If you put regular bulbs back into the system you have increased the resistance... let me back up. Most turn signal flashers use a bi-metallic switch (bms) to open and close the circuit. The bms heats up based on amperage draw which is related to the bulbs in the circuit. LED's draw very little amperage. So when an incandescent light bulb is replaced with led often times the bms doesn't get hot enough to break contact. One of the cures is to install a resister pack into the circuit so the amperage draw is the same as it was with incandescent bulbs.
So, when you put incandescent bulbs back into the system after this mod, you now have twice the amperage draw you had before, the bms heats up twice as fast and cycles accordingly. In all of my custom bikes I use led's because of the lower amperage draw. This makes life easier for early Honda alternators which weren't all that robust. I use a flasher unit designed for semi Trucks. They are a 2 prong, 1 wire unit. The two prongs go into the normal wiring and the wire is a ground. There is a little motor and cam that spins and opens/closes the circuit. It doesn't have a bms so it works whether you have 2 lights, 18 lights or leds.
I hope this helps.
Eric
