There is nothing like a flat tyre to spoil a ride or even a race when confronted with race
time restraints. With most of the mountain bike community taking advantage of the benefits of tubeless tyres, a must is to use a good quality sealant. Once upon a time, there was only one major player in the tyre sealant market, but recently a new product emerged that I thought I would try, the Orange Endurance Tubeless Sealant.
I have been using Orange Seal for about six months now. It has taken me a while to review this sealant as I was waiting for leaks, deflating tyres or even dried up sealant. Well, after six months I have only had one flat (touching wood madly). This was at one of the major races where I staked the tyre to the size of approximately 2mm plus diameter. Initially, it wasn’t sealing and as I was stressing I decided to take the wheel off, ready to install a tube. As I was doing this, I had a little luck and the leak sealed up, even if it was a little slow at first. I was on my way again, but after 10 minutes of working the tyre really hard, I thought it seemed to be leaking, so I put some more air in and finally it sealed completely. The thing I needed to understand about this hole is that it was quite a large hole, going by the stream of sealant that had been coming out initially. I am still using that same tyre as a tubeless setup and cannot find the repair.

My first use of Orange Seal was that it appeared a lot thinner in consistency, and when setting up the tyre upon its first mounting, it sealed very quickly. This could depend on the tyre manufacturer, as some fit on the rim tighter than others, but I believe it was the sealant.
Orange Seal has two types, Regular Sealant and Endurance Sealant, which come in a variety of sizes, from 118ml to 473ml.
I can only vouch for the Endurance Sealant, but I have read where the Regular Sealant performs sealing holes of 6mm, although the consistency is a lot thicker. I can vouch for Orange Seal’s Endurance Sealant as a solid performer in terms of installation use and its effectiveness at sealing punctures. It has proven to last and still be of a usable consistency as opposed to drying up after six months. I am not too sure how its use will be with larger holes, but in comparison to the previous sealant I have used, there appears to be little difference.
By Mark Brockwell - Masters MTB Rider, Pushys Sponsored Athlete