Been on hols for a week and come back to find the back wheel on the SO's gravel bike flat.
Pumping it back up, air and sealant is escaping through the actual metal of the rim surface (not spoke holes or valve)
Now obviously the rim tape has let go at some point to get air/sealant into the rim cavity in the first place, but its a bit worrying that the sealant appears to be corrosive enough to eat it's way out in multiple places. Is that actually a thing??? It seems to be mostly places where the ano has been scratched by rock strikes.
The rims are WTB KOM i23s. I recall I did have a pig of a job getting the tape to seal initially (built in winter and I couldn't get the Tesa tape to stretch/stick properly in the cold), so that's when the sealant got in, but I did wash it out when I retaped and they're only 18 months old...
Thoughts? I do have a vid or 2 on my phone, but no way to sensibly upload them.
but its a bit worrying that the sealant appears to be corrosive enough to eat it’s way out in multiple places. Is that actually a thing???
No.
Are they old rims? How bad are these rock marks?.
Either the tape isn't sticking well enough (try using a hairdryer to warm the tape and rim) and the air is escaping through the spoke holes or less commonly, something has punctured right through the tyre, rim and tape - I saw this with a nail and a brand new wheel and it wasn't until I removed the tape found the hole in the rim.
Wheels are 18 months old. After the initial botched tape job was redone, they've been fine. I last topped up the sealant in mid June before she did the C2C. They were holding air fine last Saturday when the bike was last used, but over the course of the week of just hanging there in the cellar, something has given way.
The rock marks - minor scratches - the kind of thing that would vanish with application of a black sharpy. It's on a gravel bike ridden by a moderately nervous lady in the Peak - not fast, but makes up for it by never, ever stopping and does a lot of miles that way.
are they pinned rims ? Maybe those can leak a bit