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What's my revs?
Posted 19 September 2017 - 07:40 AM
If I reach 80 kph in second gear on 175.70.13 tyres nearly new tread....am I really doing the near 8000 rpm my tacho tells me?
Posted 19 September 2017 - 10:22 AM
Posted 19 September 2017 - 11:30 AM
According to Wikipedia, second gear is 1.95:1. At 3.7: 1 final drive, total ratio from the engine to wheels is 7.215:1
175/70-R13 tires are supposed to be about 1807 mm around.
80 km/h is 1333.3 m/minute
So I get 1333.3/1.807*7.215 = 5324 RPM. Not 8000.
If it is a 3.9:1 final drive, then the RPM is 5612 RPM. That is a bit closer to a redline marked at 6000 RPM. Could the tach read 7% high? If so, this may be what you are seeing.
Posted 19 September 2017 - 05:28 PM
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