TyreCop Pro +

The Core Case: External vs. Internal Temperature

An external valve-mounted sensor does not measure true tyre-air temperature. Its readings are influenced by multiple external factors, including internal air temperature, ambient conditions, radiant heat from nearby components, and airflow around the wheel assembly.

A rim-mounted sensor, by contrast, functions as a genuine internal probe. The brass base seals into a dedicated NPT threaded hole, and a 28cm flexible cable carries the actual sensing head deep into the tyre cavity, away from other sources of heat.

This is not an incremental improvement — it is a fundamentally different measurement method. External sensors report temperature near the wheel; the rim-mounted sensor reports the temperature of the air the tyre is actually operating in, enabling the TyreCOP Pro+ to calculate and communicate the precise pressure correction required. No assumptions. No compensation curves. Just accurate pressure maintenance.

Why It Matters in Practice

• Location bias skews valve-mounted readings — air near the rim edge is affected by rim material conductivity, wheel rotation, and proximity to the brake assembly, especially under braking.
• The 28cm cable reaches representative cavity air, sampling a location far less influenced by any single localised heat source.
• Accuracy compounds downstream — temperature data feeds pressure compensation and tyre strategy, so a biased input produces a biased result everywhere it's used.
• The seal is engineered for this, not a workaround — the ¾″ brass base is a threaded, sealing fitting purpose-built for the hole, not an improvised modification.

Addressing “But You're Drilling a Hole”

• It's a designed modification, not damage — a ¾″ NPT threaded hole with a proper brass seal is a controlled, standard operation, the same category as the valve hole itself, just relocated and sized for the sensor.
• One-time cost vs. ongoing accuracy — the hole is drilled once; the benefit applies every session, every heat cycle, for the life of the wheel.
• It removes load from the valve — valve-mounted sensors add mass and leverage at a known stress point, especially at speed. A separate sealed port takes that risk away.
• It's serviceable — if ever required, the port can be plugged with a blanking base, and it doesn't compromise the integrity of the wheel any more than the existing valve hole does.
• Sensor replacement, without the teardown. Where other internally-mounted sensors force you to remove the wheel unit, strip the tyre, fit the replacement, and rebuild the whole assembly, a rim-mounted sensor can typically be swapped on the machine: support the load, deflate, unscrew the old sensor, fit the new one, re-inflate. Even in the rare case the wheel unit has to come off, the tyre stays fully assembled throughout.
• When changing tyres, the same sensor can be refitted in the new tyre.

If your data is only as good as where you measure it, the hole is the cost of a measurement that's actually true.