Time Trial / Time Trialling / TT

Just seen this - Woodburn cheated. There is a photo of him pulling Stan along on the album posted on the ctt website.

One picture isn't proof of cheating - the Gentleman is permitted (indeed, expected) to lead over the line, and the rule about when he can go to the front varies, from the last mile to just the last 100 yards. If the photographer was near the finish, you would expect John to be on the front.

Mick Bradshaw, from the olden days (i.e. about the same time as I started testing) Only about 5 months to go until we can start enjoying the sunshine on a dual carriageway again :-)

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Looks like grumpetto kit.

Aero head = cheating

Looks like grumpetto kit.

You mean CSG totally ripped off GS Metro's style.

Oi, colour version...

Aero head = cheating

I read somewhere that your head is not very aerodynamic at all. To be honest though I would prefer not to wear a lid whilst tt'ing. The archaic rules in Scotland dictate that this is not on.

Am I right to guess that lids are not compulsory for testing in Englandshire?

You mean CSG totally ripped off GS Metro's style.

I had another look at Grupetto and it's quite different. I thought the CS was stacked on the Grupetto like GS was on Metro but it's not actually. GS Metro's kit looks more like the Belgian National Champ strip.

I read somewhere that your head is not very aerodynamic at all. To be honest though I would prefer not to wear a lid whilst tt'ing. The archaic rules in Scotland dictate that this is not on. Am I right to guess that lids are not compulsory for testing in Englandshire?

Aero helmets, as they are used for racing, which do not however meet the ANSI safety requirements, reduce the aero drag by approximately 2% compared to a bald head or a rubber cap over the hair. The Bell Stratos, an ANSI approved helmet, increases the aero drag by approximately 1.3 % over a bald head. Short hair worsens it around 4.6%, long hair around 8.6%. The leather hairnet helmets which can often still be found with racers - although completely insufficient according to ANSI - increases the aero drag by 6.3%. The wide-spread ANSI approved helmet Bell V1 Pro gains around 9.8% compared to a bald head. So far no measurements have been published concerning the influence of beards.
http://www.sheldonbrown.com/rinard/aero/aerodynamics.htm

I'm sure there's newer studies out there and I'm pretty sure they'll all say aero lids are better than a plain old head so long as you keep them level.

Must spread rep :(

Noob question- how do you go about correctly determining the sizing of a TT bike?

Dunno, but this is an interesting read.

http://bikedynamics.co.uk/FitGuideTT.htm

how do you go about correctly determining the sizing of a TT bike?

1: Spend about 12 hours in the wind tunnel with a bunch of stems and spacers to get a spreadsheet of Cd.A vs. position
2: Spend another 12 hours on a Wattbike to get a spreadsheet of threshold power vs. position
3: Combine the two spreadsheets to get a set of predicted speeds vs. position.
4: Select the position from the above tests which gives the highest speed at threshold power
5: Find the frame which gets you into that position with the least equipment drag, the best handling, and compliance with the regulations under which you're racing.
6: Go back to stage 1 when training/ageing has changed your shape and ability to generate power in various positions.
7: Repeat until bored, which could be another 50 years.

Could you lend me a wind tunnel?

You're spending a lot of cash on go faster toys and you're too tight for wind tunnel testing? Tut tut

I know- it's crazy eh?

However, being the meanest man in SE23 I'd prefer to base something on my reach/height/leg length for now, as this is a purely theoretical "what size would I need" exercise, rather than spanking a couple of hundred thousand pounds on some wind tunnel time to get a fit worked out for a bike that I may never buy.

I'll just go and iron my hands for a while.

rather than spanking a couple of hundred thousand pounds on some wind tunnel time

Tunnel time at the Mercedes GP facility is £450/hr, so you're looking at less than £6k even going as massively overboard as I suggested.

Well in that case I look even more Scrooge like, I'll book a four hour session at once.

Well in that case I look even more Scrooge like, I'll book a four hour session at once.

Unless you have already lucked into an excellent position, £1800 spent at the wind tunnel will probably yield bigger time savings than £1800 spent upgrading from Shimano RS30s to Zipp 808s

And it's exactly that ^ reason why when I time trial I only judge myself against my own past performances. If I ever spent that sort of money on a pair of wheels (or even a bike) I'd have to shoot myself in the face.

Anybody wishing to burn off a mince pie or two is welcome at Maidenhead Thicket on Boxing Day
http://www.maidenheadcc.org.uk/node/542

Maidenhead boxing day 10 Mile TT
Fixed commuter, raised the gearing 78 GI
Garmin says bang on 28 minutes. (Strava says 28.23)
Only got in to the very low end of threshold, not trying hard enough.

Pretty pleased with that for a first effort, good to meet mdcc_tester.

http://app.strava.com/rides/2889530

27:58 according to the timekeeper, and that's the only number that matters.

Double weight penalty for me; Pompetamine & Christmas dinner.
You can see laner and his bike in the background.

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I wish I was a) in London and b) aware of this. Would have been a fantastic first TT for me and great fun to be there with Laner and to meet MDCC.

Congratulations Michael, thats a stonking first time.

Does anybody have any suggestions for an upcoming 10 that would be suitable for a first timer?

All 10s should be suitable for a first timer. It's only 10 miles and you're going to set a PB no matter what. The earliest one near here I know of is in March. Check the guide book or local clubs early next year.

Cheers Hippy. Bexley is my closest.

I was nervous about going out last year but after a few trial runs have proven to myself that I shouldn't be humiliated. Now that I know i can manage at least evens I'm feeling a bit more confident to go out there and give it a try. I'm a bit precious like that.