The Bicycle Fit Guru

Silent Sports Bike Fit Article:

Silent Sports – Bike Fit – BicycleFitGuru.com 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

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.

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 | Saddle Pressure Mapping, Pressure Sensors 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

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.

Sweeeeeeet!!!

Signed

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