diff --git a/Makefile b/Makefile
index acba223..a9c9f30 100644
--- a/Makefile
+++ b/Makefile
@@ -51,7 +51,7 @@ after-test:
 	[ "$(CI)" != "true" ] || codecov
 
 install-style: install-docs
-	pip install flake8 flake8-import-order flake8-bugbear
+	pip install flake8 flake8-import-order flake8-bugbear>=17.3.0
 	
 style:
 	flake8
diff --git a/setup.cfg b/setup.cfg
index 2bda4a6..85e7d24 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -6,8 +6,7 @@ norecursedirs = tests/storage/servers/*
 
 [flake8]
 # E731: Use a def instead of lambda expr
-# B902: first method param should be self
-ignore = E731, B902
+ignore = E731
 select = C,E,F,W,B,B9
 exclude = tests/storage/servers/*, build/
 application-package-names = tests,vdirsyncer