Indicator bulbs: handy tips

Q. I wonder what the minimum wattage is for bike indicators, if there is one?

• Save cash on motorcycle lighting

I have bought some new winkers for my Kawasaki 400 grey import and they’re 10 watts, which I don’t think is strong enough and may be illegal?
Les Coalwell, Cheshunt
 
A. European Directives cover the use of lights on motor vehicles and they don’t stipulate minimum wattage as that isn’t really a good guide to light emitted, which is down to reflector design.

For example rear brake light reflectors on cars are generally silver-painted, while high intensity fog lights use chromed reflectors.

Instead those Directives measure light intensity in candela and stipulate minimum values dependant on position relative to a brighter light source like the headlight. Indicators can be between 90-700 candela (cd) for the fronts, 50-200cd for rears.

If there’s at least 75mm separation the minimum value is 90 candela, if it’s down to 40mm it’s 175 cd, and less than 20mm they need to be at least 250cd.

The safest bet is to look for components that are E-marked as that shows they’ve been tested.

The front indicator lens should have “11”, while a rear lens should show a “12”. Beware of cheap copies circulating on eBay.