i don't know how many of you regularly read cyclingnews.com (if you don't, you should) but there are many interesting items of correspondence on the tech letters section which have been most enlightening.
as a self confessed wheelaholic, recent discussion about super duper wheels at least let me know that not everybody is seduced by the marketing hype and/or fashion. however, one letter laid bare somebody's misreading or non-reading of the instructions in the box.
i have never fully understood the necessity to build wheels, particularly front wheels, with a radial spoking pattern. the notion that such a spoking pattern reduces drag appears to be a total myth. for starters, very few of us pedal fast enough for any reduction of drag to be a major factor. disc wheels might just have an effect for folks such as armstrong, millar et al, and conceivably so on indoor tracks. but since most of us are as concerned with crosswinds (try cycling on islay) as with headwinds, forward drag reduction isn't the advantage it may appear.
since the fastest part of the wheel is the rim (i'm pretending there's no tyre for this simile), then the spokes enter the rim in the same way on a radially spoked wheel as they do on a three cross. granted the spokes are shorter, and there may be some saving in weight, but i could probably save more by getting a decent haircut. however, to return to the cycling news correspondent, he stated that his front wheel was built radially on to a campag record hub, and after not a lot of miles, the hub flange started displaying a rather distressing crack - the flange had started separating from the hub body.
the surprising fact was that the writer was blaming the hubs. now i have no recollection as to whether the wheel was built by the correspondent or by his local bike shop, but somewhere along the line, somebody didn't read properly. for those who have bought nice shiny new campag (and for all i know, hubs made by shhh
you know who). the piece of paper included within the box, normally written in several languages distinctly says and has an accompanying warning graphic, that these hubs are not to be built into wheels using a radial spoking pattern. campag state that it voids the warranty. if it was the bike shop that built it, they ought to be shot. customers can demand what they want, but they should also have such information pointed out and all liability passed to them. since this chap expressed such surprise that his wheel was disintegrating we shall assume that this info was not pointed out.
however, we arrive back at the why. radially spoked wheels are regarded as 'cool'. as indeed are snowflake pattern, one or two of which i have built in my time. (for those unacquainted with such stylish wheels, the spokes follow the standard three cross pattern, but before the 'third' spoke enters the rim, it twists round the last spoke crossed. the resulting wheel looks like a snowflake). however, such wheels only look cool when the bike is stationary and assuming that we buy our cycle jewellery in order to pedal as fast as possible (don't we?), what use is there in building wheels that only look good when the bike is stopped? particularly if there are no advantages when they are rotating.
hope industries, producers of particularly neat hubs, produce a front hub specifically for radial spoking. the standard hub flange is not designed to accept the forces placed upon it by spokes that go directly from the flange to the rim. three cross, four cross, and even two cross, provide a degree of comfort - suspension if you will - and the forces are lateral, not radial. wheels have been built this way for many a long year, only the advances in spoke and rim rechnology have allowed the reduction in spoke count from a standard 36 to a more common 32 and from four cross to three cross. if you look at campagnolo's climb-dynamic wheels, and even mavic's ksyriums, (ksyria?) the hub flanges aren't thin and narrow like standard hubs, but thick and boxy, more than adequate to accept straight pull radial spokes and resist the more abnormal forces placed on such wheels. i have been on record in a previous post positing that wheels such as campagnolo climb dynamic, mavic ksyrium et al are mainly radially spoked using straight pull spokes because manufacturing is a darned sight easier than it would be if they were produced using convential patterns.
some of these wheels do indeed lighten up the overall weight of the bike, such as campag hyperons, but since they have carbon rims and are sprint only (tubulars) and cost about a thousand pounds, they darned well ought to. checking mavic's website for weights of this year's cosmos wheels, they are still around 1800g per pair - not a whole lot less than a good pair built on record hubs, three cross with a decent set of mavic rims and double butted dtswiss spokes. it's also a darned sight easier to repair a standard wheel and get spare spokes. if somebody drops in here this summer with a broken ksyrium wheel, the best i can do is replace it. i don't have the tools or the parts to repair one, and there may well be a number of bike repair places in a similar situation. then again, who's going to go touring to the islands on a pair of ksyria? surprising to relate, my reader and i cycled to dublin several years ago and his front wheel was a zipp 440 with about 16 flat bladed spokes and a deep carbon flange wearing a vittoria corsa cx tub. and he broke a spoke in the back wheel which was conventionally spoked. the zipp survived the trip unscathed.
however, the pros that use these things get new ones, no questions asked, when the first one breaks. and it's the fact that they use these things that makes us all want to buy them in the first place. sometimes tried and trusted is best.
but keep your eyes open just the same, and read the tech letters on cyclingnews.com
on a slightly different note, my regular reader will have noted the addition of a 'colnago c40' rollover to the left. this contains a reprint of a recent article featured in cycle sport magazine, which they were very kind to let me present here (because i'm a colnago geek)
i have been asked to add the following link to the post by wheelygoodcause. they're a cycling club dedicated to arranging epic rides for charity and do not charge charities for the pleasure. They ride because they want to, and the next ride takes them from st malo to biarittz and then across the raid pyrenees. so i have. and here it is.
Remember, you can still read the review of 'the dancing chain' the utterly excellent book on the history of the derailleur bicycle by clicking here
any of the books reviewed on the washing machine post can probably be purchased from amazon.co.uk or amazon.com
as always, if you have any comments on this nonsense, please feel free to e-mail and thanks for reading.
this column almost never appears in the dead tree version of the ileach but appears, regular as clockwork on this website every two weeks. (ok so i lied) sometimes there are bits added in between times, but it all adds to the excitement.
on a completely unrelated topic, ie nothing to do with bicycles, every aspect of the washing machine post was created on apple macintosh powerbook g4, ibook and imac computers, using adobe golive 5 and adobe photoshop 7. needless to say it is also best viewed on an apple macintosh computer.