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I know that the best way to shift and to also create clutch longevity is to shift at the point where the bike will enter the next gear at an RPM equal to the engine's torque peak. So... for those who have dyno'd their bikes, as they optimize shift points for better readings - do you have any input on this for normal street riding... or should I be shifting every gear around 9k or 13k?
 

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When the tech ran the bike up to the rev limiter he did not shift. Rather he ran it up once in each gear. He shifted up to the higher gears at low RPMs before running it up in that gear.

That brings up some good questions though: What gear was the bike in for the chart he gave me? What gear gives the best performance on the dyno and how much difference is there between gears? Does changing the gear ratio affect the dyno run vs. stock gearing? Curious minds want to know.
 

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eprior said:
Does changing the gear ratio affect the dyno run vs. stock gearing? Curious minds want to know.
I bet it does. There was an article in a recent motorcycle magazine where they looked at the difference in dyno results just from using different tires. Change nothing on the bike or setup other than tires. Surprising variance.
 

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I have nevered done a dyno test so I am missing the experience and thrill.

IMHO, dyno'ing in lower gear will give higher readings than in a higher gear. In low gear, the rear wheel will reach a lower maximum angular speed. Any spinning wheel has rotation inertia to overcome by the engine. So a low-gear test will be less incumbered by the rear wheel inertia than otherwise.
 

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In a car, you put the car in it's 1:1 ratio, usually 4th in a standard and 3rd in an automatic, and run it to the rev limiter. I don't know about a bike, the FZ6 doesn't even have a true 1:1 ratio.
 

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I think a dyno is supposed to be measuring power/torque numbers for the engine, but indirectly. The measurement point is through the tranny and rubber, which introduces losses. But I'd say that's a good thing (you get a measurement that accounts for real-world losses) and I suppose those losses won't vary (much) with the specific gear you are in.

If the revs are changed gradually enough over the range, then skeleton's point is addressed, but still the graph can't be plotted without adjusting for the gear ratios. So they must dial in those numbers for each gear tested and (I guess) they average the results, which would average the error and tend to produce a more accurate result -- iff they got the ratios right.

This is all speculation on my part, I know nothing about dynos. I'm probably just showing my ignorance... :D
 
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