were visitors, or maybe these are what someone was riding while their other bike was in the shop.

This one has the unmistakable Raleigh head tube badge. The labels say "Picnica by Bridgestone". Google says that's a seriously cool piece of retro kitch. A small wheel, folding bicycle sold through the 1980s, with a belt drive, popular predominantly in Japan.

The helmet tells the rest of the story.



This one is practically brand new. The 26" wheels and the geometry remind of the old school mountain bikes I used to ride. The leather saddle with large copper rivets, the comfy commuter hand grips set in an insanely low riding position, says he's a real rider's rider. (It has to be a boy.) Unfinished alloy frame, thoroughly modern hardware, fixed single-speed drivetrain and a single, front disc brake with a big, pink rotor guard built into the fork. The light, plastic mud guard is Dutch. Maxpowercycles is a German maker of polo specific bike frames. See if you can mail order one.



Saturday 7 September 2013

1994 TREK 5500 OLCV: It's all down hill from here.

My passion for cycling had been rekindled by a jellybean single speed my wife bought me online. I tinkered with the drive train to make a two speed dingle bike. Having got the bug, I rebuilt a 1970's ten speed racer, like the one I used to ride to school.

I'd convinced a couple of friends to go riding with me, but it turned out they were fitter and stronger and lighter and better riders than me. Rather than resort to training or diet, obviously I needed a better bike, or at least a lighter one.

For $9,900 I could be on a new pinarello dogma, or I could get a second hand alloy framed malvern star on bikeexchange.com.au for $399 that would do the job quite well, with a carbon fork!


But my heart said TREK 5500 OCLV (1994)...

In 1994 I was living on a Mongoose IBOC rigid mountain bike, and discovering professional cycling and the Tour de France in nightly 30min highlight packages on SBS.

Coincidentally, the years of my mid twenties coincided with the peak era of human culture and technology. Did that happen to you too? From there it has been a long slow decline into chaos and this bike is part of the story of that decline. This was Lance Armstrong's bike.

You can read the history of the OLCV frameset here, and a lot more TREK history here but basically the company started building carbon frames using the "Optimum Compaction, Low Void" technique in 1992, they built my bike in 1994, they signed up Lance Armstrong in 1997, he had the fastest time in the 1999 Tour de France and from that year, there is a 7 year gap in the official records with the competition being judged so corrupt, that no winner could be declared. For almost all of that time, apart from some changes to the forks and steerer, and tweaking the carbon recipe, Lance was riding a bike essentially identical to this one.

Lance Armstrong had a lot of fans once, but I was never one of them. It wasn't the drugs and the blood transfusions I objected to, it was the bullying and the bad sportsmanship, the corruption and the ruthless pursuit of winning without any consideration of grace or style. I miss Marco Pantani. He was the last rider to win the Tour de France before it sucummbed to Armstrong's relentless grind. His 1998 win may or may not have been done "without assistance", but it was done with style. Having prevailed in the Giro D'Italaia that year, Pantani started the Tour 4 minutes behind after the opening time trial, by the end of the Tour he had turned that into a 4 minute lead by his audacious and agressive riding in the mountains. Sadly, having been caught up in the doping scandles that followed, he died with a cocaine overdose in 2004.

In my memory the 1990s was an ideological battle ground, a fine-de-siecle struggle between different visions of how an individual might exercise personal freedom and power in the new millenium. The conflict between de-regulation and anarchy?


 

 If Lance Armstong was the Gordon Gekko "greed is good" face of the 90's in cycling, then Marco "Il_Pirata" Pantani was a fire starter... a twisted fire starter.


In this video from the 2000 Tour de France, Pantani now in the late part of his career, has caught Armstong's leading group at the bottom of Mt. Ventoux and attacked several times, starting to break away when Armstrong responds. They set a blistering pace, up the climb as they swap leads and a few words (racing without helmets). Did Armstrong pull up at the end and give Pantani the stage victory? Whatever he meant by it, Pantani found him offensive! He withdrew later in that Tour and never rode it again.


You can see a longer version of Armstrong and Pantani on Mt. Ventoux, with commentary in Italian at http://www.youtube.com/watch?v=_bMBTRqctF0.


In 1994 this TREK 5500 cost $4,500 and the old man I bought it from had been a younger man, pretty serious about his triathlons. The bike was well looked after while it was ridden and was in good condition except for the tyres and a few spots of rust on some bolt heads. It had a full Shimano 600 "tricolor" group of components, including head set and hubs built onto italian Ambrosio rims.



The 5500 OCLV was one of the first bikes with a monocoque carbon fibre frame. Carbon fibre compounds are nearly ideal materials to make bicycle frames. Their high tensile strength, low density and  stiffness (low Young's modulus) makes performance bikes significantly lighter than any other material. It's the ideal material for a bike that you are actually riding, but because of it's brittleness and vulnerability to direct impact it probably isn't the ideal material for a bike that you are trying to take apart and pack into the back of a small car, or the ideal material for a bike that you are locking up and leaving out in the street overnight, or banging around in a crowded home workshop. (Put the spanner down before you pick up the frame.) When it does break the failure tends to be sudden and catastrophic, so it's certainly not the ideal material for a bike that you are crashing, or trying to fix afterwards and get back on the road, but for riding fast and hanging on a hook in the garage it was the right choice. I believe some people would get a second hand carbon frame xray'd to look for hidden cracks. I looked the old man in the eye and believed that he'd never crashed it.

Early carbon fibre bikes were made from pre-formed carbon fibre tubes glued into alloy lugs. This Alan frame is a particularly beautiful example. It's got an alloy right chain stay, where impact from the drive train can cause damage, and alloy forks. (As opposed to the later trend for alloy frames with carbon forks.)


The OCLV frames were built in one piece in a mould and compressed from the inside with an air filled bladder. That saves more weight and allows more variations in the geometry and the thickness and composition of the materials in different parts of the frame. You can make shapes like this...


Just about everything on the bike: gears, brakes, cranks, rims and headset, is marked SHIMANO 600, mostly with a three coloured rectangle. 






Shimano make about half of all bicycle components sold and their marketing strategies are as well developed as their engineering. They cover the whole market from children's bikes to the top of professional racing, with multiple product lines and yearly model upgrades. This version is sometimes nick named the "600 tricolor group". Sheldonbrown.com tells me that the 600 group was later designated "Ultegra" and was the second level of road bike components below "Dura Ace".

I'm not sure if that necessarily means the high level group is better. It may be lighter and more race worthy, but not always as robust and long wearing, or easily adjustable and servicable.

There are bicycle enthusiasts who know much, much more about these things than I do, and they have on line forums. One of the boffins here says:

"This is one of my favourite groups of all time as it is well made, shifts extremely well, and is rather tough to boot."



In the early 90's combined brake lever / shifters (brifters), like this STI system were a signifiacnt innovation in bicycle controls. In these early models, the gear cable comes out sideways. Modern ones have it hidden under the bar tape along with the brake cables for improved aerodynamics, but otherwise they function much the same. They are more complex than the simple levers that came before them, and unlike most bicycle innovations, they are heavier. Armstrong is said to have had a climbing bike set up with a brifter for the rear derailleur for quick shifting and a simple down tube shifter for the front, to save weight. Repair and servicing are a problem. There is probably more chance of repairing early models than later ones. The manufacturers would be happy for you to purchase a new set when the old ones stop functioning.

Mine were not shifting smoothly when I got them. I did a bit of reading on line, and as advised, put a can of spray oil in all the openings I could find and repeatedly worked the mechanism back and forth. Now they are perfect every time. 

It took a bit of fiddling to get the gear cables the right length for the index shifting to work. My old mountain bike had Deore XT thumb shifters with index shifting. They were fitted with a little mechanical switch that would disengage it. When the cable stretched and the gears went out of alignment, I just turned the index shifting off.

The TREK has this Trim Tab on the down tube. You can adjust the rear derailleur cable while you're riding!

 

A sealed cartridge bottom bracket with a square taper crank fitting means I already have the tools I need for servicing, it's compatible with just about everything, and it can be easily replaced if I have any trouble with it. I assume this one is about 20 years old, and it still works alright. Modern bikes can have a variety of mutually incompatible bottom bracket / crank systems with, arguably, very little performance improvement except for some ultra lightweight, or extra strong off road applications. With the old square taper fittings, you have to tighten the crank bolts from time to time or they'll squeak, or you can wait till they squeak and then tighten them.



Eight rear sprockets is enough really... isn't it? It's a question of range versus gradation.



Look at these pedals! 




Clipless pedals, confusingly, are the ones you clip in and out of. They replaced cage-like toe clips and straps (which are still commonly used by track riders to bind their shoes to the pedals). These LOOK pedals quickly became the standard, and essentially still are, although the design is out of patent. The latest models are a bit lighter.

The coolest thing about these ones is that they are labelled D for right and G for left. They are French.

The other common type of clipless pedal is the SPD system (on the right).


These are more commonly used on mountain bikes, and by tourers and commuters, because the smaller cleat can be recessed into the sole of the shoe to make walking easier.


I found some LOOK compatible cleats that fit my old MTB shoes. It looks a bit weird but it does work.  It feels like the larger contact area helps transfer power to the pedals and I never accidentally pull my foot out, like I sometimes do with the smaller cleats, but I can't walk properly in them.



The old man I bought the bike from was a giant. He had the seat way up and the handle bars low and extended out the front on a long stem. I was a bit worried that the bike might be too big for me. It was advertised as 62cm, that's the length of the seat tube up from the bottom bracket. That is the right size for me, using the old Cinelli formula of 32 to 34 cm less than the height of the rider's femoral head. But bicycle sizing and fitting is a complex and controversial art. Sheldon Brown knows everything and says that the top tube length is the most important dimension in getting a good fit.

It was raining when I went to look at the bike.  I didn't even try to ride it but I measured it up and decided I could get it to fit me. I hadn't anticipated how far forward the natural hand position on the brifters is, but by fitting a short stem and a pair of modern compact handle bars (deisgned for Rapid Hand Movement) I managed to get everything back into a relaxed version of my early 90s riding position.


The problem with going for a smaller frame would be getting the handle bars up high enough to be comfortable, especially for an old man buying a second hand bike. I'm 45, I'm not as flexible as I was and I want my handlebars and my saddle pretty much at the same height.

The Japanese company Dia-Compe patented their Aheadset® threadless headset in 1990 and they gradually became the standard for almost all bikes.

This bike has an older style threaded headset. You adjust the height by unscrewing the bolt on top (NOT the big nut around the bottom of the stem!) and sliding the stem up and down.



With this style headset, if you can find a stem with a long enough vertical quill section, you can extend the handle bars up as far as you  like...


which is why you still see them on kids bikes and upright cruisers.

With a threadless headset, you can adjust handle bar position by fitting a different size or angled clamp on stem. If you want extra hight, you need to install a set of forks with the steerer left long, the stem position can then be set by adjusting the headset stack height with spacers or clamps. Extreme variations include this...


and this!!


(Read more about this Sheldon Brown special here.)

I don't know what sort of stress that puts on the steerer. It's normally a fairly short tube attached to the front forks and completely hidden within the bicycle frame, headset and stem hardware.

My carbon fibre forks are mounted on a steel steerer, which should bend or buckle before it breaks. In 2001, TREK changed to a lighter, aluminium alloy steerer and later to carbon fibre, both of which are more likely to suddenly snap. Want to see what it looks like when that happens? Here's George Hincape riding a TREK OCLV in the 2006 Paris - Roubaix classic... That's essentially the same bike as mine, except for the steerer and headset system.


He's putting his life on the line in the quest to sell you a better bicycle.

Some say the threadless headet is more crashworthy, with less sharp angles to impact on. The alternative theory is that the expansion wedge system holding the stem quill in the threaded headset, will give way with less force than the handle bars need to penetrate your abdomen!

I'm prepared to accept that the threadless headset system is lighter, eaisier to adjust with smaller tools, and fits a bigger range of modern handle bars than the old threaded headset. The latest development in headset technology is the integrated headset, where the bearing surfaces are part of the frame itself, instead of separate components pressed into the head tube. This is no improvement at all! (See what head set guru Chris King has to say about them.) There might be some appeal to a professional time trialist, who is looking for marginal gains in weight and aerodynamics and whose sponsor will give them a new bike for next season, but for most riders the advantage is to the manufacturer, with fewer components and assembly steps and a system that can't be effectively serviced or replaced. That means you need to get a whole new frame when the headset bearing starts to wear out.

Since the 90s, the trend (possibly influenced by mountain biking and bmx) has been towards smaller framed bikes with longer seat posts, sometimes angled top tubes, and stems that slope up from the top of the head tube to the handle bars. This may make the frame marginally lighter and possibly stiffer. But I like the style of the old "droopy 7" quill stem. This design dates from a time when bicycles were sized much bigger, even with top tubes too high to comfortably stand over. The drop in the stem allowed the handle bars to be mounted below the level of the top tube if desired.

It's sad to see the fall of the Droopy 7 handle bar stem. It may not be as technologically advanced as it's lightweight successor, but too me it was the most beautiful and sensuous of bicycle components. When I'm bent low down over the bars, dripping with my own moisture, panting hard, with my tounge hanging out, I don't want to be looking at a stubby, over eager, clamp-on stem with a pop top, thrusting up in the air, bursting with seams and joints and exposed bolt heads.


I'd rather see the languid lines of something smooth sleek and sexy like this, enticing me to go harder and longer.


Now I'm not seriously suggesting that the 1994 TREK 5500 was the indisputable high point in bicycle development and that every thing that has come after is either a marketing gimmick or a backwards step. If someone gave me a new model Pinarello Dogma or any other high performance road bike, I wouldn't turn it down. But I think if you're looking for David Brailsford's marginal gains, you also need to think about marginal costs and opportunity costs. For less than 10% of the cost, and a few hours in the workshop, I've got a bike that comes close enough for a casual Sunday ride. At least if I can't keep up with the group I know It's my fault not the bike's. And the money I didn't spend on that bike can be spent on another bike. There are so many expensive machines on the road these days, with people upgrading, giving up, or accidentally buying the wrong size, there must be some real bargains in the second hand market.

But in the mean time, here are some more smokey back lit photos of my new 20 year old bike...






...And more of the fearsome and beautiful pirate of the 1990s, Marco Pantani.