Wednesday, January 27, 2016

Visiting the ARC Wind Tunnel

Today was a fun day - the Auto Research Center (ARC) hosted their "Bike Fitter Appreciation Day" at their wind tunnel in Indianapolis.  Wind tunnel testing for cyclists is a relatively new adventure for them, and they had this event to help spread the word.  I am really grateful to have this opportunity, and it was a really cool experience.  A big "thank you" to Tim Jennings and the rest of the ARC crew for inviting us.  Being a cycling nerd and a motorsports dork, I totally geeked out.

Getting Brent's bike ready for his run.
The black table is specifically installed for cycling tests.
The event started at 8:00 AM.  I was the first one there and the only guest there for about an hour before another fitter showed up.  So, I had a lot of time to talk to the staff, hang out in the tunnel, and ask annoying questions about every detail of the tunnel.  They showed me how they configure and calibrate everything.  Another fitter, Brent Emery from Milwaukee, was scheduled for 9:00 AM.  After some time getting his bike set up, we got to watch him do a run.  Brent happens to have won a silver medal in the team pursuit in the 1984 Summer Olympics.

The wind tunnel is pretty cool.  It was originally designed for racing and automotive purposes.  When not configured for bikes, they can test 1/2 scale cars and 1/4 scale semis with a rolling floor.  For cycling, they go 30 mph, but for race cars, up to 118 mph.  It uses a 451 HP electric motor, and to quote one of the technicians, they're "responsible for most of the blackouts in the immediate area."

For cycling purposes, the wind tunnel is set up with the black table, as shown in the pictures.  The rolling floor is not used, and the tunnel is calibrated with the table in place, so that is basically "zero."  The table is equipped with 6-axis sensors to measure several parameters.  For cycling purposes, we're mostly concerned about the following terms:

Drag - The force opposite the motion of an object.  We tend to think of this as a bad thing, and a bike/rider's drag is expressed as CdA - the drag area.  We can also think of this as how many watts we need to go forward.  A big person will require more wattage than a small person to overcome their larger CdA.  The ARC wind tunnel is accurate to within .25 watts.  The main objective of wind tunnel time is to find ways to reduce our CdA so we can go faster with the same power output.

Yaw - The angle at which the wind hits the cyclist.  Zero degrees of yaw is wind coming straight on.  This is what you would experience riding on a completely windless day.  Most cyclists don't get perfectly windless conditions, and it is common to experience 15+ degrees of yaw at normal riding speeds.  The drag on a bike and rider will vary based on the yaw angle.  The ARC table can emulate up to 30 degrees of yaw.

The ARC table has two mounts that replace the skewers, and rollers to spin the tires.  They will typically spin the tires during a test, and usually discourage riders from pedaling because the body movement makes it difficult to get consistent measurements.

A peek inside the control room.
Tim also gave me a tour of most of rest of the ARC facility, although the doors to the 7-post shaker rig and their drivetrain dyno were closed, meaning something secret was going on in there.  I did get to see the inner workings of the tunnel itself including the motor, cooling for the actual floor of the tunnel (the downforce of race cars will create a lot of heat on the rolling belt and the supporting structure and instrumentation), and the stuff to control humidity.

I also got to see their rapid prototyping room.  They have three 3D printers, and they actually had a few interesting parts looking around, mostly parts used to mount a race car or semi model and control it in the tunnel.  The race car models are mounted to a device called a "sting", which hangs down from above the tunnel.  The sting includes instrumentation and motor controls to allow them to do stuff like emulate braking or turning to see how those changes in angles affect the aerodynamics - downforce, drag, etc.

This was really a great experience, and it's nice to have such a facility nearby.  Wind tunnel time is not cheap, but if it is something you are interested in, drop me a note at and we can see about doing a session.  In the meantime, you can learn more about ARC here:

Thank you again to Tim and the rest of the crew at ARC for a great learning experience!

Wednesday, January 6, 2016

A Closer Look at Dimond Bikes

At Vector Cycle Works, my focus will always be on being the best bike fitter I can be, and provide the best service I can.  Part of that service involves making things more convenient for people, so I've become a dealer for a lot of products in order to better serve my customers.  I don't want people to ever think I'm trying to push them into a certain brand because I sell it - I am here to help folks make an informed decision about what is available to them and help them find something that fits their needs.

When it comes to bikes, I keep a database of a lot of different bikes available via local bike shops and the Internet.  The Internet has reshaped how people buy cycling equipment, and the industry is changing accordingly.  More manufacturers are going direct-to-consumer (Trek is a recent big announcement).  Shops like mine need to be able to adapt to that - if somebody wants to know if a bike that they found online will fit them, I'll find out.

With that said, I'd like to introduce one of those brands that might fit my customers:

Dimond Bikes
One of the bicycle brands that has really burst onto the scene in the last few years is Dimond:

Dimond is the brainchild of TJ Tollakson, a professional triathlete and the founder and CEO of Ruster Sports.  Ruster Sports not only makes the Dimond, but they also offer their Hen House bike travel cases, as well.  The company and all manufacturing are done in Des Moines, IA, so you're looking at a made in the U.S.A. bike.

The Dimond bike is currently offered in one model, which is a unique-looking bike that appears to be missing a few parts.  The classic "double diamond" frame design has been thrown out in favor of a beam design.  The "Dimond" name is missing an "A" in reference to that missing "A" of the double diamond frame.  Cool, huh?

The concept of a beam bike is not new - Zipp, Softride, and others were making something similar before the UCI banned them in the late 90s, effectively killing the beam bike market.  But, because triathlon rules are more open, the concept has been coming back, with great results.  At the 2015 Ironman World Championships in Kona, Hawaii, Maik Twelsiek had the fastest bike split of the day on his Dimond.  The removal of the seat post and seat stays helps aerodynamics.  An added benefit of this design is the ride - the lack of a seat post helps to provide a smoother ride.

Dimond bikes are high-end, made-to-order bikes and offered direct-to-consumer.  Having talked with the good folks at Dimond, they care about their customers and want to get to know you.  To help reach out to consumers, Ruster Sports have put together a network of professional bike fitters and shops who can help guide you in the Dimond purchase process.  I am excited to be part of that network, as it fits into the Vector Cycle Works business model nicely: it's all about "fit first" and puts you in the driver's seat during the process.

The "Fit First" Process
If you are in the market for a new bike, you can come into Vector Cycle Works for a sizing, which involves discussing your needs, goals, preferences, and budget, and getting you on a fit bike to find your fit coordinates.  The nice part of this is that we are not dealing with the limitations of an existing bike or trying to make something work that maybe shouldn't.  We're starting from scratch with a clean sheet of paper to find your ideal fit.  After we are done, I will provide a list of different bikes that will fit you, using different stem and bar configurations, as needed.

If a Dimond bike fits you and your goals, the next step is to work with Ruster Sports to configure your ideal bike.  Dimond bikes are offered in two builds - the Race Build and the Premium Build.  Dimond bikes are also available as a frameset, which allows us a lot of flexibility.  Ruster Sports are flexible in their component selection - perhaps we sized you up with your favorite noseless saddle and they can accommodate that with the build.  They will also do custom paint, if you want something that really reflects your personality and sense of style.  Dimond backs up their bike with a 6 year warranty.

We can also build the entire bike up to your specs at Vector Cycle Works.  Perhaps you want to use your saddle of choice, the bars we sized you with, and a Power2Max power meter.  Ruster Sports can custom paint the frameset and send it to Vector Cycle Works for the final build.  You can truly create your perfect dream bike.  You can see some beautiful custom Dimonds on their blog:

Is a Dimond In Your Future?
Buying a Dimond is not for the instant gratification type, but good things come to those who wait.  Ruster Sports and Vector Cycle Works are not advocates of having a huge inventory of bikes, so I don't have one of each size available for a test ride.

So, how do you go about riding one?  The Dimond Van is out and about, touring the world.  You can find the Dimond Van at different triathlons, and the plan is to schedule a visit at Vector Cycle Works sometime during 2016.  Like Vector Cycle Works on Facebook or sign up for the mailing list so you can be the first to know!

In the meantime, schedule your sizing session at Vector Cycle Works and find out if a Dimond is right for you!