MotoGP has been a very competitive sport thanks to stringent rules & regulations and ultra high reliability standards by the teams. Reliability has been a very important part of the sport as the number of engines a team is supposed to use is fixed (7 to be precise) and their use across 18 rounds of a championship tests the limits of each and every component that's present inside the sealed engine of a MotoGP fire breather. The 2016 Italian GP served to be a forgettable weekend for Valentino Rossi, his bike encountering a very rare engine failure in the race. Rewinding to the last lap of the warm-up session, another Yamaha engine breathed her last when Jorge Lorenzo encountered the same problem. Initial reports claimed there was a faulty component in the YZR-M1's metallurgical masterpiece, but thorough analysis says otherwise.
The Mugello circuit has a very long straight (1.1 kilometers) where bikes attain a maximum speed north of 340 km/h. The engines have to be redlined for a significant amount of time before she gets some breathing space down in the braking zone of San Donato.
Yamaha's Kouji Tsuya explains how a minor electronics glitch caused two engines to die on the same day.
After the technical problems in Mugello the two defective engines were returned to YMC for investigation. Following our detailed investigation of the engines, telemetry data and related systems we found the cause of the failures. The failures were caused by an electronic issue related to the rev limiter which ultimately resulted in valve and piston damage. The cause for both Jorge‘s and Valentino‘s engine failures was the same. To be clear, there was neither an engine component nor a structural failure, it was purely an electronic control issue.
As the electronics package is changed from this season, all teams adopting the same Magneti Marelli suite meant that the redline settings used on last year's package didn't work perfectly or as intended on this year's more basic and simplified version. Thus the engine was let to over-rev by a slight margin which caused the failures.
These failures meant both Valentino Rossi and Jorge Lorenzo will have one engine withdrawn from their 7 engines for the season and both shall use fresh engines for this weekend's Catalan GP.
By: Suraj