I have just bought an Alfine 11 (and a front wheel) with DT Swiss rims. As the rims were lined with gorilla tape, I thought I’d have a go at setting them up tubeless with a couple of old Racing Ralphs I had in the tyre pile.

The tyre beads were brushed with a strong soapy mixture, 60ml of Stan’s inserted in each and then inflated with a compressor. After some leakage (old cuts etc) they seemed to have sealed ok. However, they are now both deflating slowly overnight and leaving a sort of brown oily residue on the conservatory floor.

Any idea on what’s going on here – some sort of reaction between the soap/Stans/gorilla tape/older rubber perhaps?