Volume 1 / Issue 010

Thanks to Dave Powers of Serotta for calling and telling us what he thought of our blog. Dave said, “Part of my job is to keep on top of all our Serotta dealers and see how they are marketing themselves in this new economic envrionment. You guys are the best I have seen with your website, blog, Flickr, Facebook, Twitter and LinkedIn sites. This is really hard work and you will get a great payoff.”

Thanks, Dave!
Feature Article – KGS Bikes fitting vs. Retul – the difference between a fitting tool and a fitting system

I recently received a call from a client in Dallas who noticed that one of the local stores is installing the Retul 3D Motion Capture System and wondered if it was better than the fitting she received from KGS Bikes. The explanation is a little more involved than a Q&A question so I decided to bump my scheduled ezine article for this one.

The KGS Fitting System, those by Serotta, WobbleNaught, Carmichael, Specialized, Cyfac, Body Scan, Fit Kit and others, use a procedural system that gets a specific outcome and these may or may not even use the data generated by a motion capture system.

Retul has become the gold standard in fitting tools in the past 18 months. The reason I say it is a fitting tool is that Retul can be used with any fitting system. It is a 3D Motion Capture System that can accurately measure sensor points which are attached to rider or are indexed to a bicycle.

Retul has a competitor in Dartfish, which is a 2D motion capture system that I own. I am planning on purchasing Retul to augment my fitting services so here is an explanation of how I deal with fitting systems and motion capture systems. The crosshair laser that I use to measure bicycles is another reference tool that is independent of the fitting system. It helps to separate the two as there is overlap and thus room for confusion.

Fitting Systems – KGS vs others. Many of the fitting systems on the market today feature equations or benchmarks that a rider should use to calculate the best way to fit a bicycle. Fit Kit is one of the earlier systems that uses a plumb line to determine Knee Over Pedal Spindle, WobbleNaught uses 33 different measurement points of the rider and the bike to get a computer generated setup for that individual rider and that individual bike. Carmichael uses angles and geometry to assure that an individual is set up within an acceptable range of angles on the bike. Serotta and others use a combination of measurements and riding on either the owners bike or a setup bike.

What separates the KGS Fitting System from the others are two specific processes:

1. I have developed a system of finding the best, most efficient and balanced position for an individual using my custom setup bike, through scientific analysis using a step by step approach to find that perfect setup whether the rider is young or old, fit or unfit.
2. The use of a setup bike with a power meter, that is 100% infinitely adjustable and capable of producing the workload that you as the rider really produce on the road, is critical. My system determines a proper bike setup, rather than a setup based on the limitations of a specific bike.

Fitting Tools – Setup bike. The setup bike was just described and is the core of my fitting system. It has road, mountain and time trial handlebars, different saddles, adjustable cranks from 150-230 mm and almost all modern pedal systems. Since the bottom bracket is the datum point, every other conceivable position is determined by the location of the saddle and handlebars. Since all riders interface with the bike in exactly the same place, (pedals, handlebars and saddle), if the setup bike is able to be positioned to find the rider’s best position it can be found, documented and repeated.

The setup bike is not the system any more than one’s bike on a trainer would be. In fact, my system is good enough to find the perfect setup even if it would be difficult to build a real bicycle with those specifications. This is because I don’t assume that the bicycle industry has created a stock frame for you, I assume nothing. When we get through the fitting process we know exactly how to build a frame that is perfect for you, or to specify a stock frame that works with your body.

Cross hair laser – This fitting tool is what I use to accurately measure the handlebars and saddle relative to the bottom bracket. These lasers do nothing but project two lines into space, but the accuracy attainable from this device is fantastic.

Dartfish Advanced Video Analysis – I bought the Dartfish software and used it with my fittings for a few years but found that the only thing that really worked well was the ability to show ankle placement and the time it took to show the client problems was better spent in showing a solution rather than highlighting the problem. Dartfish is a great tool and some clients can benefit from it but most are better off letting me show them how to get better form rather than see how bad their form is in the first place.

Retul – The Retul system is a 3D motion capture system. The reason I am getting one is the ability to capture the fitting session and not only save that data but analyze it with other setup data. I have the ability now to get people setup properly on the bike. That is not the point. Having a system that gives me better resolution of all the aspects of a rider’s position and being able to save it is important. Another part of the Retul system is a sensor that can be triggered when it touches parts of the bike so the critical dimensions of the setup bike can be captured more quickly and with the same accuracy that I use now. I can save a few minutes doing documentation which usually means I get more time to spend helping the client with specific problems.

In summary, a bad fitter will not do a significantly better job with Retul. All the fitting procedures and knowledge that the fitter used prior to the acquisition of Retul are used after the device is purchased so many bike shops are still stuck with the age old discovery: Bike fitting is not easy.

It has taken me years of study to get really good at bike fitting and I still learn things every day. I feel lucky to have a studio that I can use to really do a client some good. I can’t speak for other shops and studios, but I work not only hard but as smartly as I can to put the client first and get an awesome outcome. I can’t wait to get my own Retul system but the fact that I just have my knowledge, skills and setup bike means that current fit clients will get what they want and need, which is a custom setup that works for them.

At the end of the day, I still find a lot of stock bikes don’t fit grownups well. It is irritating as I have a lot of educating to do when people find out that it is not they that are abnormal, but the bike they want to buy that may not be the one for them.

Until next time,

Kevin

President

KGS Bikes

Dear Kevin,

I just got my new Campy Super Record group and I need to replace the original brake pads with some designed for carbon rims. What do you do to change pads?

Mark

Hi Mark,

You have brought up a very good point. Bikes now can have rims with an alloy braking surface or one that is carbon. There are two reasons that you really need the right pad and even though you already know that, it is worth mentioning again.

The physicists out there know that the way we stop a bike is to turn kinetic energy into heat. Huh? This is why this is important. The calipers press the pads on the rims and the resulting friction creates heat. A couple of other things happen too.

With alloy rims the pads will collect little bits of metal that get embedded in the brake pad. This scratches the rim, of course, but with an alloy rim it isn’t so bad. This is why it is important to clean the brake pads regularly with a file. That may be another topic.

The pads behave much differently on carbon rims. Alloy rims are a good heat conductor which is why we worry about blowouts in the mountains. The rim gets hot, the tire gets hot, kaboom. Well it is not that dramatic usually, but heat can be a problem. The brake pads for carbon rims don’t have to deal with chunks of alloy rim but do have to deal with the heat. This is why pads for alloy rims melt away quickly with carbon rims.

So back to the task at hand. Brake pads fit into pad holders which are then bolted to the caliper. The fancy bolt on the pad holder has adjustability so the pads can be aligned properly to the rim. Back in the old days pads were not as adjustable and we would actually bend the calipers to get things right!

I like to leave the rear caliper and pads in place on the bike. Once the rear wheel is removed the pads can be removed by pulling them aft. They may be stuck in there so you may have to use pliers to grab the pad and carefully pull it out.

The front pads may be removed the same way, but if they are not easy to remove you need to pull the caliper off the front fork. You then can get to the pads as they will interfere with the fork blades if you leave the caliper on the fork.

Once the pads are off, use Windex to clean the pad holders and get the new pads wet. Windex is a pretty good lubricant that leaves no residue. The new pads are directional! Be careful to put the right pad in the right holder and the left in the left holder.

Once the new pads are installed, reinstall the front caliper and check the alignment. It should still be ok with the rims, however you may need to adjust the cable as the new pads may be so thick that they touch the rim. Start with the cable adjuster on the caliper and if need be, use the caliper set screw to re-tension the cable.

Kevin

Dear Kevin,

I wrote recently about the need for a refit. I still need clarification. My knee hurts at the top of the pedal stroke, right under the patella. Is my saddle too high?

Carlo

Hi Carlo,

Thanks for the question. Since you came to San Antonio for a refitting, I can answer the question and you will know the reason why. To the reader, Carlo got a fitting last year and has been riding quite a bit. As he got stronger his setup changed. Here is how we found out what happened.

The ankle is one of the least discussed parts of bicycle fitting, but how one pedal (toe down or toe up) can make a huge difference in saddle height. One of the fundamental tenets of my fitting system is the stabilization of the ankle so energy is not lost.

Carlo developed stronger ankles over the year of riding and began riding more toe down. When we rechecked him, we had to raise the saddle 20 mm over last year’s setting. The only thing that changed for Carlo was his pedaling action with the ankle. His ankle had become strong enough to overpower his knee angles and as such he got a sore knee.

Here is your quick and dirty saddle height guide. When the front of your knee hurts, the saddle is too low. When the back hurts or your Achilles tendon hurts, the saddle is too high. Higher is better unless it is too high. You can get a higher saddle on a trainer than you can on the road.

What is too high? Your body will tell you. That is what we would find in a fitting session.

Kevin

Kevin Recommends

We only recommend products,  services or companies that we have actually tried or worked with personally. A recommendation, like a reputation, is very important and we do not take this responsibility lightly. The following links are to our friends at the Cooper Aerobics Center in Dallas. Dr. Kenneth Cooper is considered “The Father of Aerobics” and has put together a group of world class companies that have a direct impact on us as cyclists and as professional people:

Cooper Complete – We have arranged for 10% off anything you buy from Cooper Complete if you put “KGS” in the coupon link and then “recalculate”.

Cooper Clinic - The world renowned Cooper Clinic is starting to create medical exams and services aimed at professional adults who ride bicycles.

Cooper Fitness Center – The Cooper Fitness Center has a special strength training introductory program for cyclists.

These links are to our frame builders and other providers that make KGS Bikes the premiere fitting studio and cycling boutique in the world:

Co-Motion Cycles – We’ve long enjoyed a reputation for building tandems that simply handle better.

Guru Bikes – Our approach is based on combining the best of both worlds: cutting edge technology delivered by hand and with an old school attention-to-detail.

Lew Racing – Lew Racing has achieved a following among racing cyclists because of the wheel’s tremendously high strength, low weight and the meticulous attention to engineered performance inherent in its design.

Parlee Cycles – Simply put, PARLEE frames are the best built and best riding carbon fiber frames available today, at any price. They are functional works of art.

Rocket 7 – Since 1999, Rocket7 has been handcrafting cycling shoes in the USA with the finest materials available.

Sem Custom Paint – Dave Sem is the best extreme detail painter in the world.

Serotta – Only Serottas have the extensive engineering of our proprietary Colorado Concept tubing design. It’s the foundation behind the unique ride of each and every Serotta.

Source Endurance – They are teaming with us to provide physiological testing, data analysis, training consultation and long-term coaching. They have two state-of-the art labs, one in Austin and one in San Marcus. We are proud to recommend them and invite you to check them out.

Storck Bicycles – Numerous innovations in frame and component design that are standard in the industry today were developed, patented, and introduced by Storck Bicycle.

Tacx – Home of the Fortius Virtual Reality trainer. This is the trainer component of our “Ultimate Spin Bike”. Tacx also makes many other fine products. KGS Bikes is an Authorized Tacx Testing Center.

Topolino Technology – Our wheels embody this ethic: A fundamental redesign of wheel construction to take advantage of extraordinary materials with amazing properties, yielding a wheelset that performs like no other.

Zinn Cycles – For more than a quarter of a century, Zinn Cycles have been working to make cycling more enjoyable for customers, and that commitment remains at the heart of everything they do.

About KGS Bikes and Kevin

KGS Bikes is known around the world as the premiere bicycle fitting studio and cycling boutique. Kevin Saunders, President, has over 25 years experience in bicycle fitting and high-end bicycles. He also has a broad knowledge of anatomy, structural engineering and industrial design. In addition to fitting services, KGS Bikes sells bicycles from Parlee, Serotta, Zinn, Co-Motion, Storck and Guru. They also feature Lew wheels, custom shoes by Rocket7 and the best available components from around the world. Visit kgsbikes.com for more information, including beautiful photography of the bikes carefully created for their owners.

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