Being that I just got this bike recently I never realized that the while the front turn signal units are also are parking lights, the rear turn signal units are only turn signals. Unlike the fronts they have single filament bulbs. Is this factory correct?
It surprises me that Yamaha would only use combo units on the front ones. From a safety standpoint it would have made sense to have combo units on both front and rear. Unless there is some way to retrofit the rear units to work with dual filament bulbs I plan to replace the rears with some sort of combination unit.
Yes, both my '95 Virago (basically the same bike) and my '03 650 v-star both have three-wire front signals and two-wire rear signals. They are factory correct. The tail light serves as your rear parking light on the 250. Consider yourself lucky with the set up on the 250. My 650 does not even have a "parking light" key position. There's no (stock) way that I know of to run parking lights (only) on it.
The single-filament rear signals are cheap ($15 for the set of two stock lights on ebay), but you may have to get more expensive OEM front indicators if you really want to go two-filament amber on your rears. I wouldn't bother. I've always felt confident even when I only had the single tailight for the rear parking light. Plus, you may have to wire the two-filament amber indicators so that they're on when you ride, to be able to have them on with the key in the parking position. I just personally wouldn't want that. I've got hard bags on the 250 with built-in running/brake lights and I've mounted a nice running/brake light in the middle of the sissy bar plate. They're all red.
I've also added eight extra led running and brake lights, including patterned strobe plate brake lights, to the back of the 650, and, again, they're all red.
They were all extremely inexpensive and with the added chrome bezels they look fantastic.
Combining always-on red and amber in the rear is not standard or expected. Not only could it cause confusion, it just looks like crap.
'03 650 Custom and '95 Cherry 250 Virago:
Kuryakyn Flame Grips. Chrome Covers.
Bullets w' 6.5W 350LM LED Bulbs.
Relocated Rear Signals.
Padded Sissy Bars and Luggage Racks
Lowered. Jardine Rumblers.
Re-Jetted. Corbin Stinger Seat.
Mustang Tank Strap. Large Inspire Bags.
Yamaha OEM Windshield. Purple LEDs.
Chrome Tank and Fender Trim. Eagle Embossed Fork Bag.
Classic Windshield. Mutazu LN Hard Bags w' Lights.