2007-2009 Suzuki LTZ90 factory service manual, Page 43Get this manual
PERIODIC MAINTENANCE
CLUTCH LOCK-UP INSPECTION
Perform this inspection to determine if the clutch is engaging fully and not slipping Connect multi-circuit tester onto the spark plug high-tension code Start the engine Apply the front and rear brakes as firmly as possible Fully open the throttle for brief period and note the maximum engine speed sustained during the test cycleLock-up speed: 400 000 rmin