Street Dyno: How Power Estimation From Ride Recordings Works
Street Dyno estimates horsepower and torque curves from your live ride recordings. Instead of booking a chassis dyno, you record a ride: the app combines accelerometer data, GPS speed, and wideband O2 readings from the log and calculates power and torque curves from the pull. No strapping the bike down, no shop appointment — the road is the test cell.
The logic is straightforward physics. Vehicle speed over time gives acceleration; acceleration against the known mass of bike and rider gives force at the contact patch; force and speed give power. The wideband data is what makes the result trustworthy as a tuning tool rather than a party trick: a pull made at a known-safe, on-target mixture means the resulting curve reflects the tune you actually intend to keep, not a lean fluke that overheated the engine for a momentary number.
To get clean runs: fully warm the engine, pick a safe and legal road, and make a smooth full-throttle pull through as much of the rev range as conditions allow. Repeat in the same gear, same road, same conditions. Consistency between runs matters far more than any single run, because small differences in wind, grade, and rider position all show up in the estimate.
The best use of Street Dyno is comparative. Record a baseline on your current calibration, make one change, flash, and run the same loop again. The before/after comparison view and CSV export exist exactly for this. Treat the absolute number as an estimate; treat the delta between two consistent runs as real information about what your change did.
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A tuning note on why the wideband channel is not optional decoration: an air-cooled V-twin makes its best sustained power at roughly 12.5–13.2:1 AFR under full load (community consensus, not a factory figure). A pull that runs leaner than that can produce a briefly higher number while carrying heat into the pistons. If the wideband says a pull ran at 14:1 or leaner at full throttle, stop and add fuel before the next one — and do not compare that run against healthy ones as if they were equal.
Logistics: logs are stored on your vehicle profile in the app, session bookmarks let you mark the pulls that count, and everything exports to CSV if you want to analyze the runs in Excel, MATLAB, or your tool of choice. Baseline first, one change at a time, same route — that discipline is what turns Street Dyno from a number into a tuning instrument.
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