I chatted with AI regarding the efficiency number that are on the internet and are widely quoted.
"No peer-reviewed or independent laboratory studies specifically testing motorcycle belt and chain drive efficiency under controlled conditions were found.
The most frequently cited data comes from a 2012 Friction Facts laboratory test, but it was conducted on bicycles, not motorcycles"
Test here;
https://www.cyclingabout.com/wp-content/uploads/2015/09/Gates-Carbon-Belt-Drive-efficiency-vs-traditional-single-Friction-Facts.pdfIn short.
Gates Carbon Drive vs. Chain Efficiency Test
Chain loss: 2.92 watts (average)
Belt loss: 3.93 watts (average)
Tested at 250W load, 95 RPM, with belt preloaded to 85 lb (per Gates guidelines)
While this test is rigorous and repeatable, it does not simulate motorcycle power levels (typically 50–150+ hp vs. ~0.3 hp in the test). The mechanical principles (friction, hysteresis, preload) are relevant, but scaling to higher torque and speed may alter efficiency outcomes.
Some motorcycle-specific claims (e.g., 97–99% efficiency for both systems) appear in manufacturer-backed or trade publications, such as a 2025 test by Gates and Universal Transmissions, but full methodology and raw data are not publicly available.