Junior Track Cycling

Junior Velo’s first product review. It may or may not be the last…

My son has been training with a Power Tap Pro rear hub on the road for the last half-year or so. With track season (still in Summer for juniors in the USA) on the way, I was curious to see what power he’s producing on the track.

There were several possible solutions. Ergomo, SRM, and Polar all work on track bikes with less modification than the Power tap, but each has its own drawbacks. Admittedly, the main drawback of SRM is the price, but that was a factor. No free products for review at a small operation like Junior Velo.

The only good conversion option I found was available from WheelBuilder.com. They package a Surly Fixxer cassette-to-fixed converter with a custom axle designed to work with the PowerTap hub.

Installation is fairly simple. If you can remove and replace an axle on any hub, you can handle this one. You just need cone wrenches, a 10 mm Allen wrench, and a regular wrench to fit the locknuts. I won’t give instructions, because they come with the kit. One thing I wondered about, and can now answer, is how much re-dishing the wheel will need. Our wheel (Mavic Rim, set up for Shimano 10-speed) only needed about 1.5 turns on each spoke nipple to re-center it. That means you won’t need to buy new spokes in most cases. Of course you can’t do this blindly - have the work done (or at least checked) by a pro unless you have built wheels before.

Another issue for power measurement on track bikes is what happens when you put back pressure on the pedals. With no coasting, the power measurement device is going to detect some kind of stress. Will that register as positive power, zero, or negative? Will it break something? The answer for Power Tap Pro and SL hubs (or at least the computers they come with) is that you have to read the manual and use the manual calibration option. This prevents the automatic calibration from being confused by back pressure. I’ll add to this article when we see what the data actually look like.

Wheelbuilder.com Power Tap Track Conversion

Here are the pros and cons I have collected so far:
Pro:

1. As easy a hub modification as you could ask for.
2. A lot cheaper ($100) than a new system, if you already have a PowerTap system.
3. Spacers are included in case you need to make this work on a road-spaced frame.

Con:

1. The axle is too long. They try to cover everyone’s needs with one axle, rather than offering a standard track length. Even on a bike with fat Aluminum dropouts, we will need to remove about 1.5 cm of axle. To do it right, you need a threading tool to repair the damage you do with the saw. For $100, they could offer a choice of sizes.
2. It’s just a little wide. I had to discard the thin washers which go inside the locknuts.
3. The axle nuts provided are the cheap type which turns all in one piece. In my opinion only the type where the wide part which contacts the frame turns separately are worth having, due to reduced damage to the dropouts.

I’ll add notes if we learn more on the track. By the way, the picture shows the untrimmed axle, but I have already replaced the new axle nuts with used ones of a better design.

The promised notes:
We tried out the PowerTap in a workout yesterday. Pursuit was on the menu, so the screen shot below is a pursuit-like effort. It’s not a true standing start - just a slow roll into a standing acceleration.

CyclingPeaks Screen Shot

The system seemed to worked well overall. In the screen shot (click for a more legible size), you can see that power is shown as zero when the rider is slowing down before the effort - he was definitely putting back pressure on the pedals at that time.

There were a couple of oddities. The two spikes in the cadence (upper, green) line don’t make sense. Either the system switched between hub-based and crank-based cadence detection or it just plain produced some wrong numbers. The computer also reported impossibly high speeds at first when I forgot to turn the power feature on at the beginning of the workout (the PowerTap had recently been used as a bike computer/HRM without the hub). That was resolved when the settings were correct.

This graph doesn’t show the regular turn-straight-turn oscillation of speed shown in some widely circulated power meter graphs. I think that can be attributed to a windy day and a lack of formal pursuit work since last year.

Thanks to Barry Langley there are some new velodrome locations in the database. Most are in Australia, plus one each in Milan, Bordeaux, and Zurich.

The most interesting is the Joe Ciavola Velodrome at DISC in Melbourne. Apparently Google Earth doesn’t show the same images to all users. The old file would send users to a view of the complex under construction, but Barry was able to see the completed building. The Google Earth velodrome locations file now includes an overlay of the more recent image. You can also view the velodromes (without the DISC overlay) on Google Maps or Yahoo! Maps.

The Junior Velo database is now up to
82 velodromes in 27 countries [98 in 29 as of 4/27/2006] [108 in 29 as of 5/1/2006]
1,001 riders in 47 countries
2,226 individual results from 74 events

By the way, the velodromes are now being returned in alphabetical order for Google Earth. The older form made a better “flying tour” but the new way is easier for finding a particular velodrome. If there’s demand I could provide an option to go either way.

Hi again to the readers of JuniorVelo.com the only blog dedicated to sharing the news and information about Junior Track Cycling.

After my little diary from the 2005 Junior Track Worlds last summer, some people wrote me and talked to me about it, saying that they hoped I would do it again this year.

Like Steve Ryan our blog administrator, I will be following Junior Track Cycling mostly until my son graduates after this summer so if Steve will permit I will report again next summer from Gent, Belgium to keep you up to date with stories and photos from the 2006 Junior Track Worlds.

But this is not my point today. For now I want to report on a fantastic Junior track event that we went to for the last 2 years. We are just getting back from the Alkek Velodrome in Houston, Texas where was held, last weekend, the Nicole Reinhart Junior Cycling Classic.

Under a permanent sun (sorry about your weather in California, we got the same in Canada these days) and more than 80 degrees, 50 Juniors from all over America and Canada attended the 2 day pre-race camp held under the supervision of coaches from Canada and the USA and competed on the track in 2 categories, 10 to 14 and 15 to 18 years old.

Organized masterfully by Kathy Volski from the city of Houston and sponsored by the Nicole Reinhart Foundation, the event attracted Juniors from Texas naturally but also from New-York state, Pennsylvania(Trexlertown), California and Canadian provinces of Québec, Alberta and British Columbia making it a truly international event.

Everybody had fun, honing their skills at this early point in the season and despite this fact we had some pretty good times as you will be able to see if you follow this link. http://www.houstontx.gov/alkekvelodrome/Results/NRJCC.htm

I include some photos so that you see the impressive number of racers present. and notice their good spirit. Juniors can have fun and compete even when the are no Elites present to compete.

Hope to see you next year at the Nicole Reinhart Junior Classic and it is a ”rendez-vous” as we say it in Quebec if Steve will permit me to report from the Junior Worlds in august.

Robert Leroux

Part of the Canadian Team with Lawrence Leroux from Quebec, Monique Sullivan, Eric Smith, Spencer Smitheman from Alberta and Cody Campbell from B.C.

The group picture with Kathy Volski holding the Nation's Cup won this year by Canada. You readers from California may recognize Shelby Allen and Katherine Fiedler from your ADT-Home Depot velodrome in L.A.

The coaches that made the camp and the event possible. From the left Leigh Barczeski (father of sprinter Benjamin of the US Elite team), a coach from the Alkek velodrome club (sorry about the name), Jayson Gillespie from the Olympic Oval in Calgary, Alberta, Kathy Volski the organizer, Coach Bob from Trexlertown and Vincent Jourdain Developpment Manager for the Canadian Cycling Association

Racers Eric Smith from Calgary (in the background) and Lawrence Leroux from Quebec(in the foreground) warming up before the Junior Men 15-18 Sprint final

This was our first really good turnout for the Spring, thanks to especially wet weather. 11 riders, plus parents and siblings found the back way into the velodrome and got rolling.

We had some regulars, familiar faces from the past, and several brand new riders. Keeping such a diverse group active kept us very busy, but it’s always worth it.

Is this Track or Cyclocross?

On the Track

Many of the Juniors who Rode on Sunday

Claire is Only Happy Going Fast

Tyler

Daniel Goes All Out for the Falling Drill

Vanna the Lap Card Girl

If some of the pictures look a little odd, it’s because I handed off my camera to someone else and didn’t notice it was in full manual mode. Some of the shots were subjected to a lot of processing.

Quick note - there is an updated flyer for the West coast road development camp I mentioned earlier. This one is in Word format. If you can’t read it you may need to read the old flyer and then contact the organizers to check on any changes.

The one change I noticed immediately is that the NCNCA Junior Point Series and SNCNA SoCal Cup races are not listed as qualifying events in the new flyer.

This is a track angle to this story. I am told that they are trying to encourage track talent to attend these camps. If you are a trackie who doesn’t normally give priority to road camps, you might want to consider this round.