The speed sensor is located on the rear of the front drive pulley between the top and bottom of the drive belt. It's possible that you could have caused some damage during the lowering process or maybe even during riding. Remove the 3 screws from the front drive cover and see if anything is obviously wrong. The sensor could be misaligned or maybe a broken wire on the sensor.
2014 Vision Nuclear Sunset
XM Radio Module
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1/4 Turn Throttle Ring
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Vic Shop Tweaks: 124 HP / 121 Torque
04 Purple Thunder Kingpin (Sold)