Yamaha V-Star 650 steering "snaps" into place when doing slow manoeuvr

anyone have that problem with a Yamaha V-Star 650?  There is no sound, just when I get to a certain point in the turning radius when doing a slow u-turn, etc, the front end "snaps" around and both my husband and myself have dumped the bike. My hubby is concerned enough that he wants me to get another bike as his HD cruiser is as smooth as butter in slow manoeurves.  

I know of two different problems you could be talking about here.

First, if you mean after turning the forks past a certain point, they want to continue turning all the way over against the steering lock, that is a matter of balancing the lean angle against the steering angle. When holding the bike straight, as you turn the forks, the contact patch shifts sideways away from the center of the bike's weight. The farther it gets out from under the center of the weight, the more leverage that weight has to force the steering past where you want it to be. When you lean the bike over to keep that contact patch centered under the bike's weight, the weight never gets any leverage at all and the bike stays responsive and steers easily. The farther you turn the forks, the farther you have to lean the bike to keep the steering neutral. This is a matter of practice, at leaning the bike to extreme angles during slow maneuvering.

The second possibility is a damaged steering head bearing. Typically, as the bearings wear, the bearing races develope indentations where the balls set most of the time while riding, due to vibration. Unless the steering head has been tightened too much, this usually doesn't happen until the bike gets well beyond 50,000 miles on it. When it does happen, you feel the steering click into position around the straight ahead angle and it takes more effort to make slight steering inputs as the bearing resists turning the forks away from that position.

regards,
Joe  

Depending on the actual number of balls in your steering head bearings, with a badly worn bearing, you may or may not find other detent points as you turn the forks towards the locks. Block up the bike's front wheel and see if the steering is smooth and tight, with the wheel in the air.

regards,
Joe  

Joe,
I agree with you.
It almost sounds like one bearing is missing, and at certain angles, one pops over to the other side. That would change the geometry, fork angle, and from original post, the angle of the bike.

It's serious, and it should be repairable... mostly labor. It depends on whether the bearings are held in place in  a race, or are more free to move about.
Probable fix involves a new bearing, and someone spending some time with grinding compound to smooth out the ding.