Getting a Retul Bike Fit Done

Getting a Retul Bike Fit Done

It has been a while since I’ve blogged here on BicycleTips and it is time to get started again! Less than 2 months remain until I ride the 100-mile distance at the Dirty Kanza #DK100 in the hills of Kansas, so it is time to dust off the bike, dust off the keyboard, and get to stroking the pedals and the keys.

So I’m riding in the #DK, how did that happen? Well, earlier this year, a couple of us at the gym decided we were going to enter the lottery. When entering the lottery for the Dirty Kanza, you have the option of entering by yourself or putting down a TEAM name (up to 4 riders, I think). If you put down a team name and someone from your team gets selected, everyone gets in. I don’t believe that I was selected individually for the ride, but the other guy who ended up signing up, we’ll call him Steve, was selected, and thus I was pulled in as well!

I’m not going to get into “what” the Dirty Kanza is, other than to say it is a gravel ride in the Flint Hills of Kansas and is known as a tough event (race). We’ll be riding the 100-mile distance, which is unsupported and has one supply zone in the middle (50 miles) where you can have someone resupply you with food/drink/gear.

In prep for the DK, I decided it was time to try to get my Niner RLT gravel bike sized a little more appropriately. When we did the Katy Trail ride in 2017, I didn’t feel like I was as efficient as I should/could be on the bike, and I didn’t want to relive some of that pain, so I booked a bike fitting at Trailhead Bicycles in Ellisville, MO. The fitting at Trailhead uses the Retul Bike Fit system.

This was my first time getting fitted on a bike, so I wasn’t 100% sure what to expect. Prior to the fitting I was told to bring:

  • Shoes/Cleats/Pedals
  • Kit (shorts/shirt) to ride in
  • Bike
  • Bottle of water
  • Snack

I booked the appointment for 4pm and arrived shortly before that to try on a new pair of shoes that I had ordered (figured it was time to upgrade my 10-year-old MTB shoes I’ve been using). Once I tried the shoes on, we began the process for the Retul Fit.


The first step in the process was an interview. The bike fitter (technician?) Harrison asked me a series of questions. Height, Weight, DOB, any prior injuries, pain areas, average number/length of rides, etc. This is pretty simple, not sure how useful it is, though you might want to think of issues you have while riding before your fitting. I thought of a couple of things post-interview that I spoke about, would probably have been more helpful if I had them written down ahead of time.

Sit Bones and Foot Arch

After the interview, the next thing I went through was checking my sit bones. If you’re new to riding, your saddle (seat) is one of the most important things about your bike, being comfortable on long rides. It isn’t about having the most padding, honestly, most good saddles have minimal padding. To measure the sit bones, I sat down on a tablet-like device that measured the distance between my sit bones, the points that typically touch the seat on your ride. My measurement put me about 155mm, while the saddle on my bike measured around 143mm. I have often found that I sat crooked on a bike, I think we finally figured out why. With the measurement done, we picked out a new saddle for me, the Specialized Power Expert in the 155mm width.

In addition to the saddle fitting, before near the bike, Harrison had me sit and put my feet on a touch-sensitive pad that measured the arch on my feet. Sitting, I had a fairly high arch. He then had me stand and measure how much my arch collapsed, to which we were both surprised that my arch didn’t collapse at all while standing (I’m a big guy and have had some foot pain in the past, so I assumed it was an arch issue). This told us that I might benefit from some arch support to help keep my high arch while riding, but they didn’t have any insoles in my size, so they had to order those.


Specialized Expert XC Mountain Bike Shoes

From there, I tried on my “new” shoes that I had ordered a few days before my fitting. I ordered the Specialized Expert XC Mountain Bike Shoes in an understated color. The shoes fit great, so I was then measured to see where the cleats should be mounted. The position decided was fully to the rear of the adjustment range. I have never had my cleats this far back, but the fitting was being done for a purpose, so I went with that decision.


From there, we went through some flexibility movements and measurements. I believe my mobility was pretty good for a guy my size (6’4” 250lbs), primarily due to my work in the gym for the past year. I won’t get into all the specific measurements and movements, but angles were measured at my hips, knees, and even flexibility in my feet/ankle.

On the Bike

After going through the various steps, it was time to get outfitted for the bike. I was decked out in my kit already, but before getting on the bike, I needed to be outfitted in velcro, for all of the sensors. Sensors were placed on both sides of my body, on my shoe, ankle, knee, hip, shoulder, elbow, and wrist. The sensors are part of the Retul fit system, which consists of a device that looks like a very large Microsoft Kinect, that records the data from the sensors and the various movements the body makes while riding. Once I was fitted with sensors, I got on the bike and rode a bit to get warmed up so that the system could record my initial data.

My bike was mounted to a Kinetic trainer, all of which sat on a platform that could be rotated around 360 degrees, locking every 180, so that it was easy to transition between left and right side recording.

One thing to prepare yourself for while doing a fitting is riding, you’ll get quite a bit of seat time. There is plenty of “break” in between, but you’ll ride more than you might think ahead of time.


Once we got some basic riding in, we started by working on my position on the bike by swapping my current saddle out with the new one from Specialized. In doing so, the saddle was moved back a bit, trying to bring my knee back towards the pedal more, instead of it being out in front of my foot/pedal at the measurement point. My saddle height was also adjusted to get the optimum power out of the position as well. We started off with my seat level but ultimately brought the nose down a bit to see if that helps with some numbness I have had previously on long rides.

Hoods, Stem, and Bar Height

After working on the saddle and the rear of the bike, we moved forward to the hoods. Immediately, we raised the hood angle up, bringing them more upright, without adjusting the actual bars themselves. While working on the front of the bike, Harrison put the bars into an adjustable stem, which allowed us to move them forward and back easily for fitment purposes. The stem on my Niner RLT was 90mm, and he thought that might be too long based on the measurements we were taking, so we shifted to an 80mm adjustment and that brought me in line with the desired measurements. Trailhead didn’t have an 80mm stem that would work on the racks, so they ended up taking one off another bike, not the ideal setup, but it got us through the fitment. I may order a lighter stem here soon, but we’ll see if I want to drop more cash.

The last adjustment we ended up making was the bar height; we took one spacer out, lowering the height just a bit.


After all the adjustments were made, the shop owner gave the bike a once-over, rewrapped my bars (due to the hood adjustments), and then they sent me on my way. I was instructed to take the bike out on 5 or 6 rides and then have a follow-up fitment. I stopped by the shop today to schedule that follow-up for next Tuesday. The fitment itself took just over three hours. It is pricey, and even more so when you start adding in equipment (shoes, saddle, stem), but I believe it is worth it for a serious rider (something I want to be).

I’ve been on the bike 6 times for about 120 miles, and overall, I am very pleased with the fitment. I think the biggest improvement is the new saddle, it is so darn comfortable, though the longest ride I’ve done is only 30 miles. I’m hoping to get out for 40 or 50 miles this weekend before the follow-up. I don’t find that I am super more efficient on my gravel bike now; it is still slower on the road than my road bike, but I am comfortable now, and that should help to minimize pain and discomfort at the Dirty Kanza 100 on June 1st, 2019.

About the Author:

Chris Hammond
Founder of, an avid computer geek, photographer, and amateur bicycle rider. Read more about Chris Hammond.