Sludge Pro Series sealant is designed for presta valves, and getting the Sludge into the tube couldn’t be simpler as it is thin enough to flow through a presta valve.
We would advise following the instructions and using petroleum jelly on the valve, as this helps to keep the valve clear. Each bottle contains 100ml, enough for two tyres.
The sealant has saved me many times from frozen fingers on the roadside; and although stones have penetrated leading to a slight loss of pressure, I’ve never had a completely deflated tube.
It has also allowed for a mid-weight tyre to be used in preference to a heavy winter version.
The downside is that a 50g weight penalty is added per tyre, and if you do need to let the tubes down you’ll need to leave the valve core at the highest point for a few minutes or expect to see Sludge everywhere.
Sludge Pro Series sealant does what it sets out to do – helps to prevent punctures. It's easy to get into the tube, although there's a slight weight penalty.