Val e stems

[Gene]

 I have factory mag wheels on my 85 650sc Nighthawk. I'd like to replace the rubber valve stems with metal ones, but I'm not sure that can be done, perhaps the brake disc's would interfere with the inflation chuck. I looked metal valve stems up on Amazon, I didn't see height specs. If it is possible, I know the whole assembly will need to be re-balancèd.

[Larry Fine]

You can get angled stems. I put tee stems on for a TPMS.

[mollusc]

I mount my own tyres.  I meant to put angled stems on the last time I did them but ran out of time.  Provided that you have enough room to get to the valve, there's no reason why you wouldn't be able to do what you're planning.

[Bob H]

I put tee stems on for a TPMS.

I did the same and love them. Pricey (from FOBO for my TPMS)
Aside from the TPMS, those have longer thread region than the common "bikemaster" ones that everyone else sells.
I was really, really reluctant to even ride with the bikemaster ones. Maybe they would be OK for a very thin rim, but for my vintage bike I was shocked at only getting about 2 turns on the nut before it snugged up. No I didn't double up the gasket thing.

There are some other ones that have a 45 degree angle (not 90) with appropriate thread length that also work great but I don't have the link right now. If you search with thread length in mind, you will find something that works. The diameter isn't the problem, I think everything but Ducati and other odd brands use the same diameter as Honda.
https://my-fobo.com/accessories

The TPMS makes it mandatory to have metal stem. There are reports of the rubber ones breaking with sudden loss of air due to weight of the little TPMS thing at the end of the stem.
You can buy a dozen of the rubber stems really cheap, and I used to just replace them every time I changed my tires. Nothing wrong with them unless you have access challenge and need an angle. Don't forget to snug up the little core inside, regardless of what valve stems you choose whenever they are replaced. I have had a couple with slow leaks that turned out to be the core slightly loose when I spayed soapy water everywhere else and couldn't find a leak.

[Bob H]

For a non-T stem these are great. The threaded area is long enough to work on the older rims like mine.
https://www.amazon.com/gp/product/B09FP6Q8WJ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have one of those on my front wheel, ready to change out with T-stem when I replace my front tire soon.

[Bob H]

I have factory mag wheels on my 85 650sc Nighthawk. I'd like to replace the rubber valve stems with metal ones

I found photos from one of my earlier tire changes. The common "Bikemaster" 90 degree stem at far right doesn't have long enough thread area for older rims.


The T-stems that Fobo sells work great on my rims, they have adequate thread length.

If you are not using TPMS and have no need for a T-stem, the 45 degree ones Amazon sells worked great for me.
Next photo shows installed