if they are LED indicators you need to fit resistors inline to the positive feed to the indicator not the earth wire, this stops overload, as the bike has a 12 volt system and sends a certain amount of current to the indicator as its LED it uses far less than is being sent which results in an overload, this will cause it to flash far too fast or be constantly on, many LED replacement indicators have resistors built into them but the cheap Chinese ones don't, I fitted LED indicators to my Honda TL as one had a broken stem,after fitting the LED indicators from ebay (£12) one side worked great but on the other side one indicator was on all the time and the other one flashed far too fast, I thought I might have wired them in the worg way round, positive instead of negative etc but I hadn't so I switched back to 12 volt bulb indiactors and the problem was solved, the thougth of soldering in four resistors and weather sealing them didint appeal to me so it was back to ebay for some 12 volt bulb indicators (£25)
Does anyone want four Chinese made none resistor-type indicators, free to good home l0l. . . they look great but don't work, some new bikes with LED indicators have the resistor fitted inline and some have the resistor fitted inside the indicator so fitting replacements is a bit hit and miss, two resistors can lower the current too much so the light is dim, to be honest the 12-volt bulb indicators are brighter and when they do blow if they ever do are a lot easier to change, LED bulbs get dimmer with time conventional bulbs don't,