If Sky Rider's suggestion checks out to be ok, then you can solve your problem in one of 2 ways:
a) you can install a dual-load equalizer, readily available at someplace like J&P Cycles (this will solve your problem, but this option defeats the true purpose of LEDs, since the bike's charging system has to work just as hard with an equalizer) or...
b) you can install a digital flasher, which flashes the signals at a rate that is not load-dependent.
A good example of a digital flasher that is a true "drop-in" replacement fit for the VN750 is at:
The problem with the digital flasher is...if you turn your bike's hazard flashers on, and all your turn signals are stock, you will immediately fry the flasher's circuitry. Even just using the OEM signals on one side of the bike will push this flasher's circuitry to near (or at) its limits.
For a digital flasher to be a worthwhile option, most of your signal lights really should be LEDs.
Most digital flashers can't handle much more than a few amps (if that), otherwise their internals will be cooked.
Over the next few weeks, I plan to remove ALL
of my factory turn signals, and replace them with LEDs.
The factory signal housings leak, rust, and (if left on the bike long enough) eventually sag.
So...in the true spirit of cruiser customization, I've decided to do away with them--completely.
Stay tuned....this should be a fun ride....