Slime and non removable presta valves

steve_sordy

Wedding Crasher
Nov 5, 2018
8,451
8,694
Lincolnshire, UK
Into inner tubes?
Yes, cut a small slit into the inner tube, on the side facing the rim. Insert the Slime, preferably without getting any Slime on the outer part of the tube. If you do get any Slime on there wipe it off and then clean up with some iso-propyl alcohol. Then apply a tube patch.

I would consider relegating that tube to a spare to carry in your backpack and instead fit a tube that has a removable valve core. Or buy a ready filled Slime tube.

Maybe I have used the wrong sealants, but I have never had much luck adding sealant through Presta valves (core removed). OK the tyres are tubeless, but the valve is common. When you think about it, if the sealant is supposed to be so good at stopping up holes in tyres/tubes why is it expected to pass so easily through the narrow Presta valve?
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
13,815
20,507
Brittany, France
Make a hole in the tube large enough to get the slime in ..... but small enough for the slime to seal it :)

Normally easiest to just buy some with it in already.
 

Andy.M

Member
Nov 25, 2020
151
90
Rochester UK
When I ran tubes with slime I used to buy Continental tubes that have removable cores and used the one I took out as a spare for emergencies on the trail.
 

Monkey Dog

Active member
Jun 4, 2020
250
166
Derbyshire
Into inner tubes?
Maybe I have used the wrong sealants, but I have never had much luck adding sealant through Presta valves (core removed). OK the tyres are tubeless, but the valve is common. When you think about it, if the sealant is supposed to be so good at stopping up holes in tyres/tubes why is it expected to pass so easily through the narrow Presta valve?

Just today, I've put Muc Off tube sealant into my tubes by removing the Presta valve core. It was a doddle.
 

KennyB

E*POWAH Master
Aug 25, 2019
824
563
Taunton
Once tried putting Stan's sealant into a tube. Didn't work, when the tube punctured I just got a load of liquid sealant in between the tube and the tyre. Apparently it is the spray of sealant from the tyre reacting with air that does the sealing.
 

steve_sordy

Wedding Crasher
Nov 5, 2018
8,451
8,694
Lincolnshire, UK
I use Continental Revo sealant. It is a milky white latex type, originally formulated for Continental tyres (so say Conti). If I don't shake the bottle, the sealant goes straight in through the valve. Then one day I noticed sludge at the bottom of the bottle and realised that the sealant had particles in it. Therefore for almost two years I had been leaving them in the bottle!! Once I started giving the bottle a vigorous shake, the sealant would not go through the valve.

This may explain why I used to see sealant leaking out from time to time (spurting one time). I'm assuming from the various posts above that Stan's sealant doesn't have particles in it? Further that it relies only on the sealant reacting with the air to form a seal. It obviously works, or it would not be so popular, it just doesn't sound as good.
 

jimbob

Active member
Aug 3, 2020
518
429
East UK
I've been using Halfords own brand (bike hut?) sealant filled tubes. Think they're £6 each so nice and cheap.

They seem to have a latex sealant in them, and, touch wood, haven't had a puncture since fitting them. Saves the effort of filling them yourself!
 

Russell

Well-known member
Dec 16, 2018
211
149
Iow
I tried the pre slimed tubes but I still got punchers. I just drill the rim out to ,I think, 8mm then fit Schrader valved tubes and stick half a big £15 bottle in each tyre.
I've not had a puncher ages now. I did have some trouble with a leaking valve due to slime when I tried to adjust tyre pressure on the trail so I would recommend not doing that.
 

Growmac

Well-known member
Subscriber
Dec 4, 2020
381
443
Wilts, UK
In 20 years I’ve never encountered a presta valve with a non-removable core. Are you sure? The stem unscrews about 2 mm below the little section that locks the valve closed. You can get specific tools, or it’s easy with a pair of pliers
 

Kingerz

Active member
Jul 11, 2021
200
172
Australia
In 20 years I’ve never encountered a presta valve with a non-removable core. Are you sure? The stem unscrews about 2 mm below the little section that locks the valve closed. You can get specific tools, or it’s easy with a pair of pliers
Yeah they are usually a solid unit and non-removable. I have to order ones with removeable cores. Just Google if you've somehow never seen one such as presta valve non removable core - Google Search[/QUOTE]
 

Konanige

Active member
Feb 29, 2020
422
336
Mendips
Non removable is usually the cheapest crap you can get, more likely to puncture too. I really don't understand why anyone uses tubes these days, there's absolutely no advantage. If you had a slime tube in your tyre that didn't seal when it punctured, then it was probably a pinch flat, which wouldn't have happened if you were tubeless.
 

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