We sell these accessories to riders for protection from wet and cold weather. However, we must warn them against the
danger of injuring their engines if they ride their motorcycles too fast when equipped with the above-mentioned
accessories, particularly the fabric splash shields or metal leg shields.
The passage of air around the cylinder and cylinder head cooling fins is restricted to the extent that it is similar to operating an automobile without a fan belt or without water in the radiator; that is, the cylinder and cylinder head temperature will rise much higher than it does under normal operating conditions.
The rolling resistance built up by a head wind against the large wind shield causes the engine to labor abnormally,
which also contributes to this over-heating condition.
The first warning of insufficient cooling is the extraordinary heat radiating from the right side of the engine.
The second warning is “pinging”, pre-ignition of the spark plugs, which causes the engine to slow down.
THE FOLLOWING PRECAUTIONS SHOULD BE TAKEN TO PREVENT SERIOUS DAMAGE TO THE ENGINE:
- Do not ride mile after mile over 50 m.p.h. (solo) 45 m.p.h. (sidecar) when the temperature is above 40°. ( If it is necessary to ride above these speeds, we suggest that you remove the right leg shield.)
- Back off the throttle when you feel the heat on the right side of the engine or when you hear the engine “ping”. (Cruise a.t a speed where the engine doesn’t ping”.)