Tyre pressure sensor leaking after tyre change

I've just had new tyres fitted front and rear on my 2015 GS, and now there is a slow leak around the front valve. The leak must have been quite fast when I left the tyre fitters, because after a few miles I knew the tyre was going soft so went back to the fitters. They tightened the hex nut around the valve stem, but said it might require BMW's RDC repair kit to fix. They reckoned it was due to the stem being disturbed when they changed the tyre, plus some corrosion around the valve stem. BMW's RDC kit is £25 for a hexnut, Schrader valve and a rubber seal!! I had a similar problem last time I had the tyres changed (same company).

So, my questions are:

1. Am I just unlucky or are the tyre fitters hamfisted muppets who have damaged the valve?
2. Have other people had similar problems when tyres have been changed?
3. Is there an alternative to the BMW RDC kit (preferably one that doesn't involve taking the tyre off the wheel)?

Thanks, TC

Pain in the Arse, you can buy a seal kit from BMW...Mine went in the Bin

Your not unlucky. They are hamfisted. I’ve changed a few tyers with that system with no problems. JJH

GS, so I assume alloy wheels? If something is leaking, it's not the RDC sensor, but the valve located at the side of a spoke, partnr. 36317693061 (which already includes the rubber seal ring and interior part of the valve). Got two for my alloy wheels after powdercoating and did pay something like € 7 or 8 per piece.

The sensor itself is held onto the inside of the rim with a hollow bolt which screws into the bottom inside end of the wheel spoke the valve sits on. The interior part of the valve is a standard Schraeder valve core. Are you sure that's not loose? I can't understand why they would touch the value assembly.

I have experienced the same issue last year on front wheel of my 2015 GSA. Fortunately I’ve just tightened the valve with spanner a little and leak stopped.
I am sure tyre fitter disturbed the valve at the tyre change.

It’s not a good design. Just check that when the tyre was changed the guy didn’t try to break the bead by the TPS. I have seen the hole ‘ovalled’ by a ham-fisted tyre changer. Why do people need to touch it? Don’t you just remove and change the valve? Why loosen that nut at all?