OKO Magic Milk versus Stan's NO-TUBES

Op 02 juli 2014


OKO Magic Milk

1. Introduction.

OKO Magic Milk is a step forward for latex-based free-flowing liquid tyre sealants. It can be used with 'tubeless ready' or full UST tubeless tyres (for maximum puncture proofing on UST we recommend Puncture Free Bike or
OKO X-Treme). It is super-light, with a dose of 30-60ml per tyre in most sports to mountain bikes, depending on size.

• NEW product for tubeless-ready conversions

• The "Lo-Fat" tyre sealant
• Also ideal for tubular sports tyres
• Lightest real-world product in the market
• Seals holes up to 3 mm (or more)
• Finds the little crevices between bead and rim
• Synthetic latex formula is wheel & tyre friendly
• Lasts longer than other latex milk products
• Suitable for all bike types

A 250 ml bottle deals with two regular mountain bikes, or four racing bikes: for 26" MTB tyres it is just 60 ml per tyre.
Simple Schrader fitting, using the valve core remover and filling tube supplied in every bottle cap: or, use an OKO Tyre Sealant Injector (especially when using removable-core Presta valves) for easy, accurate measuring.

2. Benefits

• Latex-based for sealing wheel / tyre bead imperfections
• In practice, the lightest sealant you can use
• Longer effective life than competitors - usually 9-12 months before you need to top up
• Advanced synthetic latex formula - will not rot tyres or damage wheels
• Contains corrosion inhibitors
• Washes off with water
• Non Hazardous

3. Characteristics

Non Corrosive: Non Flammable: Non Hazardous (not excluded from air shipments unlike some ammonia-containing products). It washes out of the tyre if required.
NO ADVERSE AFFECT UPON TYRES OR RIMS (contains anti-corrosion agents). WORKS WITH TUBELESS READY and FULL UST TUBELESS WHEELS/TYRES, with Schräder or removable-type Presta valves. (if you have non-removable Presta valve cores, pour the Magic Milk into tyre well then mount tyre onto rim).
For 'tubeless ready' tyres on standard rims, always use a rubber rim strip plus OKO Magic Milk. Shake the tyre/wheel combination vigorously from side to side at each point to force the sealant into the little gaps between bead and rim, and into the tiny holes in the porous tubeless ready tyre sidewalls. Also spin the tyre on the wheel for a prolonged period. Follow tyre and wheel manufacturer instructions.
(For tyres with inner tubes, use OKO Puncture Free Bike or OKO X-Treme)
Colour: White. Free-flowing. Low Odour (no nasty ammonia smell).
• Road Racing 30ml
• 26" MTB & 650B 60ml
• 700C, e-bikes & Cross 50-60ml
• 29" MTB 80ml
For maximum accuracy, for easier use with removable Presta valves, and for a host of workshop uses, use the OKO Tyre Sealant Injector.

No risk and safety labels or warnings are required since this product is not classified as hazardous under current regulations. Normal safety precautions should be taken: wear gloves and protect eyes. Rinse product off any clothes that it may be spilled upon. Keep away from children. If swallowed, see a doctor.

4. Road Tyre Test Report on Magic Milk prototype, USA professional tester:

Tubeless wheels used: Shimano Ultegra 6700 Tubeless
Tires used: Hutchinson Intensive 700x25

The first step was to completely clean the wheel and tires of their existing latex based sealant (Stan's). Some scraping was required to remove the sealant from the wheels, while basic soap and water was used to remove the sealant from the tires.

Once dry, the tire was remounted. The Ultegra Tubeless wheels do come with valves that have removable valve cores, but I opted to mount the tires, remove a small section of the tire from the rim, and pour 70ml worth of "OKO MM" sealant into the tire.

Installation was easy. Once I poured the sealant into the tire, seated the tire (was able to use a standard floor pump), and worked the sealant around the wheel/tire interface I noticed that the tire sealed up quite quickly.

Currently, I have about a month of riding on the wheels with this particular sealant, and am very pleased. Not only was the installation easy, but I normally run my tires at 90-95psi, and have noticed that the tubeless tires of holding air really well.

Knowing that tires and tubes are permeable, I lose anywhere between 5-10psi over a couple of days, but that is normal to me. Some tubeless setups go from maximum psi, to half to a quarter psi over a couple of days, and that is annoying. This is not the case with OKO.

Also, running my tubeless road wheels at 90psi, and riding them quite hard around the Washington DC area, I have not noticed any "burps" from my tubeless setup.

This truly would be my 'go to' sealant.

As a side note: I have always been very reticent using any type of sealant in tubular tires (road or cross) because when the sealant dries, it normally forms a lump, which is noticeable when riding. I normally would only use sealant as a last resort in tubulars to either finish a ride, or save an expensive tubular, but definitely not as a preventative measure. I would use OKO latex as a preventative measure in tubular applications.

5. OKO in-house testing key points (target product: Stan's No Tubes)

Puncture Sealing: Magic Milk sealed up to 4mm holes, and can be relied upon for 3mm. Stan's failed on several occasions at 3mm.

Tubeless conversions: Magic Milk was more reliable, easier to fit and formed a stronger bond with the rim strip, producing less 'burping' on rough terrain than Stan's.

Longevity: Stan's dried out, forming lumps, after 3-6 months depending on temperature conditions. Magic Milk was still liquid after 6 months and went on to 9-12 months before drying, with less tendency to ball up, so that topping up was easier and did not require stripping out of the dried latex material.

Magic Milk testing carried out by worldwide OKO bike distributors in:
South Africa


Milk tests

OKO MAGIC MILK versus Other Latex Milk Sealants

Magic Milk (MM) has a little more 'body' than Stan's. Whereas Stan's is very runny like skimmed milk, MM is more like semi-skimmed milk. That may make MM take slightly longer to seal up the holes when you do a conversion: but it will last much better and will deal with 'burps' on the trail.

We have been getting excellent feedback from Distributors, purchasers and testers worldwide, and it looks like we have a real winner with MM.

We also carried out 'non-bike' tests with MM, Stan's and Vittoria's Geax Pitstop TNT, from Italy. We found that both MM and Stan's work down to -15 C without freezing, but Geax freezes below 0C; it does not have any anti-freezing capability. Also, like Stan's, Geax is natural latex and has the same horrible ammonia smell: but it is grey and it forms lumps very easily. Both Stan's and Geax run down the sides of a smooth glass milk bottle to the bottom and hardly remain on the sides at all. This is a severe test of whether they have the ability to 'cling' to the insides of the tyre wall.

Whereas MM forms a thin, even, liquid seal that remains attached to the whole of the bottle wall - this is why it is so good at filling the little porous holes on the walls of tubeless-ready tyres, and all the other gaps: and why it is a more effective sealant. See the differences in the attached picture (note the lump of frozen Geax). I recommend you do the same test and show it to people.

Consistency Skimmed milk Semi-skimmed milk
Colour White Milky-white
Base content Natural latex Synthetic latex
Smell Pungent ammonia Little or none
Effect on wheels Causes corrosion None
Effect on tyres Rots casings None
Usage period before drying 3-6 months 9-12 months
Dosage (26" MTB) 60ml 60ml
Max. claimed hole sealed 3mm* 3mm*
Safe for air shipment No Yes
Cures to seal bead/rim gaps Yes Yes
Clings to sidewalls No Yes
Bottle dosing feature None Schrader
Valve core remover Sold separately Schrader supplied
Presta/Schrader Injector Sold separately Sold separately

*Testing notes: in comparative tests, the OKO seal was stronger and more permanent than the Stan's seal.