I thought I'd been careful to leave THAT uage of a Dyno 'not maligned'!
Of course, back to back is the BEST you can practically do.
However, how about if it rains in the time between the 'back-to-back' tests? Or a 'front' passes over? Or the Sun goes in and the temp drops by 2 degrees?
Read Nik's comments. If we had stabilised conditions in the dyno room or had twin IDENTICALLY calibrated dynos and you were testing your motor against each other or a refernce motor to see the changes..... or all MANNER of other 'safeguards, they WOULD be a reliable means of comparing motors. However, they are NOT used like that in karting!
The best use would be to check things you can change while RUNNING. E.g., testing the performance with the motor running with 2.5 turns on the high speed jet and rotating that back/forward by 0.5 turns. You'd then be able to see the ACTUAL changes in power and the 'reversability' would be able to PROVE the effectiveness (or not) of the changes.
However, as a method of attaching a 'sheet' to a motor that you are selling/buying and thus 'judging' it, they are worse than HOPELESS as they can be DELIBERATELY used to MISLEAD! How can ANY one tell that the dyno sheet WITH the motor was NOT the dyno sheet from ANOTHER motor?
As I said, NJB is right on this one. After all: he doesn't need MY 'endorsement': those championships of his make MY 'approval' rather 'lame'!
Ian
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