Mavic Cosmic Elite


So the wheels came after about a 2 weeks stint of them, no being in stock on first view lovely build quality. Wheels were 100% true radial and lateral which I have never had before straight out the box. the UST tyes calm mounted already to the tyres which were nice but you will see later on in the installation why this didn’t really help. In the box calm a little booklet given you the main details of the wheel and an extra year guarantee taking it to 3 years instead of 2 if they were registered. The Yksion tyres 700 x 25c which use the Hutchinson storm 11 compound which is supposed to be grippier, more durable and lighter. Nice set of screwers and Mavic Tubeless tyre sealant I did by slime sealant just as reviews said it was a little bit better and for the normal slime that goes into innertubes has done me wonders so I stuck with the brand.

The tubless perks are supposed to be that they can run a higher pressure so we are looking at instead of 100 -120 psi we are looking at 100 – 200 psi depending on tyre build and brand. Higher TPI casing the higher the thread counts the smooth the tyre is supposed to be resulting in a low rolling resistance and the fact your running no tubes and doesn’t get any friction between the tyre and tube resulting in lower rolling resistance. ( the low rolling resistance the better ). The UST system that Mavic pioneered on the mountain bikes has been moved over to the road bikes and has some slight limitations the Tyres themselves have a limit of 110 psi and 127 TPI which are both the same as its non UST tyres ( the Yksion that I am running already ) the only difference is the compound used. Which when in hand is very clear the UST Yksion are a lot thicker this is needed as its the only thing combined with the sealant to stop punctures. which I was a bit sceptical about but after watching the video of 3 20mm carpenter nails being pulled out the tyre and all sealing.



The first step is you need to measure out 30ml of sealant for each tyre, Shake the sealant well no matter if you using Mavic own brand or slime. Shake well to break the bits up otherwise it will just clog you syringe if you are used it or the value depending what way you are getting the sealant into the tyre. One thing Mavic could improve is having a window on the side of the syringe so you know how much is in the tube instead of guessing. One thing I did notice the Tubless slime is a lot thicker than normal slime. I also believed its based off of a latex instead of the fibre base. The big difference I found between the Mavic and the slime sealants the Mavic is a smooth liquid while the Slime has lumps of fibres but not as much as the normal slime. The Mavic sealant also has to be replaced every six months and you cannot use co2 inflators as it freezes the liquid. the Slime last between 8 months and a year and can be used with the C02 sealant.


Once the solution is measured out you just attached the syringe/bottle onto the tyres value that you have decored. Mavic came with a nice but simple tool to do this very quickly. Once the solution is in you need to spin the wheels for 30 seconds which spreads the sealant around the tyres evenly. I did this for a minute just to make sure it’s fully spread throughout the tyres.


Once that is done I pumped up the tyres to 50 psi and tested for air loss, Which I did have. I could see the sealant slightly bubbling by the bead. This is because the tyres themselves weren’t seated probably this is my fault for not checking. To fix this without having to remove the now already preslimed tyres I removed the air added sealant onto the side walls reseated the tyres pumping them up in 10psi interval spinning between increases to 50 psi.




Once the tyres had stopped leaking air I cleaned off the sealant of the sidewall pumped up to a maximum of 110psi and installed them onto the bike. Due to me just being sceptical I adjusted the brakes and checked the bikes pressure every 30 minutes and no drop in pressure. The wheels are all ready to ride so what I will do is give you a review on the 1st day riding then maybe a review in a week, month then 6 months to see if anything changes or if any problems occur. The wheels themselves especially the bearings feel amazing and seem to spin forever people is just a small video of the wheels in motion.