I have a 97 Softail Costum with a turn signal problem. I can turn the igniton on activate the left turn signal it blinks fine. I can start the bike and it blinks fine as long as it is idling. If I rev the engine just a little the signal burns bright and stops blinking.When I release the throttle it starts bling again.

HELP.
I have already replaced the turn signal module and the new one did not work so I put the old one back in.

 

sounds like a grounding issue or a voltage regulator problem. make sure your battery ground is firmly tightened, and also make sure it's tight at the starter. i dont' know how to test the voltage regulator off the top of my head but they're cheap and easy to replace.

 

That is a voltage regulator or battery problem. When you run up the engine the alternator puts out more voltage. It is up to the regulator to make it even at all times. If the battery is going bad will not have a even charge and that also can cause a problem. Something to look into.