As long as it's stable. I use a piece of wood under the frame crossbar (by the oil filter) that is just a little longer then when the forks are fully extended to lift my front wheel off the ground. (See pic) If you have slider you can put jackstands under them, I do this when I am doing a lot of work on the bike/ front tire-wheel removal/ winter storage/ etc..
Ideally you do not want any cables or wiring to encumber/ imped the motion while it while testing how it "falls" to one side or the other. The cables nor wires should not cause much binding normally anyways and you can get a pretty good idea if you have an issue with your bearings. It can make getting the tension a little tougher though.