Question: BMX spoke orientation?

noviembre 06, 2026

Question:.

We've been building 20 inch BMX Freestyle wheels for many years, but there's one technical question I've never found a definitive answer to.

We generally use the G-Sport wheel building method, with 36 spokes and a 3-cross pattern. Our leading spokes are laced heads-out and our trailing (driving) spokes heads-in.

I've noticed that experienced wheelbuilders sometimes recommend the opposite method, and I'm curious about the actual engineering behind this.

I'm particularly interested in:

• Which orientation provides better support for the spoke elbow under load?
• Does either method reduce spoke fatigue or improve overall wheel strength and durability?
• Does spoke orientation affect how the wheel handles hard landings, sideways loads and impacts?
• Should the orientation be identical on both sides of the hub?
• Has there ever been any actual testing comparing the two methods?

Our main focus is traditional 20" BMX wheels, both with rim brakes and brakeless. We're primarily interested in the overall structural strength of the wheel rather than braking performance.

However, we occasionally build BMX race wheels with disc brakes. Since braking forces are transmitted through the hub and spokes, would you recommend a different spoke orientation for these wheels, particularly on the disc side?

I'd really appreciate your thoughts, especially if there's any technical research or testing available.

Answer:

Great question. I wish I could generalize but there are too many variables! Increasing the number of variables brings huge increase in complexity to systems. While tensioned wheels share many features, they can be different in ways that strongly affect performance.

To discuss spoke orientation, we enter the strange world of spoke-hub interface with many factors in play:

• Flange—material, hardness, thickness, angle, spoke hole diameter and relief (bevel or radius).
• Spoke—gauge; elbow height, angle, and radius; wire hardness.
• Tension—high or low, loads (magnitude, amplitude, frequency).
• Wheel geometry—spoke angle from flange, crossing or not.

In each of these cases, the possible range is huge. Trying to guess probable outcomes with these variables in play is too much for any serious testing. There’s not enough incentive for a company or university to gear up to this magnitude.

As you have seen in your work, there is fairly insignificant difference. After all, if the differences were predictable and easy to see, there would be more concurrance among experts. Are differences truly insignificant? No, but we need to get on with the builds! So here are points to bear in mind while we agree there are too many variables and insufficient data to generalize:

• More contact between spoke and hub flange improves fatigue life.
• Spoke failure occurs equally in pulling and pushing spokes. It’s more the number of cycles, not their direction.
• Flange spoke holes that more closely match spoke shape improve fatigue life.
• Hub materials that are softer are less associated with spoke failure at the head.
• Most lab wheel testing is not real-world. Real world wheels see many types of loading.
• Most wheels fail from trauma, not fatigue. Those that last long enough to fatigue are a biased group.
• Wire quality most affects spoke longevity.
• Stress relieving (more than pre-stressing) is associated with improved fatigue life.
• Most BMX wheels are overbuilt so results are scarce.
• We have the technology to gather and process data but testing is expensive!
• The most dramatic environments are competition and accidents. With the latter, forces can be overwhelming and arbitrary. With competition, human factors are hugely important and events are limited. How many race days are there? Not enough!
• We and Mavic ('80's–'90's) shared a lot of information. For many years, our (US Nat'l Team) best idea was pulling spokes with elbows outside. Mavic preferred the opposite. We both had great results. I think it didn’t matter. The same seems true for whether each flange should mirror or be opposite the other side.

All this gives you, the builder, a ton of freedom to employ unusual patterns, make wheels distinctive, confuse your competitors, and express your mood! All good, yes?

TAKEAWAYS

• BMX wheel design can be practical and budget conscious. But better builders these days are at the cutting edges of tensioned wheel theory.
• Most spoke pattern variations are unlikely to have a significant effect on strength.
• A good guiding principle: do your best with each detail and keep track of outcomes.

What do you all think?

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