diff --git a/substrate/runtime/src/lib.rs b/substrate/runtime/src/lib.rs
index 10340567..9a534a72 100644
--- a/substrate/runtime/src/lib.rs
+++ b/substrate/runtime/src/lib.rs
@@ -314,12 +314,10 @@ pub type ReportLongevity = <Runtime as pallet_babe::Config>::EpochDuration;
 
 impl babe::Config for Runtime {
   #[cfg(feature = "fast-epoch")]
-  #[allow(clippy::identity_op)]
-  type EpochDuration = ConstU64<{ DAYS / (24 * 60 * 2) }>; // 30 seconds
+  type EpochDuration = ConstU64<{ MINUTES / 2 }>; // 30 seconds
 
   #[cfg(not(feature = "fast-epoch"))]
-  #[allow(clippy::identity_op)]
-  type EpochDuration = ConstU64<{ DAYS }>;
+  type EpochDuration = ConstU64<{ 4 * 7 * DAYS }>;
 
   type ExpectedBlockTime = ConstU64<{ TARGET_BLOCK_TIME * 1000 }>;
   type EpochChangeTrigger = babe::ExternalTrigger;