If the bulb is in working order and all the other indicators are ok, that just leaves the indicator unit itself and the wiring to it, sorry do not know if a Zip has two wires (one is the return earth wire)or if the unit is earthed to the bike, make sure the bulb contact and the spring loaded bulb holder are clean & bright then remove & check behind the spring loaded bulb holder, has been known the wire breaking off these, if so solder back on, re-assemble & spray a bit of wd40 on it & check. Can't be much else but a broken or shorted wire back from the indicator to the bike if all this doesn't cure it!
Ted
May 2011
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