[Closed] 2017 TT'ing thread

Bridlington 25 for me. We camped over at HQ last night as it was an 8am start, my club mate who persuaded me to enter got there and realised she'd forgotten her tent poles so went home and left us to it!

Ended up 3rd lady in 1.08.01 - with a 10 second or so delay caused by an idiot driver who was deliberately delaying riders by passing them then slowing right down - apparently he did it to 3 or 4 others too.

More importantly I beat my OH. He is still wandering round muttering about not being a morning person...

West London Combine and club TT champs on the lumpy H25/4 at Great Missingdon. Set off too fast with a sub 11 minute segment (Garmin autolaps on 8.05 km). Settled in for a target of 280-300 powerpod watts, which would produce a 57 (maybe). Segments all sub 13 minutes, despite the bumps. Kept the heart rate up on the downs, and picked it up on the climbs. Almost taken out by a car pulling out from the right, with two miles to go. Finished in 58:07 for a PB and fourth overall. The winner passed me at 32 minutes and finished in 56:00 dead. My minute man finished 6 seconds up on me.

Front tubeless Corsa Speed punctured at 10km, but sealed, and I rode on 40psi. Powerpod registered 303 watts.

ORRL 9-up 25m TT at Weston on the Green airfield last night, brutal wind and rain. We came 6th with 57.02, with 4th-6th super close

As a member of the host club I was one of the starters (3rd man). Some good photos kicking about on FB, most people look like they've ridden a wet Paris Roubaix or a CX race! And having done a grand total of 3 TTs in my life (started dabbling this year at the weekly WotG nights) I seem to have qualified for our team for the Silverstone 9-up in a couple of weeks 😯

And waves at TSY as we met on an Oxford MTB ride many years ago.

Dreaming Tyres crashtestmonkey?

Based on the ORRL pictures I've seen I'm glad I'm not racing that league this year! Had been asked to ride in the FUCT guest team but was racing elsewhere all ready.

Hoping for a fast time on H10/17R at Southmoor this week, a short 21 would be nice.

Front tubeless Corsa Speed

I was looking at the numbers for these, the crr is insane. I ran Open Pave 25s with butyl tubes (all my latex ones had punctures). The potential time saving for the Corsa Speed over a 10 would be 25-30 seconds!

@TSY Didcot Phoenix

@CTM Yep that sounds about right...pretty much had to chisel the crap off my bike! Rear wheel kept sliding out too which was very odd.
Can anyone enter the Tuesday nights? If so, what time is sign on etc. - I fancy trying them as I live in Bicester!

TSY, Indeed it was.

Jb89, open to all. Should be a calendar and details on www.bmcc2000.com but basically it's mainly solo nights (usually 10s) but with some 2 and 4-ups when there are no solos. Sign on is from 7pm, club members get priority but we've never turned anyone away and there's usually more non-club than club. £5 for non-members, tea+cake is a quid, and most of the members hang around after being sociable and they usually get results up online that night.

I'll be riding tomorrow, potentially 19C and light winds (as it's an exposed airfield circuit it's not a fast course according those who know).

I was looking at the numbers for these, the crr is insane

There is a Vittoria recommendation that comes as a package insert NOT to run them tubeless with full carbon rims, which rather defeats their purpose IMHO. The sharper edged carbon will destroy the tubeless bead and sidewall. There have been quite a few failures. Hence my Hed wheels - going for a Jet+ with the alloy rim next. I've run the Corsa G+ since they were released. These are a step up in terms of speed.

I want to write a TT related update but I don't think there are any more TTs here so all I can report is that I've turned my TT bike into a bit of an abomination. Aside from the lack of gears it seems to work quite well though.

[img] [/img]

Dat stem! 😯

[img] [/img]

How do you calibrate your powerpod TiRed? Is there some protocol to do a crr/cda ramp where you do laps of ascending power+speed so that the PP software can isolate your rolling resistance from your air resistance?

@CTM - Great! Legs are fried but might pop along on the road bike...TT bike has no cables at the moment which could be problematic! Looking a bit drier than last Tuesday that's for sure!

The only good thing about that P3 is that it's not mine.

I got kitted up in all the slippery kit, then rode a 100km loop with five laps of my favourite TT circuit (Drift Road near Windsor). The Powerpod algorithm already has been fed a good estimate for Crr and my weight including bike. It then estimates power for rolling resistance and gravity based on inclination, and uses a known value for TT CdA of 0.23. Once home it uses an option to check calibration. This adapts an aero scaling factor and friction to ensure that the average wind is zero. After all its a closed route. Once done this saves a new profile that I load back into the powerpod and use.

I check the predicted power against bike calculator and others for measured temperature, pressure and humidity, to find air density. Powerpod measures air pressure and density too I believe. It's pretty cool

If paired with a force power meter, the software will take power from that meter as the truth and do the reverse calculation to estimate CdA in during the ride, adjusting for gravity and friction. That is an extra feature you have to buy.

I'll probably buy a single sided Vector because my vintage Dura Ace cranks can't take my Stages, then do this calibration to estimate real CdA. This is where I think the real value of Powerpod lies for TT. It's basically half the price of an Aerocoach session, with much of the functionality. Provided you have a nice test circuit like Hillingdon to ride 10 laps.#

You can also calibrate your powerpod once against a known power output from a force meter and remove the force meter.

#you can also use the Chung method with a power meter and virtual elevation too, but I think the powerpod is easier.

Pic from the ECCA 10 Champs last Sat. At least I looks like I'm giving it a proper crack.

[url= https://preview.ibb.co/ff9Hqv/FPMatt_S6810_copy.jp g" target="_blank">https://preview.ibb.co/ff9Hqv/FPMatt_S6810_copy.jp g"/> [/img][/url]

Stem is set at -40? - I really need a proper TT bike!

Club event on V226/V212 for me last night. Officially 15 miles but for our club events you actually do 15.2 because the timekeepers prefer to do the finish timing by the start rather than going up the road a bit 😉 to add some spice my OH was off a minute behind me looking for revenge after I beat him in a 25 on Sunday.

He didn't pass me but did do a slightly faster time than me. I'm still pleased with how I rode though. I was aiming for 40 minutes and would just about have got there had the finish been at the 15 mile point. I was the only woman doing the 15 (apart from a guest pro triathlete but she doesn't count :wink:) but beat all the other women through the 10 mile split (they also run a 10 at the same time and take 10 mile times for everyone, you can then carry on for the extra 5 if you want).

Average power about 10w up on what I have been doing for 25s.

Nice one, hjghg5 - seems like you're posting about an improvement every week. 8)

I'm taking to the road for my first ever ride on a TT bike tomorrow (practice for 1st ever TT next week - maybe)

Any tips ?
(I've had it on the turbo so I know it sort of fits)

Forget fit, have you actually ridden it on the road? Can you control it on the aerobars 😉 . That would be my first tip - scratch your nose whilst leaning over. Plenty of other tips will follow, I'm sure. The best is don't start too hard.

Stem is set at -40? - I really need a proper TT bike!

matt, the position looks pretty good and not dissimilar to mine, apart from being able to change gear, you won't gain a lot more speed. Mind you, changing gear is nice 🙂

have you actually ridden it on the road? Can you control it on the aerobars

😯

matt, the position looks pretty good and not dissimilar to mine, apart from being able to change gear, you won't gain a lot more speed. Mind you, changing gear is nice

Indeed. Changing gear has to be done only when absolutely required. PITA!

And I need all the speed I can get - I found out on Sunday that Gray has been testing in a tunnel. And there's me with Open Pavés and a home-made disc cover. 🙄

All the fast boys are also using custom Nopinz club kit and not the club skinsuits. I feel cheated. 😆

No comment (from the nopinz custom tripsuit owner). He was on form in tonight's vets circuit race.

You know that etap would be a nicce upgrade, or just a set of bars. A clubmate has some Hed Corsair deep drops that would retain your position and be a direct swap.

The biggest pain is that it's my only race bike, so it takes hours of pissing about to change it from road to TT setup all the time. Not only would having a proper TT bike allow me a bit more tweaking room on position, but it would also mean that I could have it set up and ready to go all the time.

Buy used. Mine was £400 off Ebay. A nice cheap TCR aero or [url= http://www.ebay.co.uk/itm/MENS-VINTAGE-DAVE-HINDE-TIME-TRIAL-FRAME-AND-FORKS-BICYCLE-50-5-X-55-COLUMBUS-/192182198975?hash=item2cbef3a2bf:g:o9QAAOSw~FJZEX-Q ]retro steel[/url] will retain your position, you can move bits across, and still have change for some nice bits. I deliberately didn't go for the latest and greatest. Position first, then some nice kit, and finally, maybe a carbon frame when I'm down at the 21 minutes!

The nice thing about TT is 1) they are flat so weight is less of an issue and 2) bikes are cossetted so tend not to see a lot of use.

Had some strange fortune with having a bike recalled and a shop bending over backwards to provide me with a (better) alternative a couple of years back, been adding to it with wheels etc since...

[img][url= https://preview.ibb.co/iGG60v/TT.jp g" target="_blank">https://preview.ibb.co/iGG60v/TT.jp g"/> [/img][/url] [url= https://imgbb.com/ ]image upload[/url][/img]

Good to meet you jb89 and hopefully see you at WotG again (maybe on your full TT bike when you're back into it). I'm not an expert in power metres (only got mine recently) and I know comparing them is a rabbit hole, but we are similar height and build and both on road bikes and we set very similar times, but the power you mentioned your SRM showing was about 50W higher than my 4iiii. I had a play on bikecalulator.com and it's prediction was only a few seconds different to my actual time with my recorded power.

Re BikeCalculator.com

I recently entered the stats for a steady road ride measured power with my now corrected Powerpod. It measured 179w average, Bikecaclulator shows 177 without the average climbing grade as Strava doesn't show this (Isaac probably does) - amazingly accurate for [i]actual[/i] power and restoring my faith in the PP. But strava's [i]weighted[/i] power is 209w.

I'm guessing strava's weighted power should be ignored?

similar height and build

Similar or the same?

There may be some deviation in the power readings. Were both your PMs zeroed before the start? I believe the 4i automatically does temperature compensation. I know the old SRMs didn't - not sure about the latest ones.

Aero is a huge factor at TT speed. Someone who is on the hoods, elbows bent, chewing the bars will go way faster for less power than someone who has the aero capabilities of a brick.

Last year in our club road bike TT series one of the top TTers in our club came (low 19s for a 10), 808s, wore his Bambino, etc, etc, put out his second best ever 20 minute power ever and I beat him by over 30 seconds. Body position is everything. A month later he rode 20W less, I did 10W less, and we did the same time.

EDIT: As an addendum, I checked out the details for the guy who won most of the rounds. The second round he did 400W for a 20:12. The next week he said "I'm going to really concentrate on getting aero this week". Did 370W and clocked 19:38.

I'm guessing strava's weighted power should be ignored?

Weighted power is like Normalised Power - When power fluctuates, it's a measure of how hard the ride would have been if you rode it at steady power rather than up-down-up-down.

I don't think Strava publish their algorithm though, so I ignore it and use NP from Golden Cheetah.

@TSY - Bike looks sweet. 8)

*jealous*

Likewise CTM! Will definitely be back!

I noticed the power difference too! However, I was going for an all out power test and ignoring any aero-ness, which could make a fair difference as matts says. Plus, I think I'm a bit wider/fatter than you! 🙂 Still, seeing as my SRM is 2nd (or 4th or 5th!) hand, I should probably get it calibrated.

My winter bike is pretty ineffecient too...knackered BB and freehub probably didn't help! Still, served a purpose!

yeah, your lights probably cost you more watts than they put out 😀

Someone who is on the hoods, elbows bent, chewing the bars

that would have been me... I'm new to PMs and TTs so learning and getting interested (dipped in and out of this and the Stages threads on and off for a while). Possibly because it's a TT around a flat airfield course, but my Strava weighted power and straightforward power was only a couple of W different.

And from a handwaving, anecdotal perspective it's interesting to compare powers and times. Three of us in our club put out very similar powers, I'm ~2 minutes quicker than the guy with the bad back who is quite upright even on the drops, and ~2 minutes slower than the guy with the full TT set up.

yeah, your lights probably cost you more watts than they put out

Possibly because it's a TT around a flat airfield course, but my Strava weighted power and straightforward power was only a couple of W different.

And from a handwaving, anecdotal perspective it's interesting to compare powers and times. Three of us in our club put out very similar powers, I'm ~2 minutes quicker than the guy with

Better safe (safe to have a long list of excuses!) than sorry!

Yep without accelerations or freewheeling both average and weighted/normalised should be the same.

Interestingly on that bike calculator site, my details with 328w gave 23.45 on the drops, 25.43 on the hoods, and about 50:50 gave me 24.40 in practice, which seems about right! I'm impressed with the website!

As you have a power meter, you can test your CdA using the Chung method.

Loads of factors make a big difference. 'In the drops' is wildly varying between riders as people have big differences in how aggressive their bike fit is.

Clothing and helmets also make a big difference. Skinsuit vs regular jersey and bibs could be 10W. Skinsuit to one of the crazy supersuits could be another 20W!

Are you using the bikecalculator app or the web page? The App has additional settings for transmission, friction and aero efficiencies on a second menu page. I tune my TT bike wit 90% friction and aero, to match PP. Then I just race against PP output. Reproducibility is what matters, not absolute value.

That said, I've invested in a proper disc wheel for Cambridge and will be getting another force PM for the TT bike too.

Kryton, I'm glad the PP is giving you believable numbers now. I still find switching between bikes to be a pain; the red pod never leaves the TT bike, but the black one moves around a bit.

Kryton, I'm glad the PP is giving you believable numbers now. I still find switching between bikes to be a pain; the red pod never leaves the TT bike, but the black one moves around a bit.

Mine identifies both bikes ok. To avoid upsetting that ive set the profile - in isaac - the same avoiding changing the cda. So now both profiles have the same rr, tarmac etc the only difference being bike weight and aero numbers.

What might help - in learned from Velocomp Technhelp that each time you make a manual change Isaac creates a new profile, so you need to look at the latest profile related to your speed sensor, not necessarily the one you called "Shorter TT bike". To be certain on my road bike in did a new test, noted the uploaded profile name/date, edited the CRR to the revised value (0.0060 for me) downloaded it to the PP, which created another lrofile, which I made a note of...

Now its within 2w of bike calculator thats good enough for me.

What might help - in learned from Velocomp Technhelp that each time you make a manual change Isaac creates a new profile, so you need to look at the latest profile related to your speed sensor, not necessarily the one you called "Shorter TT bike". To be certain on my road bike in did a new test, noted the uploaded profile name/date, edited the CRR to the revised value (0.0060 for me) downloaded it to the PP, which created another lrofile, which I made a note of...

Fast, innit ?! 😀

Just been out for another little set-up & learning ride. 6 seconds faster than my pb of 6 minutes on a longish, flattish stretch of road - previous pb was 13mph tailwind, tonight was a 8mph cross. Also got a joint KoM on a short local stretch

Cheating, really, but I can live with myself

No racing for me this weekend but on Thursday I hit my target time for the season on our 12.5 mile club TT course - the first year I rode my best time was 34.15 and last year it was 34.08. I really wanted a 33 this season and managed it with 33.50. really pleased with that!

Having a few weeks off to go on holiday with just one spoco on Wednesday before we go. Will be nice to have a bit of a break and just riding for fun!

Anyone ridden a 100 on J4/18 before?

I've just entered (don't really know why) and it certainly looks like an 'interesting' course...

How do you train for a 100? Just lots of tempo rides? I've done 2 hours tempo before, but never more, so I'm thinking just build that up to 4 hours in stages? Any advice please?

New 22:34 PB for the Westerley 10.3 tonight. Position has been seriously fettled and the weather was warm and still. Most unusual. Better yet, this was without the disc wheel that is coming, nor the new saddle. 310 watts predicted my time to within 10 seconds on bike calculator, and also at a 175 watt fettle ride afterwards.

Should be ready for the Chrono on Saturday. Off about 12:30.

You know that thing about forests and nobody hearing a tree fall ?

Did my noob (10) TT tonight and forgot to record a GPS 😳
I did 26:16, winner 23:03
Was a bit too worried about blowing up to properly push (and had never ridden the TT position for more than 10 minutes before today) so obvz, ...

I can go faster [i]next [/i]time 😆

Well done, which course?

I really want to get out at some point this season, but getting virtually no training. Two kids is much much harder than one....

p164, Lyndhurst. Nice quiet roads but a tad hilly for my liking

The good old triangle of pain 🙂 keeping meaning to do an official run there, when I get a spare hour I'll take the board an tt there for its maiden run.

The good old triangle of pain

have a look at the south dc site - there's about 3 runs per week on that course. Think I might do the 15th if I get a pass and the weather's good.

(was my bikes 3rd ever run - bit noisy gearing-wise, and some trimming needed for my mast-like steerer but otherwise worked well.

I find I'm MUCH more comfy with elbows & hands well apart rather than both central - I'm sure it's a bit less aero but I reckon I'm able to pedal much harder that way. Does anybody else do that ?