When I recently bought my new MTB: CUBE ACID 29" 2017, the shop put sealant liquid in the inner tubes. So far so good, great, no punctures, no loss of air, really happy. My questions: How often (or mileage) do I have to add liquid? Do I have to replace the inner tube? Any other recommendations about that? Thank you all!

  • 1
    Do you mean the sealant went into an inner tube, or do you mean it's tubeless with sealant?
    – brendan
    Commented Apr 2, 2017 at 16:59
  • It is clear: the fluid is into the inner tube, which means I am not running tubeless.
    – Alex Par
    Commented Apr 3, 2017 at 8:16
  • 1
    Honestly, if you have properly inflated tubes, sealant is superfluous, and I'd just omit it next time. For things like goatheads or whatever, I'd go with a thorn resistant tube instead.
    – Batman
    Commented Apr 3, 2017 at 12:36
  • If you use a tyre with reliable puncture protection, like Schwalbe Marathon or Road Plus, I'd argue that it doesn't make any difference how much sealant you keep in the inner tube: spikes will not get to it, unless you work in a steel nail warehouse and use your bike to ride around it. Commented Apr 4, 2017 at 17:26

1 Answer 1


It depends. If you have regular tube tires and the sealant was something like Slime, then in theory you don't have to put more in unless you have a flat. In reality, Slime thickens over time. You can't really add more, so you might expect to change tubes every couple years. Riding your bike regularly will help prevent the Slime from coagulating in one spot and causing an unbalanced tire.

If you have tubeless mtb tires, and used something like Stan's then you should reseal every 2-6 months according to the manufacturer, more often if you have punctures or loss of air.

In either case, you want to keep the total volume of sealant the same over time. Which means you do not want to add more unless some has leaked out or you're able to remove it through other means (this is easy with tubeless tires; it's near impossible with tubes).

  • So, in order to not overfill the inner tube (I have no tubeless), I assume I should wait untill the 1st flat tyre and then add a little more. In that case is there any drawback,,except the risk of the 1st flat tyre? By the way, having the fluid in the tyres is there any precaution I should take or make some kind of manipulation or maintanance in order to keep the fluid and tyre in good condition?
    – Alex Par
    Commented Apr 3, 2017 at 6:44
  • 1
    Adding to the "it depends" line of thinking: It also depends on the climate you live in. In more arid areas, stick to the 2 month side of the 2-6 recommendation. Commented Apr 4, 2017 at 14:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.