Good video! Well done! Aren't the nut and washer valve stems better?
I think the valve stems without any rubber -- the nut and washer stems you mention -- are better, in general, than the rubber ones that Mitch replaced (which I gather are the stock ones). You don't have the issue that caused the replacement in the first place, i.e., the wearing out of the rubber (although you do have to make sure that the nut is snug, which you or the shop can check on, each tire change).
But more specifically, if you ever decide that you want to add external TPMS sensors to your scoot, it is
essential that they are all metal. Eight years ago I wrote an article on external TPMS sensors for webBikeWorld, and researched the issue thoroughly back then.
ALL of the vendors of those sensors -- Doran, Garmin, and some other big players -- specifically mentioned this, and the company I was concentrating on, Doran, even supplied all-metal stems -- both right angle and straight -- with their sensors, just to be sure that you got the message.
(I believe Doran no longer makes these for bikes, and I stopped recommending that company a year or two after I wrote that, but that's another issue. I added FOBO sensors to my now-sold Exec, and added one brand new FOBO sensor to my new BMW C 400 GT scooter, even though I had to buy a pair of them from FOBO. BMW has a stupid system for placement of the valve stems, which precludes adding a sensor to the front wheel: it would hit a brake caliper, sort of similar to the problem Mitch discussed at the end of his video, with the rear tire.)
If you just want to add an all-metal right-angle-ish stem for convenience, I think you will find this thread to be worthwhile reading, in terms of background and what stems to buy:
Sorry, at 75 I'm too brain dead to read the 444 plus member responses for stems and trailering. Two years and 1000 miles ago I bought my 08 executive. The original owner tied it down on my uhaul trailer rental and I made it home 80 miles without any problems. I had new tires installed at a...
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