diff --git a/polkadot/runtime/kusama/src/lib.rs b/polkadot/runtime/kusama/src/lib.rs
index 40478fe0d8..daa19477b5 100644
--- a/polkadot/runtime/kusama/src/lib.rs
+++ b/polkadot/runtime/kusama/src/lib.rs
@@ -883,6 +883,17 @@ impl proxy::Trait for Runtime {
 	type MaxProxies = MaxProxies;
 }
 
+pub struct CustomOnRuntimeUpgrade;
+	impl frame_support::traits::OnRuntimeUpgrade for CustomOnRuntimeUpgrade {
+	fn on_runtime_upgrade() -> frame_support::weights::Weight {
+		if scheduler::Module::<Runtime>::migrate_v1_to_t2() {
+			<Runtime as system::Trait>::MaximumBlockWeight::get()
+		} else {
+			<Runtime as system::Trait>::DbWeight::get().reads(1)
+		}
+	}
+}
+
 construct_runtime! {
 	pub enum Runtime where
 		Block = Block,
@@ -984,7 +995,14 @@ pub type UncheckedExtrinsic = generic::UncheckedExtrinsic<Address, Call, Signatu
 /// Extrinsic type that has already been checked.
 pub type CheckedExtrinsic = generic::CheckedExtrinsic<AccountId, Nonce, Call>;
 /// Executive: handles dispatch to the various modules.
-pub type Executive = executive::Executive<Runtime, Block, system::ChainContext<Runtime>, Runtime, AllModules>;
+pub type Executive = executive::Executive<
+	Runtime,
+	Block,
+	system::ChainContext<Runtime>,
+	Runtime,
+	AllModules,
+	CustomOnRuntimeUpgrade
+>;
 /// The payload being signed in the transactions.
 pub type SignedPayload = generic::SignedPayload<Call, SignedExtra>;
 
diff --git a/polkadot/runtime/polkadot/src/lib.rs b/polkadot/runtime/polkadot/src/lib.rs
index 599912ea83..b21ad3bdbc 100644
--- a/polkadot/runtime/polkadot/src/lib.rs
+++ b/polkadot/runtime/polkadot/src/lib.rs
@@ -865,6 +865,17 @@ impl proxy::Trait for Runtime {
 	type MaxProxies = MaxProxies;
 }
 
+pub struct CustomOnRuntimeUpgrade;
+	impl frame_support::traits::OnRuntimeUpgrade for CustomOnRuntimeUpgrade {
+	fn on_runtime_upgrade() -> frame_support::weights::Weight {
+		if scheduler::Module::<Runtime>::migrate_v1_to_t2() {
+			<Runtime as system::Trait>::MaximumBlockWeight::get()
+		} else {
+			<Runtime as system::Trait>::DbWeight::get().reads(1)
+		}
+	}
+}
+
 construct_runtime! {
 	pub enum Runtime where
 		Block = Block,
@@ -962,7 +973,14 @@ pub type UncheckedExtrinsic = generic::UncheckedExtrinsic<Address, Call, Signatu
 /// Extrinsic type that has already been checked.
 pub type CheckedExtrinsic = generic::CheckedExtrinsic<AccountId, Nonce, Call>;
 /// Executive: handles dispatch to the various modules.
-pub type Executive = executive::Executive<Runtime, Block, system::ChainContext<Runtime>, Runtime, AllModules>;
+pub type Executive = executive::Executive<
+	Runtime,
+	Block,
+	system::ChainContext<Runtime>,
+	Runtime,
+	AllModules,
+	CustomOnRuntimeUpgrade
+>;
 /// The payload being signed in transactions.
 pub type SignedPayload = generic::SignedPayload<Call, SignedExtra>;