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Video toys on the way

Mum got me a VIRB for my birthday!

I know .. I'll be 43(!) in March, mum asked, I told her, she said yes.  I have a Garmin VIRB Elite ANT+ video camera coming.

Why is this any funkier than my collection of GoPro Hero's?

It does power.  Last week Garmin updated the firmware in the VIRB to store power meter data.  No, this isn't a substitute for a power meter computer, I'm not replacing my Cyclops Joule 1.0's for VIRB's (at 4.5x the price!), but it does make overlaying performance data onto video a lot quicker and easier than it has been 'til now.  The old way, was to use Dashware to overlay power data onto video, but it was a messy, time consuming task.  With the new VIRB update, I can get video data much more quickly combined with power and speed, so it becomes practical to do, maybe even during a training session.  Handy?  Yes, for teaching and explaining what happens in, for example, a team sprint.  We take hand splits with stop watches, but if we have video, with power and speed, we can actually see what's really happening and make more intelligent gear choices and pacing decisions.

Same sort of thing with flying 200's and the like.  I'm excited at what I think we can do with this toy.



SRM battery replacement

Finally some batteries arrived ....

Nic Mark got himself a set of SRM cranks, powercontrol V, single reed switch job.  I've already replaced batteries in the fancier two reed switch special I got last year, which was easy once I found a supplier for the batteries, the single reed switch version is a little fiddlier, but still pretty easy to do.

Photos here.


Now you can buy Anna's helmet

It's not cheap! - 599 euro!  But, it's a very fast helmet.  A Casco-beater?  Maybe Shane can find out for us!


gears go up!

J17's can be strong!

Long have I ranted and railed ... and good news!

J17's are now allowed a 7.0m rollout (~90").



Please, Minoura, give us our rollers back ...

An open letter to Minoura Japan

I have two sets, the VIS has heaps, the AIS, NSWIS, Cycing Vic and WAIS all own dozens of them. Hilton owns at least 4 sets, of the Minoura Action roller.  Why these rollers in particular?  They're not perfect, they have aluminium roller drums with 105mm diameter, which is good, but nasty plastic endcaps that fail with heavy use.  The big plus for us is the way they fold up into a small space and they have a reliable, simple bag to transport them.  I get to carry them around a lot, and the bag, and the trifoldability, is a BIG win.  This is why just about every state track team has heaps of them.  105mm metal roller drums and great transportability.  Got it?

Not that long ago they got discontinued.  Why? I don't know, the replacement is the Moz roller, same trifold frame, but smaller 80mm plastic roller drums (BAD!) and a fancier bag that has a zip instead of a flap.  This is bound to fail in our use-case.  We move lots of these rollers (Hilts' van may have a floor lined with 16 sets of rollers when we travel to championships etc) and anything with a zipper is bound to fail.

So, Minoura, please re-release the Action rollers.  If you want to make them better, replace the plastic roller endcaps with something more robust, but otherwise LEAVE THEM ALONE!


You say you want a revolution

Well, you know, we all want to change the world ...

Tonight at Spin we tested the Lemond Revolution under Dino.

To paraphrase :

It's much harder to spin up than the Kurt Kinetic, but it's too easy once it's going.

That's Dino's thoughts - given that we care about the acceleration phase, this might be a good thing.  It's noticeably less stable than a KKRM, and a LOT noisier (as you'd expect, it's a wind trainer after all, albeit a fancy one).  I will try it under a few other guys and see what they think.




New stuff

I have a Lemond Revolution on order to try out

Ok, we won't get power from it, at least, not acceleration, although it may be calibrated for steady state (enduro) training, but I have one of these coming which will hopefully be in time for this Tuesday's ergo.

Interesting bit of kit ...

lemond revolution

We'll review it once we've tried it out.  Rumour has it it has a decent flywheel in it, and if so, and direct drive, it might be a game changer for ergos.  If they made one with a built in powermeter ...


Peak Torque

How hard do you really have to push

There's an age-old question in track sprint, and it's this : "How strong do you have to be?" or variations on that. Why do we care?  Because, unlike our roadie and to a lesser extent track enduro cousins, we have to push very hard indeed for a few pedal strokes to get up to speed, on what may be a pretty large gear.

No commercially available power meters give the full picture.  Powertap, SRM etc do not report peak torque in a useful way - they report averages (but measure everything, if you know how to ask them the right questions).  Averages for torque are  nice to know, but don't really answer the question.  Peak torque is how strong you are, and that's a very interesting figure to know.

I've been lucky enough to be involved in assisting a study being done around these parts which is looking deeply into the torque requirements of sprint cycling.  It's been very interesting so far and we're lucky to have some very fancy torque measurement equipment available to test some of the squad riders on.  I might even get a go on the thing myself if I'm lucky and they want to get some junk data from an old guy who's broken at the moment!  But anyway, it's proving to be very interesting indeed.  We might even be able to answer the question at the end of it.

Interesting times!



Scatto is good

Especially for junior females

Modelled by Emily, I present the 3T Scatto.


  Compare to her using the Easton EC90's, which were 38cm c-c :


  Much better!

Bear in mind that the camera used to take these shots is a GoPro with a very wide lens, so there is a bit of distortion that makes it look worse than it was with the EC90's


Let's go to the video!

Small cameras .. Nifty

Recently I added an extra video camera to the video arsenal. My workhorse is a standard def Sony VX2100. These babies are the ducks' nuts of SD video cameras, the documentary film makers camera of choice up 'til HD took over, thank you Nick Bird for the recommendation!  I got myself a little GoPro "Hero HD" for a bit of novelty value after seeing some really good kayaking videos shot with one.  If you're into whitewater 'yaking, this is brilliant, these guys have done some good videos but this one's their best ... 

Anyway .. To cut a long story short, I've used the little thing a few times at DISC and at Blackburn to record some tutorial-ish video, flying 200 lines mainly, from a rider/handlebar PoV.  Today I did some rear-facing stuff on the motorbike at DISC so I could see what the guys in the squad were doing while at speed.  My editing is very crude, rough and ready using PowerDirector and I don't spend much time making it pretty, but it's still handy stuff, I reckon.

The lens is a very wide angle (170 degrees in most modes including the default 960p/30fps) so there's some distortion when the subject is close (as they should be when being motorpaced, but SOME OF YOU SIT WAY TOO FAR OFF THE DAMN BIKE! The roller is there for a reason, YOU CAN TOUCH IT!) but even so, it's been quite revealing.  We don't often get to look closely at sprinters under load at speed and everything happens pretty quickly.  The video I'm getting isn't going to make our coaching service 107.65% better, make you 30-40% faster or any of that other marketing bull, but it's a pretty handy thing to have and I'm going to use it quite a bit, I think.


More on food

Hehehehe "more on"

Today my copy of Robb Wolf's new book arrived in the mail.  It's another book on Paleo eating (and a little on exercise etc).  His style of writing grates on me, but the content is excellent.  Many months ago I read Gary Taube's Good Calories Bad Calories, and the whole 'paleo thing' is really an offshoot of, or an implementation of, much of the material collected in Gary's book.

I'm not pure paleo at the moment, but on the whole (80-90% at a guess) I probably am, and it's certainly working for me as it does for many others.  I think, as an eating philosophy for sprinters, it's ideal.  Unlike our enduro cousins who need lots of carbs, we're not chronically glycogen depleted and we don't need mountains of pasta, jelly lollies and the like.  Quite a few of my sprint squad people are going down this path with some significant body-composition changes happening to them.  They might call it "low carb", or say "you've turned me into a carnivore!", but it's working for them too.

And after all is said and done,  steak .. it's just plain yummy!

Round 1 in 2 days.  I'm getting excited!  My new tyre is glued up and will be ready, tomorrow we're painting the lines on the track and doing some very short efforts to get our gearing sorted and lines 100% set. It's all good!



Back on the (old concrete) track

Sunday last (3rd Oct) was the practice day for the Summer Sprint Series.  I'd spent a bit of time at the old Blackburn roundy-roundy-drome doing some weeding, burning weeds, chopping weeds, sweeping etc over the last fortnight but hadn't done a lap as any sort of speed since the last round last summer. 

With a pesky shoulder injury keeping me seated and spinning, I did a couple of demo rides of the two most common flying 200's with a funky little "GoPro Hero HD" video camera attached to my trusty track bike.  These little cameras are brilliant.  Cheap enough to not worry too much about if they get damaged, waterproof, high-def (can do 1080p at 30 frames/second!) and with a stack of clever mounts.  I slapped the camera under my stem, popped on an 86" gear and did some demo laps for the camera.

Here's the video from those two lines




After that, and a warmup sucking the wheel of the ubersprinter for a few laps, it was time to do some practice.  I figured I wasn't good for much, so dropped my gear down to 82" and cranked up the cadence.  I rode a 14.4s flying 200, which was about a second off my best at Blackburn, but it wasn't a full gas effort and was way off the sort of gear I'd normally ride (when I can get out of the saddle to get over a bigger gear anyway, bugger it!).  I'd probably ride 92" or so if everything was working well, and bigger if I felt good and there wasn't much wind.   As it is, I'll be happy if I can hold 86" next week without pain interfering with my ride. We all did a few flying 200's, most of us were way off the times we'd been riding last year.  With no aero fruit, fancy wheels or helmets etc and a strong nor-easter blowing it wasn't all bad.

I did two practice races against Emily, and one against David Thomas, we were all getting the feel for the slacker banking at Blackburn after a winter's training indoors and on the 42 degree timber banks of DISC.  It went well, everyone did improve through the session and I'm looking forward to next Sunday




Stopping the slip

Doing big gear starts on a Kurt Kinetic Pro with the big flywheel

We do a lot of high strength work on Kurt Kinetic Road Machine trainers.  I'm a big fan of these, they work, they're (compared to the BT and Wombat etc) affordable while not being cheap and nasty and there's an option to have a very heavy flywheel.  We use the big flywheel for strength work.  It fits on the "pro" version of the KKRM.  With the Uberflywheel, the total flywheel weight is 18.25 pounds, or a bit over 8 kg. This takes some effort to get going.  The Computrainer that all the enduros rave about would blow to bits with the sprint stuff we do, it's limited to about 1500 watts of electro-magnetic braking and I doubt it can cope with high torque applications.  The only other thing that comes close is the WattBike, but that's not a cheap bit of kit and it's got its own flaws, most glaringly the wrong Q factor for starters, and yes, that can be fixed, but a $3000+ bit of gear should be right from the start!

Like everything, the KKRM is not perfect.  For strength work, we load up with a big gear, for example we sometimes use 53x12 (119") for some efforts.  This isn't really what the KKRM is designed for,  but it is the best simulation of a standing start I've been able to find.  With the superflywheel, it's harder than getting out of the starting gate.  Ie: it's good specific strength training.  BUT the rear wheel of a bicycle, no matter how tight we do up the tensioner, slips.

Until now ...

When I was over in Adelaide at the NTID sprint camp a couple of months ago, I had a look at what the AIS guys use, one of them has a KKRM, but he'd modified it, presumably for the same reason I have now modified mine.  Skateboard deck tape around the roller.  This might shred tyres, but it now means next to no wheel slip and a much better initial first three pedal strokes, as the roller starts turning rather than slipping ,which was the big advantage of the BT and the Wombat etc which are directly chain driven.  I ducked up to Ringwood and bought a sheet of glorified sandpaper from Ballistyx (which is all deck tape is, it's a sticker combined with sandpaper), cut a bit to wrap once around the roller, stuck it on and trialed it last Tuesday at Spin.  Wow.  It works really well.  We'll happy cope with more tyre wear for this improvement in resistance.

So now my kilo and 500m ITT riders (and team sprint starters, ie: me!) have a harder session when we do big gear standing starts on the ergos.

Good stuff!


Houston, we have a (small) problem

Our track powertaps are not quite right

I'll cut to the chase (I'm pretty busy working on sprintTracker, my little python program to track sprinters times etc), I'm responsible for some 10 track modified Powertap hubs, two are mine, the rest belong to the VIS, the NTID and Hilton Clarke.

There's a small problem with them involving the chainline.  We never noticed it on mine because it's only about 3.5mm out and I'm no great torque machine and both my and Emily's bikes have reasonably long chainstays so the chainline problem doesn't really show up. However, under some of the NTID and VIS boys who have real motors we hear noises at high power outputs, so we investigated the chainline of the hubs.

Best illustrated with a couple of (poor quality!) photos :

pt track hub chainline  That's what they look like

campy track hub chainline  That's what it should look like

 As you can see, even with my crappy mobile phone photography and quickly cobbled up bit of cardboard measuring device, the PT hub puts the sprocket about 3.5mm (the width of the lockring) too far towards the middle of the bike.  I think the guys at Wheelbuilder made a mistake reading the width of the hub and assumed that the sprocket was where the lockring is,  which it isn't. Most people would never notice, the 3.5mm deviation is small and under enduro riders would not show up at all, but put them under a big sprinter putting out a lot of torque and it makes noises and runs rough.

The fix is pretty easy, the hubs have a steel axle end cap that you can see in the top picture (with the flat side to allow you to do it up), that needs to be 3.5mm shorter and the other side needs to be 3.5mm longer.  Then, all the wheels need to be re-dished.  Bugger, most of them were put together by Daryl Perkins and he tied and soldered them, which is a PITA to re-do.

Anyway, these things happen and I'm sure the guys at Wheelbuilder will send us corrected end caps ASAP.  They're smart people and proud of the work they do, they'll want to take responsibility for this and fix it.  In the mean time we can machine down the existing drive-side end caps and put washers under the off-side ones.  It's fiddly and shouldn't have to happen but this is prototype and first generation stuff, we expect a few teething issues.  It's the price of being on the bleeding edge.



Enter the Kamm-tail

Everything on bicycles is at least 10 years behind motorcycles and cars.  The Kamm Tail was originally developed in the 1930's in Germany.

Now it's showing up on bicycles!

Our distant cousins over in triathalon-land think aerodynamics matters, and they're right, but it REALLY matters at 60+km/h in sprints.  Will this technology make it into sprint bikes? 


The rumour mill

Filed Under:

It runs hot ...

Trek carbon track bike?  We've seen pictures of Tyler Phinney on one.  Word on the street has it that it may end up in production....

Blackburn club rooms finally getting some new carpet?  Rumour has it it'll be done on Friday!

Fun times!



Powertap upgrades

Steel is real!

The current generation of Powertap road power meters (the wireless 2.4GHz ones) mostly come with an aluminium alloy freehub body.  After not very long this happens to them.  Sucks ... It's because making an alloy freehub that works with both 9 and 10 speed Shimano cassettes compromises the design of the freehub.  Of course, the weight weenies want light hubs ... so for the sake of 80 grams (I weighed both the alloy and the steel freehubs today) all but the bottom end Powertap comes with this stupid alloy freehub.

But!  For around $200 or so (in Australia, from a Trek dealer) you can get the PT Elite+ freehub, which is steel (and ... yes ... 80 grams heavier) and swap it into your higher end hub and eliminate the problem!  Win!  It should not cost what it does, but that's not something your LBS can do anything about, wholesale these things are insanely expensive, but they are available and they mean you can swap cassettes with just the one chain whip!  Nice .. when something works like it should.

Enough ranting .. My PT 2.4 is now upgraded to a steel freehub and I'm happy about it.



Tyres for board track velodromes

There's lots of crashes at DISC, grip is one contributing factor. DISC has no rules re tyres ...

In the UK, at the Manchester velodrome, they have rules about what tyres you may use on the track :

  • Use Continental, Schwalbe, Tufo or Vittoria clinchers or tubulars (black tread only), 21 mm wide or better.

    Recommended clinchers and tubulars











    S3 Pro



    Sonderklasse 165/175



    S3 Lite 135



    Durano T

    22 and 25mm


    Elite 120



    Ultremo R1

    22 and 25mm


    Pista EVO CS




    Pista EVO CL


  • Tyres must be inflated to 8 bar (119psi), and the pressures, and tyre condition checked regularly. Do not use Michelin tyres or any dual compound tyres or tyres with coloured treads. Other tyres and tubulars may in future be recommended after analysis. Do not use tub tape to fix tubulars to sprint rims – use proprietary rim cement.
  • Do not use brand new tyres on the track without first preparing them thus; rub the surface with alcohol or white vinegar or other degreaser before use. Ride the first three laps on the Cote d’Azure or bottom of track.
So ... I don't agree with the contents of the list, no Veloflex Records or Vittoria Diamonte Pro Lights

(which we use), but as a general principle, I think it's a good one.  There's far too many low speed crashes on the boards at DISC and I strongly suspect that poor tyre choice is a significant contributor to this.  I was watching one of the NTID lads trackstanding on the bend last night doing skills work, on a Diamonte Pro Light.  Try that on one of those crappy Michellin Pro3's ... Manchester bans them! :


·         Only use Schwalbe or Continental clinchers or tubulars (black tread only), 23 mm wide. Do not use Michelin tyres. ·         Do not use brand new tyres on the track; rub the surface with alcohol or white vinegar or other degreaser before use. Ride the first three laps on the Cote d’Azure or bottom of track.



You can see the full Manchester recommendations here.  Worth a read.



Trek has a new track bike?

Filed Under:

Spotted ...

New Trek track bike?Many of you know, and if you don't, you do now ... I'm a bit of a fan of Trek bikes.  For a long time they've only had an aluminium frame track bike (the T1).  It seems they now have a carbon one .... It looks like an Equinox TTX with track dropouts.  Interesting ... I have our local Trek rep on the job to find out more.


Equipment, return to sender

Unfit for purpose!

I wrote in my last blog that, amongst other things, it's not about the equipment.

Except sometimes it is ...

It is when the equipment is a limitation.

If you don't trust your equipment, especially in a sprint situation which demands 100% commitment, you cannot perform at your best, and then it is about the gear.  When your equipment is a significant limitation, change your equipment.

I have an FFWD 5 spoke front track wheel.  It is being returned to the local distributor for a refund. I don't trust it.  The first one I got about a month ago, Pete and I glued on a Tufo S3 lite tyre, I took it to DISC and jumped on after some quick photos for Ride magazine.  It immediately launched into a resonating tank-slapper as I got onto the bank.  I took it off, put on the old Bonty front and got back to training and coaching for the day.  Later, Nathan Larkin and I pulled it apart and found that the bearing/axle fit was fractionally loose, and there's no way to adjust it.  Ok, send it back to FRF (local distributor), they send me another one.  This one's still got a little bit of play, but it's better than the last one.  Glue it up, wind it up at Blackburn at round one of the aSSS for my flying 200, I'm 100% committed to this effort and am going absolutely as fast as I can in almost perfect conditions.

At full speed, it does the same thing the last one did, almost putting me over the fence.  I was very lucky not to crash.

We had a look at it afterwards and the bearing/axle interface has play, enough to allow a resonance it seems.  What a seriously brain-damaged design this is.  A ~$3,000 retail wheel which has no way to alter bearing tightness.  The Mavic iO has adjustable bearings, which means manufacturing tolerances (and wear!) can be adjusted out.  Not so this design. It's a POS.  Don't buy one unless and until they redesign the hub such that you can adjust the bearings.

Not that you probably need one anyway, I don't need it, I need something I can trust, which isn't this wheel. If you're thinking about it, think again.


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