These lights measure 3 3/4" in diameter

Part #8301 CHR

Direct replacement for Triumph and Norton OEM # 61-6019

mount them on both sides of your bike or just one

Triumph Layshaft Needle Bearing - Closed Triumph Motorcycle OEM #57-1606 Vendor_Mid-USA Motorcycle Parts These lights measure 3 3/4"This is a closed end layshaft needle bearing for 650cc, 4 speed pre unit and unit construction Triumph motorcycles. Triumph OEM part #57 1606. This is a Koyo brand bearing, made in the USA. Also available, the Triumph Layshaft Needle Bearing Driver Tool from Lowbrow Customs, which makes installing your transmission needle bearings a breeze!