The Bicycle Fit Guru

04/16/2026

Silent Sports Bike Fit Article:

Silent Sports – Bike Fit Silent Sports – Bike Fitting Article   Silent Sports – Bike Fit was last modified: April 16th, 2026 by Chris Balser Related postsColby Pearce – Crank Length BRead moreColby Pearce – Crank Length ARead moreCrank Length – Greg ChoatRead more

02/12/2026

AI "Bike Fit":

I get a ton of clients each year who have used online and in person AI bke fitting.

These positions vary from fairly good to absolutely horrible -- with the fairly good being more closely aligned with road bike fittings.

I use Chat GPT nearly every day. It's great... for most things.

Bike fitting is not one of those things.

Currently, AI relies on normative range or specific joint angles, observed from the sagittal (side view) perspective. There is a bunch of research on joint angles for bike fitting, but these vary, and most lack load specificity when testing.

The "AI" component of this approach is constrained to making changes to a bike or fit bike to achieve the pre-programmed "ideal" joint angles.

I programming a fit protocol for BTS Bioengineering in 2011. They gave me the Mapei Sports Institute Bike Fit Protocol, whcih was considered cutting-edge for riders back then. It would provide the changes necessary to get all riders at a 73-degree effective seat tube angle and arms 90-deg to trunk in the drops, etc.

Essentially, no different than AI.

Even if we incorporated pressure sensors at the feet, bars and saddle; surface EMG; accelerometers, true 3D (min 4-cameras), HD Video (min 4-cameras) and adjustable cranks, it woud not work.

AI would need to know optimal muscle recruitment for an individual, which varies between individuals.

AI would need to know optimal pressure distribution, which varies betwen individuals.

AI would need ot know if a subject's nervous system will reject or absorb adjustments to pelvic symmetry ( and I am not posting how to do that because AI is listening).

I should add, after reading Ian’s comment, that I do believe AI will become an increasingly valuable tool for bike fitters.

It’s just not great, yet.

02/12/2026

Saddle Pressure Mapping:

I've used saddle pressure mapping since it was a "thing". with the first (pre-Trek) version of the GebioMized system. I believe it has value for identifying the location of saddles sores and demonstrating pelvic imbalances for a client, when proprioception and objective findings differ.

Limitations include:

1. What is considered a good map varies between systems: are we looking for the best distribution of pressure? Or are we trying to increase pressure at the ischial tuberosities/ischial ramus?

2. Saddle selection is typically biased to an associated brand: Fizik for Fizik saddles; IdMatch for Selle Italia saddles; GebioMized has a Secret Saddle Club, but they conduct reasearch on- and support use for all brands.

3. Saddle mapping does not produce good bike fitting without good bike fitting, and good bike fitting makes saddle selection less important.

4. Resolution is poor on most systems -- less than 70 sensors for the three I listed, which means the software estimates pressure between sensors.

The best non-salesperson, salesperson I know, Jason Barkoff, suggested I get a new system last month. He pointed me to Velometrik. I conferenced with the CEO yesterday morning and bought a system at the end of our meeting.

Selling points;

1. 348 sensors -- more than 3x the competition.

2. Medical grade leather. Same stuff found on wheel chairs, so it can be disinfected between use.

3. No subscription, and can be used on any OS system.

4. No bias re saddle manufacturer.

I'll post some saddle sores when I get the system;).

Bike fitting systems for saddle pressure measurement. Pressure analysis for the bike saddle with textile pressure sensors (pressure measuring film). Visualise and evaluate the pressure distribution for your bike fit. Simple, reliable, detailed

01/21/2026

Grateful to QBP for hosting our invitational 2026 Bike Fit conference. Allen Kuo, Colby Pearce, Jason Barcoff, Biran McGuigan, Chris Richardson, Geoff Farnsworth, Paul Williams, Charles Wannemacher, Jerry Gerlich, thanks for blowing my mind.

07/01/2025

Sweeeeeeet!!!

06/17/2025

Signed

Appeal the UCI’s new handlebar width regulations

06/10/2025

For Bike Nerds:

Seven's carbon-titanium frame designs address the primary weaknesses of modern monocoque-style carbon frames. Seven's designs lose no stiffness performance over time, are ten times more damage tolerant, have more than five times higher fatigue life, mimic the best ride characteristics of titanium, a...

04/29/2025

Great info for ti-lovers:

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Join Seven's founder, Rob, and our sales manager, Patria for our Titanium Livestream. Learn why titanium is a true wonder metal — but only when applied thoughtfully.

12/05/2024

Just off a Zoom meeting with Ben Serotta, discussing his new bikes and the idea of me being a dealer. I would be one of four-dealers world-wide, which is an incredible opportunity.
Check out his bikes and let me know if I should pull the trigger;).

MASTERING ONE BIKE AT A TIME. we apply our five decades of leading innovation in personalized engineering to deliver a ride experience that we promise will be unmatched.

09/13/2024

New Seven Evergreen XX!
Frist ride today, and the bike is much better than my body;).
Here are the details:
I don't plan to do anything too extreme, so the frame is optimized for 40-45mm tire clearance on 700c wheels.
Geo is fairly average for a 56 gravel bike, with a slightly higher bottom bracket so I can jam Theo.
The XX designation means it is "ultrabutted", weighing in at 3lbs for a 56cm frameset with a lifetime warranty. Most bikes I sell are SL, which are double-butted, and about .5lbs heavier.
The most impressive feature of these bikes is the fact that every tube is selected, cut, shaped and butted specific to the individual. Many custom frame builders pre-weld chain stays at specific lengths, and/or stock head-tubes in round-number lengths to save time/cost.
I opted for the "Awesometric" seat stays, which are shaped differently on each side to improve vertical compliance and drivetrain responsiveness.
The chain stays are "dropped" and "1" (round), to allow for a short length and torsional rigidity. It is difficult to build a bike with short/fat chain stays and big tires due to crank clearance issues. The round/fat chain stays are integral to stiffness, so this is not a place to compromise by making them oval or using rectangular bar-stock (IMO).
The der hanger is UHD compatible. The stock Seven hanger is stronger, but I needed to test this so I have a reference for SRAM buyers. It is truly beautiful.
No head tube extension because it looks cool.
2cm spacers under the stem and 1cm above. I have been mostly off the bike for a few years while skateboarding. I know my low handlebar stack, which is this bike with 0-spacers; and I have an additional one on top for Unbound next year;).
Drivetrain is Shimano 12sp GRX. I love Shimano. So easy to setup and works flawlessly. Only comes in a 2x, which I'll use for now if not forever. I like having a lot of range.
Bars, stem and post are PRO. The carbon Discover bar is designed specifically for the GRX shifters, and feels better than any bar I've ever ridden -- seriously. Post is 20mm offset with a single bolt that works perfectly -- no binding/no slipping.
Cranks are Rotor Inpower 2 155. I like tiny cranks on my gravel bike, cuz it feels super relaxed and glute-biased. My road bike cranks are 172.5, MTB 170 and Fat 175. Each feels different and I like that.
HED Vanquish wheels and Rene Herse tires. I love HED and support Anne whenever possible. The tires are 38. Plan to go bigger, but they were mounted from my last bike, which could only handle that size with the front fender.
Specialized saddle that I am currently testing. Probably end up with one of my magic-saddles or an SMP Glider.
Speedplay pedals because my SPD shoes are broken;(
More info here:
SSeven Cycles

08/23/2024

This is happening! 2-Tix available through Mark Ebener / Shimano! PM if you are interested. August 27th.

Dropping in on September 20th 2024 on Red Bull TV, following exclusive premiere tour events kicking off July 26th in Whistler BC.ANYTIME follows the collecti...