[DeTomaso] NPC but a question about LED blinker circuits

[Christopher Kimball]

I have a Yamaha V-Max, and like most motorcycles, it has a lot of power--except where the battery is concerned.
To ease the strain on the battery, I changed the rear taillight and brake light bulbs for LEDs, and the front running/turn-signal lights.  With the rear turn-signal bulbs remaining stock, the left and right turn-signals work well, although they blink faster than normal.  I remembered when I replaced all the bulbs in the Pantera with LEDs I had to use a special turn-signal relay module, so I wasn't surprised that when I tried replacing the rear blinker bulbs on the V-Max with LEDs, the turn signal, when placed in either right or left-turn mode, simply causes all the turn signals to blink in unison.
Does anyone have a suggestion of an easy fix for this (and by easy I mean cheap...!)
Thanks,
Chris