Yet Another Cycling Forum

General Category => Freewheeling => The Dark Side => Topic started by: Mr Larrington on September 06, 2015, 04:15:10 am

Title: Battle Mountain 2015
Post by: Mr Larrington on September 06, 2015, 04:15:10 am
The annual Hurtling Contest in the deserts of That Nevada doesn't get underway in earnest until the 14th inst but rest assured that your faithful reporter will be, er, reporting again.  More Stuffs at the Automatic Diary (http://automatic-diary.blogspot.co.uk/).  Event webby SCIENCE is at http://www.recumbents.com/wisil/whpsc2015/speedchallenge.htm (http://www.recumbents.com/wisil/whpsc2015/speedchallenge.htm).  Time for Tea.
Title: Re: Battle Mountain 2015
Post by: Auntie Helen on September 06, 2015, 05:59:25 am
Looking forward to reading all about it!
Title: Re: Battle Mountain 2015
Post by: yanto on September 07, 2015, 11:08:54 am
just joined the automatic diary, nothing like reading it as it is*

* lie

Ian
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 13, 2015, 12:36:38 am
Arrived in BM about 90 minutes ago.  Aerovelo (Toronto) and Policumbent (Turin) are here at the Super 8, as are the mid-west mob - there's a fairly old-skool looking machine with a pink frame insode the fairing which I suspect is the Mini-Moby being raced by the Kowalik girls in the junior category.  No sign of the Scousers but they could well be at a different motel.  Hopefully some pictures will be forthcoming later: they'll be at https://www.flickr.com/photos/mr_larrington/sets/ (https://www.flickr.com/photos/mr_larrington/sets/) in albums labelled "BM2015 - $day_of_week"  At least the network here is working, unlike last night chiz >:(
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 13, 2015, 05:36:51 pm
Just heard that the trailer carrying the new bike from Eric Ware & Mark Anderson for local lass Teagan Patterson to ride is stuck in Salt Lake City after villains robbed the trailer.

Team Eivie have just appeared, having got in at 2 am.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 13, 2015, 09:10:27 pm
More people are arriving, though apparently Them Russians won't be here until the latter part of the week.  I have been volunteered to help out with scrutineering this afternoon but in the meantime there are some more photos here: clicky (https://www.flickr.com/photos/mr_larrington/sets/72157658486151006).

Not seen the Plymouth handcycle, Velox 5 or the Scousers' bike yet coz they're staying elsewhere but hopefully will snap some pics later.  If the flatteries in my camera hold out.  I only put new ones in on Monday.  And if I want Energiser lithiums or the local equivalent I'll probably have to go to Elko to get them.  140 mile round trip :(
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 14, 2015, 07:33:21 am
Just about everyone is here now and the good news is that the rozzers have recovered the stolen bits of Teagan's machine, which just leaves the small matter of someone making the 600-mile round trip to fetch them tomorrow.  Since it is late and I have to be up at audax o'clock in the morning, Sunday's Automatic Diary update has been delayed until after the morning qualifying runs.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 14, 2015, 10:47:44 pm
Back from:
Conditions not brilliant but Liz McTernan's 24.72 mph run on her unfaired Top End handcycle "Red Lightning" constitutes a new world record for BRITAIN, Florian Kowalik's 53.41 in the CO2 is a Junior Multitrack record and Todd Reichert did a 72 mph run with a 2.5 mile run-up, which is the fastest yet seen over the short course, though I don't know whether the wind was below the permitted maximum for that one.

There are a swarm of people clustered around a big pile of Stuffs just outside my window putting Teagan's bike together :thumbsup:  However Natasha Morrison won't be running in the Liverpool bike as she wasn't able to get the thing to stay upright when starting off.  Good runs for Ken Buckley and Dave Collins though.

Most people got down the course OK except the Delft/Amsterdam machine Velox V which had two launch fails for Lieske Yntema and one got-going-OK-but-then-fell-over for Robert Braam, who is a late substitute for the injured Rik Houwers.

Photos from Monday at https://www.flickr.com/photos/mr_larrington/albums/72157658637494215 (https://www.flickr.com/photos/mr_larrington/albums/72157658637494215)

Weather forecast for the week varies according to who you ask/believe but the consensus is for rain either Tuesday or Wednesday.  We did have a few spots this morning but not enough to affect anything, and it was about fifteen deg. C warmer than the usual single-digit morning temperatures today.
Title: Re: Battle Mountain 2015
Post by: Peter on September 15, 2015, 01:16:14 am
More likely they forgot to put the pilot in!
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 15, 2015, 03:29:00 am
Not sure what the problem was for Velox V this morning; I believe their riders had a fair amount of practice in .nl before coming here.  Bluenose's chainguard self-destructed and the addition of stretchy latex around the front wheel opening of the Micro-Moby caused the steering to pull sharply to one side; advised to steer the other way Genevieve Kowalik ignored the sage advice of her father in the manner of ten year olds everywhere, and fell over.  Jan-Marcel van Dijken dropped a chain and couldn't get it back on this time so coasted through.  Full Monday morning results and some nice pictures from the timing area on Jun Nogami's blog (https://jnyyz.wordpress.com/2015/09/14/bm2015-monday-morning-runs/).

The gloomy prognostications regarding the weather have proved all too accurate and there were no runs on Monday evening as no-one can ride a streamliner through a gale-impelled sandstorm.  Forecast for tomorrow morning looks a bit lot rubbish too but we'll cross that bridge when we "accidentally" forget to set the alarm clock for five am.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 15, 2015, 09:42:27 pm
Although Velox V was pronounce fit and healthy last night the team didn't show this morning for qualifying ???  A bit too breezy for most people's runs, on both the short and long courses, but Ellen van Vugt bagged a women's multi-track world mark with a legal 51.92 in Garrie Hill's machine CO2 (a replica of the former trike world record holder Completely Overzealous).  Apropos noxious gases, Todd Reichert has a CO2 meter inside Eta.  I don't know whether it helped but he became the fourth person to exceed 80 mph here, albeit with a breeze coming from his left stern quarter.

Jan-Marcel dropped his chain (the left side final drive one this time) in his qualifying run but still did almost 58.  Some filing and graunching ensued and he then did a 76 over the full course.  This is pleasing, as I am a semi-official part-time member of Team Cygnus this year.  As long as they pay me with stroopwaffels.

Dave Collins also dropped a chain in ARION1 and coasted in for 39.5 mph, allowing Larry Lem to get in too close for the latter to be given a speed, but They reckon about 66 mph.  Liz McTernan ran unfaired over the full course and did 28.84 mph, but the wind was too high for this to be a new record.

They're showing off the machines to the Tinies at the moment, which makes my feet hurt, so I grabbed the free lunch, took some photos, grabbed another free lunch and came back to the motel to upload the next tranche of pictures.  Look for "BM2015 - Tuesday" at https://www.flickr.com/photos/mr_larrington/sets/ (https://www.flickr.com/photos/mr_larrington/sets/) as they're still at it.

Blowing a bit and only 20 degrees but there's still a couple of hours before the evening sessions even start getting set up.

ETA: Evening session rained off.  Piss.

ETA: This is what Tuesday evening looked like from timing:

(https://jnyyz.files.wordpress.com/2015/09/storm-bm-bw-s.jpg)
Pic by Danny Guthrie

Monday evening looked even worse.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 16, 2015, 01:58:22 pm
It is raining.  It has been raining all night.  No runs Wednesday morning.  Piss.

Also I spelt Erika's name wrong.  Sorry.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 16, 2015, 06:28:06 pm
Sun came out not long after it was supposed to have risen and apparently the rider/machine combinations who were yet to qualify went out and ran.  There is a meeting in half an hour or so; if anything exciting transpires (Ha!) I will post an update.  Or let Jun do it :)
Title: Re: Battle Mountain 2015
Post by: ElyDave on September 16, 2015, 09:09:54 pm
some very interesting pics of some very interesting machines, thanks for keeping up with this.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 16, 2015, 09:54:47 pm
Robert and Lieske both qualified successfully, as did Calvin Moes in Bluenose.  Sherry Shi decked Bluenose at the start and didn't get a run in.  Apparently both the timing area and the spot we use for the short course start were akin to Glastonbury in a bad year.  Meanwhile, here is a pciture of a wol:

(https://farm1.staticflickr.com/645/21286342580_40542e0279_c.jpg) (https://flic.kr/p/yr153y)
P9160563 (https://flic.kr/p/yr153y) by Mr Larrington (https://www.flickr.com/photos/mr_larrington/), on Flickr

Sunny but not very warm ATM  Fingers crossed for an evening of any runs at all.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 17, 2015, 06:16:06 am
None too warm this evening but the wind was better than expected.  Todd Reichert nevertheless decided not to run and may well be kicking himself now.  The teams asked us to push back the runs as late as possible which proved to be something of a curate's egg.  We ran three heats and none of the four riders in the last heat had a legal wind speed, which is the opposite of what usually happens.  Things didn't go brilliantly for the Liverpool team; Dave Collins had a skipping chain and got 60.57 mph while Ken Buckley had camera issues and trundled through at 31.64 with Lieske Yntema in Velox V close behind.  This made life in catch somewhat interesting, but both teams have a plentiful supply of Penniless Student Oaves so no-one had to ride back to town in the dark.  Top speed of the night was my man Jan-Marcel van Dijken in Cygnus Chronos, with a fully-legal 75.31, which means he won't go out tomorrow morning, which in turn means I can do other Stuffs.

Pictures from this evening at https://www.flickr.com/photos/mr_larrington/albums/72157658293144988 (https://www.flickr.com/photos/mr_larrington/albums/72157658293144988) once they've finished uploading; full results will be on Jun Nogami's blog at https://jnyyz.wordpress.com/ (https://jnyyz.wordpress.com/) once he's had his dinner.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 17, 2015, 09:47:51 pm
Just back from very late breakfast, or possibly lunch, following the morning runs.  First the good news:

New BRITISH record for Ken Buckley in the Liverpool University machine ARION1.  69.73 mph, so ~2 mph faster than Rob English's previous mark set in 2002.  Hurrah!  Hurrah for BRITAIN!

After a bunch of very late nights Mark Anderson and Steve Nash have got the Seiran up and running.  Teagan Patterson did a couple of practice starts in the Civic Center and then qualified the bike at 56.50 mph on the short 2.5 mile course.  No problems reported and IIRC she'll be running it over the full course this evening.

Just one more thing, as that scruffy bugger in the raincoat used to say.  Todd Reichert had legal wind and clocked 85.71 mph for a new world record in the Aerovelo Eta.  I was at catch so don't have any pictures of the bike at full chat but I dare say there'll be plenty in Intertube-land.  Muted BRITISH-stylee congratulations to Canada and all who sail in her :D

Edit:  Blast, scooped by Oranj!  I had to buy some more fags on the way back from the diner chiz.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 18, 2015, 05:49:50 am
Sadly Ken decked the AR1 at about 55 mph this evening while about two miles from timing.  He's OK; I haven't seen the bike but it doesn't sound pretty :'(  Conspiracy theorists say it's to ensure Dave can't have a crack at the BRITISH record.  Ellen upped her women's multitrack record to 54.45 mph, Todd did 82.29.  Which would have had us pretty excited this time yesterday.  Damjan's 79.16 is, we think, his personal best with legal wind.  Teagan's 58.94 was also legal and if they can actually get some kind of computer on the bike...

Things didn't go so well for Team Cygnus; Jan-Marcel had an off day and decked three or four times (I couldn't quite see as the start officials' car was in the way) before overrunning his two minute start slot.  We won't be running tomorrow morning but hopefully the machine will be reasonably reshinificated for the evening.

Todd's having the morning off as well.
Title: Re: Battle Mountain 2015
Post by: spesh on September 18, 2015, 08:35:45 pm
http://gizmodo.com/this-bike-is-the-fastest-human-powered-vehicle-in-the-w-1731643276

Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 18, 2015, 08:56:57 pm
Just back in from the morning's happenings.  Much midnight oil was burned by the Scousers and the AR1 was back out on the course with both Dave and Ken getting down the road OK.  Dave did a 62; Ken ran later when the wind was starting to pick up and caution kept him down to 40 or so.

Not been a brilliant week for most of the PSO teams; the luckless Sherry Shi decked Bluenose yet again though at least she's crashing nearer to timing each morning.  Robert Braam binned Velox V about 600 metres from the traps.  Bikes and riders generally OK though there will be a good deal of filling and sanding going on this afternoon.

The shining exception to the above are the Italians whose four-man operation is as slick as any bunch of grizzled veterans.  They turn up on time, get Andrea into the bike and off down the road with the minimum of fuss and collect him in once piece at the other end.  The PulsaR is still as shiny as it was on Sunday.

Weather appears to be almost back to normal today with 4 degree showing on the motor-car at catch.  Cloudless skies and warming up nicely.  Todd is down for the first run this evening...

Dr No1 would appear to be having his lunch but the morning results should be up on https://jnyyz.wordpress.com/ (https://jnyyz.wordpress.com/) soon.  My Friday photos, such as they are, are at https://www.flickr.com/photos/mr_larrington/sets/72157658371242359 (https://www.flickr.com/photos/mr_larrington/sets/72157658371242359)

1: Jun did a legal 49.52 this morning but has given priority to Florian to run the CO2 tomorrow.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 18, 2015, 09:00:24 pm
http://gizmodo.com/this-bike-is-the-fastest-human-powered-vehicle-in-the-w-1731643276

See also http://www.gizmag.com/cyclist-human-powered-speed-record/39472/ (http://www.gizmag.com/cyclist-human-powered-speed-record/39472/).  Pity they can't spell Todd's surname.  Or Sebastiaan's, come to that.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 19, 2015, 06:29:27 am
Much warmer this evening and the wind was friendly enough that everyone who completed the course did so with a legal wind speed.  Dave made a solid run in AR1 but Ken went on the side of caution and pulled up mid-course - a flawless catch by the crew.  They are celebrating by heading back out into the desert to nick the wheels off Mark Mueller's MX51 which, after a bit of over-enthusiastic dirt-road hooning, is in a ditch with two fewer working tyres than it had this morning.

Communications problems meant the third of the evening heats was later than we'd hoped so neither Damjan nor Jan-Marcel got their hoped-for 80 mph hats; Ellen had a good run with a 69.  Earlier Andrea went over 70 to increase his Italian record and, chiz curses, put it higher than Ken's BRITISH one from earlier in the week.

First run of all tonight was that pesky Reichert fellow, who only went and banged the world record out to a scarcely believable 86.50 mph, or 139.18 km/h if you prefer.  The bike has a design speed of 140 km/h, there's still one evening to go and the weather forecast for tomorrow is for even better weather.

1: Lie.
Title: Re: Battle Mountain 2015
Post by: Torslanda on September 19, 2015, 10:15:34 am
Think he's a bit busy driving Micras or something . . .
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 19, 2015, 10:35:20 pm
The rules require complete redundancy for camera bikes - camera, screen & wiring.  Although if the rear wheel rubs right through all the anbaric string...

Seems the Velox V was more badly banged up than they thought in Robert's crash as when they tried to run this morning the front of the fairing wouldn't go on.  They're not going to run again.  Too windy for much to happen this morning though Genna Kowalik did a 40+ with non-legal wind and a legal 37 on her second go, so a new record for her age group.  She's ten.

There'll be the group photos up on Flickr soonish, not to mention Officer Aten handcuffing Todd and chucking him the back of the cruiser.  One more set of runs to go and it's already warmer than it was yesterday evening.  Fingers crossed for the weather.
Title: Re: Battle Mountain 2015
Post by: ElyDave on September 19, 2015, 10:59:12 pm
Just back from very late breakfast, or possibly lunch, following the morning runs.  First the good news:

New BRITISH record for Ken Buckley in the Liverpool University machine ARION1.  69.73 mph, so ~2 mph faster than Rob English's previous mark set in 2002.  Hurrah!  Hurrah for BRITAIN!

After a bunch of very late nights Mark Anderson and Steve Nash have got the Seiran up and running.  Teagan Patterson did a couple of practice starts in the Civic Center and then qualified the bike at 56.50 mph on the short 2.5 mile course.  No problems reported and IIRC she'll be running it over the full course this evening.

Just one more thing, as that scruffy bugger in the raincoat used to say.  Todd Reichert had legal wind and clocked 85.71 mph for a new world record in the Aerovelo Eta.  I was at catch so don't have any pictures of the bike at full chat but I dare say there'll be plenty in Intertube-land.  Muted BRITISH-stylee congratulations to Canada and all who sail in her :D

Edit:  Blast, scooped by Oranj!  I had to buy some more fags on the way back from the diner chiz.

I've been to Canadia a few times, to be honest it's more like GB than Liverpool is.   Asked for HP sauce for my chips, appeared out of nowhere with no fuss whatsoever.  I think we could claim any of their records for the old country.

Ask the same question in Houston...
Title: Re: Battle Mountain 2015
Post by: Von Broad on September 19, 2015, 11:08:33 pm
sorry, but naive question...

what's the deal about camera bikes as opposed to bikes that have a viewable window?
Is it...that it's just easier to build a faring where you don't have too worry about fabricating a see-through window that is also cleaning aerodynamic?

86.50mph...wow, that's now nearer 90mph than it is 80mph  :)
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 19, 2015, 11:45:30 pm
Cameras do make it easier to get a nice clean shape as the rider can be leaned further back.  Jan-Marcel says that in his riding position he'd only be able to see his knees.  As a bonus, the electronics enhance the view in low light such as we get when the evening sessions are running late.  Reliability and resolution are now both very good and if you're suitably clever you can overlay all sorts of information onto the basic view rather than just scrawling a list of target speeds on the inside of the windscreen with a crayon.  Todd is even monitoring CO2 levels :o
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 20, 2015, 08:26:05 am
Just back in from the final evening runs and the awards bash.  Todd edged his world record out to 86.65 mph and Damjan finally got his 80 mph hat with an 80.01.  And then crashed Eivie 4.2 in what was apparently a deeply spectacular way.  He's OK but the bike is almost certainly a write-off.

Dave in the AR1 set a new BRITISH record with a 70.60, but it didn't last long before Ken trounced him with a 75.04.  Which puts BRITAIN ahead of Italy - since Andrea only managed a 72.19 tonight - and Australia (not playing this year).  Some of the Scousers would have been bouncing off the walls while still out in the desert if there were any but Dave and Ken both just told me they're too knackered to party any more.  Top work by the whole team to get the bike back together and running with the big boys.

My grate frend Jan-Marcel only managed a 76.49 tonight (cramp with two miles still to go) but still bagged third overall behind Todd and Damjan.  Erika says this is his fifth third in six years :-\

No photos from this evening uploaded yet coz I'm going to bed.
Title: Re: Battle Mountain 2015
Post by: ElyDave on September 20, 2015, 08:56:35 pm
Some very fast times indeed, how long before they're closer to 100 than they are to 90?
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 21, 2015, 01:50:11 am
A minor correction, if I may be so bold; the Varna shape was subject to no computer refinement whatsoever.  Georgi Georgiev shaped them entirely by eye (he trained as a sculptor) and when the riders complained that they were too small he made them smaller ;D  Though something didn't go quite right with the Varna Battle Mountain as Barbara was always quicker in the slightly larger Tempest.  Also this year Aerovelo concentrated solely on Todd; Trefor Evans and Calvin Moes both rode it last year and while they're both quick they're not in the same league as Todd.

The Liverpool bike is a good deal bigger than Eta, albeit that Ken is also a good deal taller than Todd.  The Italian bike PulsaR is frikkin' huge by comparision.  Once the photos have finally gone up you'll be able to see what a tiny chap Andrea is...
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 21, 2015, 05:08:37 am
A minor correction, if I may be so bold; the Varna shape was subject to no computer refinement whatsoever.  Georgi Georgiev shaped them entirely by eye (he trained as a sculptor) and when the riders complained that they were too small he made them smaller ;D  Though something didn't go quite right with the Varna Battle Mountain as Barbara was always quicker in the slightly larger Tempest.  Also this year Aerovelo concentrated solely on Todd; Trefor Evans and Calvin Moes both rode it last year and while they're both quick they're not in the same league as Todd.

The Liverpool bike is a good deal bigger than Eta, albeit that Ken is also a good deal taller than Todd.  The Italian bike PulsaR is frikkin' huge by comparision.  Once the photos have finally gone up you'll be able to see what a tiny chap Andrea is...

Edit: did you ever see such a sorry-looking bunch of crims in your life?

(https://farm6.staticflickr.com/5751/20962006933_4b9e44a989_c.jpg) (https://flic.kr/p/xWkLmD)
He's a villain, sir! (https://flic.kr/p/xWkLmD) by Mr Larrington (https://www.flickr.com/photos/mr_larrington/), on Flickr

The ne'er-do-wells ticketed for exceeding the posted speed limit on Highway 305, for deviating from their travel lane1 or, in a few select cases, both.  L-R: Sergeant Arthur Aten of the Highway Patrol, Todd Reichert, Jan-Marcel van Dijken, Andrea Gallo, Damjan Zabovnik, Ken Buckley, Sherry Shi, Robert Braam, Lieske Yntema, Dave Collins.  Note extreme titchiness of Andrea (Jan-Marcel is about 6'3" long).

Clicky me for further Saturday pictures (https://www.flickr.com/photos/mr_larrington/albums/72157656502428574/with/20962006933/)

1: i.e. crashing (falling over at the start doesn't count)
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 24, 2015, 05:06:52 am
At the moment, I'd guess that Todd is putting out 450-500W for the last 30 seconds of his run - and timing that sprint correctly too - from a slow build at 250W. For a rider in the recumbent position, this is seriously world class. If Todd wanted to break 100mph, he'd need 750W for a significant length of time (i.e. longer than 5 secs). It doesn't look very likely: 150% of Saturday's performance.

The Scousers have put up the raw SRM data for Dave Collins' Saturday morning run: clicky (http://s000.tinyupload.com/index.php?file_id=94347156468750075725).

The pretty output looks like this:

(http://s13.postimg.org/7ekksbt8n/test1.png)

although the writing is probably too small to be of much use.
Title: Re: Battle Mountain 2015
Post by: Clare on September 24, 2015, 09:41:34 pm
Mr Larrington, once again you have provided excellent reportage and given me a good few laughs  - thank you.

Title: Re: Battle Mountain 2015
Post by: Mr Larrington on September 25, 2015, 12:35:03 am
Thanks, I've picked that up. It's a shame that it's only Dave's 60mph Saturday morning run, but it presents some useful data.

I had a root around trying to find some decent local weather info, and it looks like the mornings in Nevada are bad for high speed racing (at least, that particular Saturday was), with cold, thick air - an air density of 1.2653 kg/m3 (typical UK conditions yield 1.21, and shortly before a thunderstorm broke over the Shaftesbury 50 a couple of years ago, I rode in air density of 1.16, the lowest I've ever measured/calculated (a 50-mile PB resulted  :) )). I also got the grade of the course from the recumbents forum (~0.5% at the traps).

Anyway, a nice build through 250-300W sees Dave get up to speed pretty quickly and then he clearly goes for it at the 6km mark, with an average 387W for the last minute and a 5-second peak around 424W just as he enters the traps.

Despite this, it's hard to gauge how aero their bike is - I'm having to make guesses about how much it weighs with a rider in it (I've had to make it 100kg to fit the speed/power), how lossy the crossover drive is (4%? an average TT bike is around 3%) and the fact that for this run they note they were using slower, more stable tyres (so a crr of 0.004, say, rather than 0.003 for nice radials - my best TT tyres are around 0.0035-0.004 too). Anyway, plugging all those numbers in gives a CdA of 0.029, which doesn't seem that amazing - maybe that camera bike estimate I got upthread was off the mark.

The Battle Mountain evenings are supposedly much better for speed: on that Saturday evening the air density dropped to 1.2085 kg/m3, which is a huge variation from the morning. Given the same ~400W output, Dave would go only 2mph faster in the evening, according to the calculations I'm using. I think that shows that for a slippery bike like this, air density is a factor, but nowhere near as much as it is for a draggy object like, say Bradley Wiggins on a track bike. This also explains how Todd was able to go so fast on his first record-breaking run, in the morning, and then only be able to add another mph in two subsequent evenings. I wasn't expecting that. Dave and Ken must've had a strong coffee or two before their evening 70 and 75mph runs (and I know from experience that most of us breathe more easily/put out more watts in warmer air).

[EDIT: in the same bike, Todd would need ~1000W to go 139km/h, but if Eta is only CdA 0.02, then a more believable 639W, that's still quite a lot, so maybe it's slipperier than that, or the online calculator I'm using is off.]

Elsewhere Damjan Zabovnik has posted that "CdA of Eivie IV is 0.0083m2.  I measure deceleration when I stop pedalling, taking into account Crr, air temperature, slope, mass. CdA can be extracted that way."  Mind you, that thing is tiny.
Title: Re: Battle Mountain 2015
Post by: Mr Larrington on January 27, 2016, 12:03:10 pm
It's just been pointed out elsewhere that claims on the BRITISH record by Messrs Buckley and Collins may be a bit previous chiz as Trefor Evans did 76.84 mph in Bluenose in 2013 and he has dual BRITISH/Canuckistani nationality.