These heaters are designed for standard hollow steel handlebars of 22mm(7/8") outside diameter.
The length from end to center of the handlebars should not exceed 500mm(20").

For 1 inch (25mm) bars click here

Center punch and drill 2 x 3mm (1/8") pilot holes. Centers 25mm(1") apart.
Re-drill to 9.5mm (3/8").

1: Cover fuel tank, front wheel and headlight.
2: Drill holes as shown in the diagram. 3: Cut flaps as shown in the grip ends. Remove the plastic part of the throttle assembly covering handlebar end. 4: Terminals are held by the sleeving to help this procedure.
5: Push heaters into position as shown. Fit switch; do not operate with top removed.