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Overview

How Does Muc-Off MTB Tubeless Sealant Seal Punctures?

Muc-Off MTB Tubeless Tire Sealant pairs an advanced latex that forms a strong seal fast with sealing particles that fill bigger holes and tears. It seals tears and holes up to 7mm, and it also seals porous tires and bead and rim gaps.

The 140ml pouch is designed to fit right over a Presta valve, and fill lines on the pack show how much to add for your tire size. Muc-Off made the pouch to add to your toolkit or ride pack for emergency top-ups on the go. Muc-Off's fill chart covers 26 and 27.5 inch MTB, 700c cross, 29 inch MTB and downhill tires.

All the specs

MPN 821

Volume
140ml
Format
Pouch with fill lines, fits Presta valve
Seals punctures
Up to 7mm
Fill chart sizes
26/27.5 MTB, 700c cross, 29 MTB, downhill
Formula
Advanced latex with sealing particles, ammonia free

FAQ

Good questions

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How do I inject the sealant from the pouch?

Remove the valve core and shake the pouch well. With the valve at 12 o'clock, push the pouch over the valve, then rotate the wheel until the valve is at 6 o'clock and squeeze sealant in, folding the pouch to the fill line for your tire. Reinsert the core, inflate, then spin the wheel and rock it side to side to spread the sealant.

How often should I top up tubeless sealant?

Muc-Off rates it to last up to 6 months or more in temperate climates. Check the amount in each tire regularly and top up as needed, especially in hot, dry riding above 35°C or every 750 miles.

Is 140ml enough for a full MTB tire conversion?

It depends on your tire size. Muc-Off's minimum per tire is 60 to 75ml for 26 and 27.5 inch MTB tires, 105 to 140ml (or the whole pouch) for 29 inch MTB tires, and 120 to 140ml (or the whole pouch) for downhill tires. You can add up to 30ml extra for more protection.

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