Polaris ACE 150 EFI 2018 Owner's Manual page 70

MAINTENANCE
Drive Chain Lubrication
Lubricate the drive chain with POLARIS chain spray lube or an
approved chain lube at the general lubrication interval specified in the
Periodic Maintenance Chart beginning on page 57. Lubricate more
often under severe use, such as in dirty or wet conditions. See page
102 for the part numbers of POLARIS products.
NOTICE: Washing the drive chain with a high pressure washer or gasoline
can cause premature wear and drive chain failure. Don't use a high
pressure washer or gasoline to clean the drive chain.
Adjusting or operating the vehicle with improper rear drive chain
slack can result in severe damage to the transmission and drive
components. Always make sure the slack is within the stated
specifications.
Drive Chain Slack Adjustment
1. Loosen the upper nut.
2. Turn lower nut clockwise in 1/2-turn
increments, then turn upper nut until
tight. Follow this procedure until
chain is at proper tension. Chain
should have 1/4" deflection.
3. Repeat these steps until chain is
adjusted to desired fit.
68
Upper Nut
Lower Nut