Rasmussen Bike Shop

301 Grand Ave. West Des Moines, IA 50265 • (515) 277-2636
HOURS  ( Out Of Season ): M-F 10:00 - 06:00 • Sat 09:00 - 04:00 • Sun Closed
BG Fit Logo

3D Fit With Data System

$195 ($100 With New Bike)

Tri Bike/Time Trial Fit

$225 (These fits take longer)

Quick Fit / Hourly Fit Rate

$15 Quick Fit / $100 Hourly Rate

BG Fit - Ride Faster, Longer and in Greater Comfort

The foot is the only place where a biomechanical change can take place. The human foot is optimized for walking and running, but is not ideal for the demands of cycling. The forefoot has a natural cant, either varus or valgus, and the longitudinal arch collapses to store and release energy with every step. When a person takes a step forward, the knee falls toward the center of the stride, aligning the quadriceps muscle to absorb the shock, the quads coil to push off for the next step. Meanwhile the foot strikes on the outside edge of the heel, then rolls forward, collapsing the arch. Problems can occur on the bike because the majority of the process described above has little or no use to a cyclist while riding and in some cases can cause injury. 96% of people have a foot with a varus angle, uncorrected the foot collapses against the pedal platform during cycling, which causes the shin bone to rotate and the knee to move repetitively in-and-out towards the top tube, robbing power. To prevent injury and mitigate energy loss the foot needs to be placed in a neutral position throughout the pedal stroke, so the knee is allowed to move in a nearly vertical line.

BG Correction

To correct the natural angulation of the forefoot, BG wedges are placed inside the shoe, to elevate the inside of the foot to prevent collapse. When the knee is aligned, both comfort and performance are improved. Stress is minimized on the knee and power delivery to the pedals feels more balanced and direct. Also a BG footbed (arch support) is also needed to fill the volume under the arch, providing a stable platform to improve power delivery. When pedaling, the footbed prevents the arch from collapsing during the power phase, eliminating common foot discomfort and providing measurable performance gains.

The BG Fit Process

The fit process begins with a basic interview. Where I want to know about injury history, the current uses for your bike, and any future aspirations you may have. After that we will move into the assessment phase, where I will find out what other limitations you may have on the bike. I will look at your foot and knee structure, test your back and hamstring flexibility, your hip flexion, and find out if you have any discrepancies, such as one leg longer than the other. Then I will see what you currently look like on the bike. I will make changes for seat height, fore/aft position, and cleat placement, stem length and rise, and take into account the limiters you may have, and the information I obtained from the assessment.

The BG DATA System

The DATA (Dual Angle Technical Assessment) system uses two cameras, from two different angles to record a rider for assessment. DATA allows me to capture any rider’s body position and pedal stroke on video, perform a quantitative assessment and implement changes to the rider’s position with a level of accuracy otherwise unattainable. DATA allows the rider to see the changes to their position and participate in the fit process at a new level. The industry’s only dual-angle video capture allows me to see the front and side planes concurrently, as shown below. Powerful on-screen drawing tools allow me to illustrate a rider’s ideal position. After a fit session with DATA riders are presented a report that includes their critical measurements.

Specialized Body Geometry

Specialized shoes, gloves, saddles, clothing, and much more were designed by today’s leading mind in bike fitting Dr. Andy Pruitt of the Colorado Center for Sports Medicine. Rasmussen Bike Shop offers all of the Specialized Body Geometry products to custom fit every aspect of your cycling experience.

Aerodynamics

Aerodynamic drag is the biggest force acting against a cyclist under most conditions, and is of primary importance in time trial and triathlon events. For such races, optimizing an athlete's power to drag ratio is essential. During your bike fitting we will address any aerodynamic concerns and capitalize on all available tools to limit your drag and increase your speed.

Sample Analysis Video

Testimonials

The post fit video shows my knees having a nice linear movement throughout the entire pedal stroke. Before the fit, my left knee was moving in a large arc, or an oval. From the short time I was on the trainer in the shop, I felt like I was able to put more power to the pedals, as well as pedal more smoothly.


That said, I feel that the money and time I expended on the fit will be well worth the investment. Adam really took his time during the process and made sure that everything was as ideal as it could be, all without making any unnecessary changes to either me or my bike.


While the results from the fit were noticeable from a comfort perspective, I feel that this fit process took more information about me into account in determining what changes to make.

Steve Fuller | Road & MTB Racer

After 200 miles in California. I found this to be the best fit I've ever had. I instantly felt more power delivered to the cranks.


The bike climbed better than ever and on the flat stages with stiff coastal winds the bike was stable and not twitchy at all and after a couple of long rides I was tired but not sore from fighting the bike all day.


I can't really say why it feels better to ride but I'm sure it's in the detailed analysis Adam did at the shop. The bike is just more fun to ride now and I hope to be spending a lot more time riding it this season.


I wish everyone that rides could experience the difference between a good fit and one that makes the bike feel like its on rails.

Doug Smith | Avid Cyclist

Adam did an excellent job with my fit. He really maximized my position on the bike so I could get the most power, yet still be fresh for the run.


The bike used to be my weak leg, but with Adam's help and some great training, I had the fastest bike split at nationals.

Tanelle Berard | 2009 USA Triathlon Junior Elite National Champion

I was very impressed with Adam's attention to detail. I rode for the first time today on my trainer... I was able to go 30 mins with no pain or hip issues. I know this doesn't sound like much but I wasn't able to do 5 minutes before, I was only limited by being out of shape.


I'll definitely send patients Adam's way and I'll be back when I get a new bike.

Travis Sterling | Board Certified Orthopaedic Clinical Specialist

I just wanted to write and tell you how pleased I am with the bike fitting (BG Fit) you did for me recently. I have been riding in an extremely steep and compact position for a long time because I felt that I would give power otherwise. As we noticed on the video you recorded of my position, this resulted in a compressed spine and a tall upright position - not very aero.


To be honest, I was skeptical that dropping me significantly in the front, extending my bars and moving me back would be sustainable for me given my chronic sacroiliac issues, which was the reason for the "scrunched" position I had been riding.


I am pleased to report that after some test rides I am in fact MORE comfortable and therefore probably more powerful in the new low aero position than when I was riding steep with the seat slammed forward to spare my back. I did a test ride today to compare with something I am familiar with. It consists of 2 x 20 minutes - first at 225 watts and then at 250.


What the data doesn't show is that I was able to stay in the aero position longer without the attendant discomfort, and my position during the second interval, which usually kills my back, was MUCH easier to sustain. Also, I think the corrections you made to my shoes to correct for the leg length discrepancy and collapsing arch made my pedal stroke feel smoother.

Roman Vald | Triathlete