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Cardboard Box 

Labour Weekend, so my wife thought a good plan would be an expedition with some Danes to the top of Mount Arthur in the snow and promptly set off for the hut. Therefore I made a cardboard box and Mr McLeod, who isn't Danish, wasn't consulted and had organised a recumbent ride instead, made a tailfairing and Mr Schroder made a fork jig. To each of us our accomplishments: some climb mountains, some make tailfairings, some make fork jigs. And I make a cardboard box. - As a matter of fact I've been meaning to make the box for a while because the old one was getting worn out - it's on the back of the shopping trike and needed to be a whisker bigger because of the statutory size of New Zealand juice bottles, which prevent crisps and milk and grapes being bought at the same time. So I pinched a bike box from the shop because they're double-thickness corrugated cardboard, and set to with knife and PVA and little reinforcing sticks of willow and when it was all done, I carefully covered it inside and out with cut-up cotton shirts ostensibly to reinforce it but actually cos I fancied the idea and wanted to see if it would work.

 
Messrs McLeod and Schroder appeared and we went for a ride, Mr McLeod with his new tail fairing which was thin and flimsy and lightweight and insubstantial and rubbish all of which compelled me to assure him it wouldn't work, but in the event I was wrong. It worked exceedingly well. A roll-down at Ngatimoti said 38.8 kph without the fairing and 40.6 with, and whenever I followed him I found that I wasn't picking up a tow but was riding into immense turbulence which entirely validated his roll-down data. The tailbox was a single fold of corriboard, neatly sealed at the front with foam, and held in place with tiny light-weight rubberised cotton bands weighing nothing. Admittedly his drive chain was creating a series of hiccups, but nobody's interested in drive trains. They're only the means of testing the aerodynamics of single folds of corriboard. (And on the topic of hiccups the children who have decided I am to be knighted, presumably for services as yet unrendered, observed that the worst time to get hiccups is when the Queen is about to knight you. It is a prospect that doesn't fill me with alarm because I'm neither a rugby player nor a film producer and Her Majesty is not yet in the habit of knighting cardboard box makers.)


Mr Schroder had his fork jig with him which I shall probably have to nick sometime, and he tried to persuade me to ride from Rotoiti to Renwick with him but I declined because I'm pathetic and a wimp and it's a long way and he's too fast. Mr McLeod will have to go instead.
 
 
In the morning I nipped up Mount Arthur to see how they were all getting on and was much cheered to find that Dr Dane-Mollerup is another person who shaves his own head, doubtless to save having to discuss whatever in Denmark constitutes Leicester City with whoever in Denmark cuts hair. - By way of instigating stimulating conversation the barber in Barrow used to ask of each client:
'Y'suppor' Leicester City, er wha?'
Naturally I did not support Leicester City nor indeed any other team but I did not disclose this to the man because he had sharp implements and my throat to hand. Instead I bought a BaByliss and proceeded to shave my head with a Number 4, deeming that however ragged a mess I made in the mirror it would be preferable to a bimonthly discourse on association football. If you see a man with hair exactly half an inch long you'll know he has a BaByliss, and if there's a diagonal intrusive pathway mown out of the back of his neck only an eighth of an inch long, you'll know his wife declines to shave the last few bits for him with a Number 1.

Up the mountain was a Troll. He had appeared long after dark outside the hut, hopping about with a torch on his forehead and waking everyone up shuffling through his pack, and in the morning he set about advising people what not to do. Not to wear cotton shirts, not to wear cotton jeans, to choose different boots from the ones they had and to go on routes other than those they proposed. In short, to do what he was doing. Everyone ignored the Troll so he had to accompany them all day to give further advice, suddenly rushing ahead with his mountain sticks, randomly announcing which of the range is named Gordon's Pyramid and which Billy's Knob, and surprising people who hadn't ever seen him in their lives before by gratuitously pointing out the route to Salisbury Hut. He was most odd. He was covered in tattoos, very probably inflicted by mountaineers who had tired of his advice. I have a feeling he lives on the mountain, so when I next go up there I'm taking my cardboard box and I'm going to spend quality time advising him how to make one using inappropriate materials like cotton and we'll see who can be the most annoying and I bet it'll be me.





Schroder's Hat 

The bin man calls here of a Monday morning, and from this statement I divine a Great Insight: that I am the vainest person in the world. Paris Hilton thinks America wants to spend its broadband connection examining her limbs and all that pertain thereto; Alan Jones believes Australia wants to listen to his radio show encouraging motorists to run cyclists off the roads; but only I am vain enough to think that the entire Internet wants to know when the dustman empties our bin.
 
Waste disposal in New Zealand is a private affair: you have to pay for it. Accordingly most people gather their domestic rubbish and lob it out of the car window. (Next time there's a world shortage of used empty paper tubs for Kentucky Fried Chicken, I'll make a fortune just cycling along the Motueka Valley Highway and stopping every ten yards.) The bin man empties an old oil drum for $10.30 - the price occasionally increases to randomly inconvenient sums that aren't to be found in a wallet of a Monday morning - and to get our money's worth there's always a scurrying around at the dawn of the week for stuff to chuck out. Yesterday I remembered a pair of forks which came my way. (Build just one recumbent - one - and people will start to give you old bike bits. I guarantee it.) And I now offer this piece of Wisdom to the World: Unless you are completely stupid, little is to be gained by welding this onto a pair of front forks:
 

Had I possessed a munted helmet that too could have gone in the bin. Scrolling to the bottom of this discussion
http://www.kiwihpv.org.nz/phpBB3/viewtopic.php?f=8&t=36&start=20
I see there's a photo demonstrating the force of impact of Nigel Schroder's skull on those boulders the other day. (One's concern is, of course, for the rocks. Schroder's a solid beefy sort of lad and if he hadn't had the hat on, I dread to think what might have happened to those boulders.)
Wednesday, August 4, 2010 3:59:59 AM Categories: bike crash injury Nigel Schroder Roll-down tests

Schroder's Cat 

 
Here, for no very good reason that I can think of, is a picture of the Maruia Falls. I had to steal this from harlequin.co.nz because the one I took got lost somewhere in the dusty innards of my computer. The Maruia Falls are très pretty but that isn't why we send all our visitors there. It's because in 1928 they weren't. In 1928 they were just a plain common-or-garden scenic river. Still Glides the Stream and Shall Forever Glide (1), until the 17th June 1929 that is, when, after a few days of the locals hearing what they thought were aberrant deer stalkers in the hills, there was a mighty cataclysm and the Mairua River suddenly broke in half and dropped  nine feet ten-and-a-ninth inches. (That would be three metres, Mr Hague, though frankly I feel your espousal of these narsty - ew - French measurements borders on the philistine.) This is an altogether more satisfying earthquake than the ones where a picture goes slightly askew in a housing estate on the outskirts of Peterborough, even if a clutch of people have to get buried in landslides for it to happen. We haven't had an earthquake for a while and therefore I suppose we ought to expect one. Pleasingly the estate agents have all bought houses for themselves on the Richmond Hills which command a view over Nelson bay, not thinking about the fact that the Richmond Hills only exist because occasionally they shoot upwards three metres at a time.
 
Below the Richmond Hills are the Saxton Playing Fields crammed of a Saturday morning with all the Nelson schools' sports clubs, and it falling to my duty to endure a van-load of the truly mindless conversation of my daughter's hockey team, I thought I would skip spectating for an hour and drop in unannounced on James or Nigel or Sam, who all live conveniently nearby waiting, no doubt, for a hearty terrestrial shaking to land a selection of startled estate agents in their midst.
 
To James McLeod's. James's neighbour was washing his car and had mistakenly thought the entire neighbourhood wanted to hear his choice of what purports to be Music but in fact James, unable to bear the din, had gone out. James is of Scottish descent and, I hope, about to take up the bagpipes by way of retribution.
 
To Sam McEachern's. There stood his blue recumbent on the verandah with its new seat upholstery but there was no sign of Sam nor indeed of any of his neighbours, so perhaps he had spent the morning giving James some preparatory bagpipe lessons.
 
To Nigel Schroder's. No neighbour, no Music, but no Nigel either. And there stood Nigel's new low racer, gleaming in his shed, so obv. they weren't all off secretly riding up the Richmond Hills together.
 
Nigel's new machine is a front wheel drive with a swinging bottom bracket. I knew he'd finished it because he sent me film http://www.youtube.com/watch?v=FG5okNSvpTY of him riding it and he seems to be more in control of it that I ever was of the one I made, which after it whacked me in the side of the head got punished with a hacksaw.
 
However in the evening I had a doleful email:
 
Well the roll down - at Marsden Valley, the same place we did the last test - didn't quite go as well as planned. The old bike had topped out at 55kph and on the first run the new bike was faster at 58kph but I had to use the brakes a little to regain control as it started to wobble .
On the second run things went a little wrong. I crashed at about 50-55kph.
Fell from the bike and slid down the road a little then into a creek hitting some very large rocks on the way. My helmet was completely destroyed. James drove me home, then we went to the hospital where I spent the next 7 hours being checked. X-rays and a CT scan. Luckily nothing was broken. Feeling very sorry for myself today. As for the bike it's ok but it's the last time I'll ride it as a moving bottom bracket, so I think it'll get a rebuild and I'll go back to having a boom and a twist chain FWD. The moving bottom bracket was just too unpredictable. The speedo had a 55kph max after the crash and I hadn't got to the fastest section of the run.
Nigel
 
My daughter Susan gaily said 'If he keeps the broken bits he can call it Schroder's Cat, cos it can be a crashed and an uncrashed bike at the same time,' which stunningly obscure joke can only be understood by quantum physicists one of whom I am not.
 
Anyway as - surprisingly - there was no gravel rash we can't twin him with Bob Knight, and as there were no broken bones we can't twin him with Geoff Bird. But there were bruises everywhere and he's very sore so we can twin him with oh, just about everybody else in the recumbent-building fraternity, I should imagine.
 
1. Wordsworth who is famous, or Arthur Streeton who ought to be famouser.
Monday, July 26, 2010 9:27:17 AM Categories: injury Moving Bottom Bracket bikes New Zealand Nigel Schroder Roll-down tests

Foam roll-downs. (Or rolls-down if you prefer.) 


Anxious to Compare and Contrast, I took the newly built, but not yet photographed (a mistake as will be seen) fairing to a certain hill I know and love, and did roll-down tests before the forecast rain that didn't happen. (The above is of the tailbox only, which information I include for those who imagine I pedal backwards. My tailboxes have been huge ever since a conversation with John Lafford, who (I'm summarising) said 'Make your tailboxes huge'.)

Tailbox only:
25.2 mph
25.1
25.3

Blue front fairing plus tailbox:
26.6
27.2
27.2

Blue front fairing only:
26.5
then I got my cleat stuck while stationary and fell over and snapped most of the wooden slats inside the fairing and cut the top off my little finger on an errant bit of sharp road
26.4
26.3

No fairings whatever:
25.6
25.3 with my RH on the handlebar extension but my LH over my chest
26.0 with my RH on the inner part of the handlebar and my RH over my chest

all of which took exactly one hour.

Then a strange man came wandering over from the adjacent field, stubbly (the man, not the field) and dribbling a little, with an elderly shotgun lodged in the crook of his arm. Whereupon I felt I ought to speak to him to explain what was going on.

I said 'I'm just testing different fairings on a recumbent bike because when each is changed, the hill gives me clear results' and the stubbly man said 'Clear results, that's right' dribbling a bit from the corner of his mouth. I said 'I roll down the hill to see how fast I get up to on my computer.' The man said 'My computer, that's right, mm,' and I thought this is strange, he is unable to compose and speak a sentence; all he can do is repeat the last two words I've said. And then I started to think that this is going to be either the most interesting or the most uninteresting conversation I've ever had in my whole life so just to see which, I continued: 'First I put the tail fairing on and roll with that, and then I add the front fairing, and then I see what difference it makes.' 'Difference it makes,' said Stubbly, dribble dribble. At this point I wanted to hug him for having survived for so long despite being completely and wholly stupid but then I began to think of those horror movies that used to come on Channel 4 on a Thursday night where a Perfectly Innocent American Person goes into the woods and meets a Strange American Person Who Already Lives There and all sorts of unpleasantnesses that I'd rather not remember ensue. So I hurriedly set off in a southerly direction and was swiftly followed by a volley of shots.

(Okay. Maybe some of this is untrue. Maybe I just wanted to add a bit of colour to an otherwise bland account. )

So we can conclude that my fairings are rubbish, if we are to be honest and objective. And I wonder if this is partly because of the large hole - well, the non-floor - which creates colossal drag. Neglecting the hideous knobbly shape. Pictures will have to follow when - if - it ever gets repaired. Anyway this provoked the following angst-ridden exchange:

Uh? It seems that the tail fairing on its own makes no difference, indeed possibly a minor decrease in speed. The front fairing does make an improvement. The front fairing + tailbox is even better. Do you concur? I'm impressed that you can take a hand off whilst riding. There is no way I can do that on the ratracer. It is *pissing* down here at the moment and I am sat sitting here on my stool in a medium sized puddle having got thoroughly drenched on the way to work 'smorning. I've just read the paper and it gleefully reports a big depression that will cause a lot of weather later this week and at the weekend. At least I'll be able to get some planking done on the fairing. Incidentally I threw a sheet over the frame last night to get an idea of the shape and I was surprised how large it is. It is 20" wide at the widest point and this looks enormous. - Bob

Whenever I've made fairings, front and rear, 's orlways been the same. The tail adds *at best* half a mile an hour, the front adds about a mile an hour, and both together add a further half mph. But my level-ground racing speed is too slow for the tailbox to collect separated flow and reattach it. My brother tells me that his recumbent motorbike tailbox is very significant. Mind he does have a very good front fairing too. Implication of Hucho (p311) is you need a big rear section and a fairly high Reynolds number before air re-attaches once it's separated. I forget what my Reynolds number is - I worked it out once - but it was significantly less than the lorries Hucho was describing.
The present tailbox in earlier roll-down tests gave me an extra 0.36 mph at 23/24 mph. This is a whisker less than I had expected, but even so I was surprised by the result showing a reduction in speed with the tailbox. To be statistically valid, I need a *lot* more trials but they take a huge amount of time to do, and as the morning wears on the wind gets up so you have to stop. One problem is that I notice myself tensing, even during a roll-down, and when I relax I go faster. This *might* be because I flop lower down in the seat when relaxed, but there may be other reasons that I haven't figured out yet. I do know the gain is small, and it's also highly variable between runs.
In Engerland, fair Engerland, there was a hill outside Barrow on Soar which after a gentle slope getting me to 20 mph and holding it there for a good steady 200 yards where I could read off my (realistic) road speed, then dropped away to a valley floor where I hit 30mph before slowing up on the other side of the valley. The impact of tail fairings was much bigger at the higher speed.
Example: Paudy crossroads to Walton, 13.12.97.
MWB touring machine with large foam tailbox: 21.5 mph, max at bottom of hill 30 mph
Same with tailbox removed: 21 mph, max at bottom of hill 28.5 mph. - R

 

Wednesday, May 20, 2009 8:47:00 AM Categories: Foam fairing Roll-down tests
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