Back in the day, I knew “someone” whose steering was soooo notchy, it affected the handling of his bike greatly. We quickly put the bike on a stand, pulled back the lower bearing seal enough to get a spray tube in and proceeded to spray WD-40 in every place we could around the seal. After holding the seal lip open to let the WD-40 drain, I sprayed some lithium grease in it and turned the handlebars back and forth until the solvents evaporated (these solvents probably redistributed the old grease, too). It worked perfectly and BTW, this whole operation probably took less than 5mins. Then this "someone" grew up to be an aerospace and software engineer, got a couple of divorces, dropped out of high tech and went to low tech, and I still don't lube my, er, I mean "his" front end the recommended way (sheesh). Will I never learn?
(segue) Here's a quick cheat: every year or three (or if your steering is "notchy" and you dread dealing with the bottom steering stem bearing) rinse your stem bearings out and re-grease. It's pretty easy: set your bike on a stand with the front wheel just off the ground. Remove the handlebars (and put'em in the reinstalled upside-down clamps so you don't hafta disconnect any brake lines or cables) and remove the upper triple clamp. Let the front end gently drop 2-3” down to the ground. The top bearing can be easily removed and cleaned. The bottom bearing is now exposed: take a can of WD-40 with a spout and spray/flush the old grease out. If you wanna eye-opener, catch the residue in a container and look at all the junk in there. Lather, Rinse, Repeat. Use most of the can, you're gonna get a lot of crap out. Now re-grease with your favorite grease. Use lots- even though this bearing doesn't turn much, the grease is acting as a barrier to contaminants. Don't forget the races, too. I'd guess 60% of the trouble/crap will be in the lower bearing- these bearings are exposed and not sealed very well. Put the upper bearing in, pull the front end up- use your foot under the wheel to hold while put the triple clamp on. Button everything up (well okay, that's a broad brush but I can't detail every step). Now pressure wash the neck area with 2000psi 180° water/soap mix- don't forget the electrical connections, too. ok, ok JAFJ- I can't help but to rant once every so often. No wonder I never post.
BTW- grease. You are not supposed to mix grease with different bases (Li vs soap/Na) but in this low rotational application- eh, who cares?. Or follow the next hint and use a high temp automotive grease that's "waterproof" (a-hem... IOW, just about any auto grease). Also, I'm not sure how much heat the oil cooler and frame reservoir add (some, I'm sure. But enough to worry about?) I'm gonna try candle wax someday or unsalted creamy peanut butter just to see. Okay, maybe not... ...but I don't think the type of grease in this application is a big issue.