| Re: 09 xp track speed
If you start to gear down say from your 21 to a 19 you'll start to probably find a black ring apparent in the primary.
What is happening is with the lower gear ratio, under full throttle the belt will be lower in the secondary. The roller in the secondary will be at a larger helix angle (reverse 43/47) so then there will be even less belt clamp than a lower helix angle.
From experiences the rpms will recover quickly yet may fluctuate but the belt will slip in the secondary - the primary will start to have a buildup of black ring(s).
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