In terms of what is available to put on your bike for tubeless tires for 29″er bikes, the choices are getting better, but it isn’t any secret that most 29″er riders that run tubeless tires are still “converting”. Taking products not designed for use in a tubeless context and “making do” with them. Even this humble writer can claim this “transgression”.

It is interesting to note that a whole category of products is available for you to pursue your “habit” too. Whole companies are based upon this “conversion” of non-tubeless product to tubeless uses. This isn’t anything new. It goes way back into the mid-nineties as far as the roots of the techniques we use today are concerned. What is new is how this technology and 29″er tires and rims have changed the game for not only users of this “dark art”, but for the tire and rim manufacturers as well.

First off, it needs to be explained why one would do such a conversion in the first place. The desire for tubeless tires can be traced to racing. Racers were looking to rid themselves of more rotational mass and in the process of converting the standard folding bead tires of the day, they also discovered an advantage in traction and lower rolling resistance. Sealants were developed from latex that allowed the porous sidewalls to stop leaking air and also helped with punctures. It wasn’t long before other riders were adapting this technique for their own trail bikes. Things were progressing at such a rate that Mavic and several tire manufacturers stepped up and developed the first commercially available tubeless rim/tire systems dubbed “UST” leading at least one popular magazine of the day to write that “tubes were dead”.

Well, tubes are still in wide use to this day, but tubeless advantages were well known and tubeless systems were readily available for 26″ers at the advent of the modern 29″er in 1999. Early adopters wanted tubeless tires on their big wheels too, but of course, there were no UST systems available, and no tubeless conversions yet for 29 inch tires. That didn’t stop riders from trying though, of course. What resulted was a string of failures mostly due to the different physics at work with 29 inch wheels. Tires were made with segmented beads, or beads that were up to 26″er strength standards, but used tubeless in a 29″er size, were too weak. These tires were failing left and right. Even using some early 29″er tires and rims with tubes was causing intermittent failures. Riders blamed loose fitting tires, or undersized rims, but it is also worth pointing out that this was all new territory for manufacturers and new methods for making 29 inch product was obviously necessary.

Several things have happened since those earlier times. There are dedicated tire/rim systems for tubeless out now in 29″er sizes with a decent amount of selections that satisfy most riders. However; there still are several tire and rim manufacturers that have not publicly stated they are selling products that are tubeless compatible, or are saying so in a very subtle way. This leaves riders with a situation that is ambiguous and the lack of manufacturers leadership in terms of what does and doesn’t work is troubling to many riders.

The result is that today a rider opting for a tubeless system may go with a complete system, or in many cases, a choice between competing systems components mixed together, and finally may end up with doing their own conversions on components not specifically designed or approved for tubeless uses. How does one know what works and what doesn’t? That is a good question that raises debates on forums, trail heads, and in bicycle shops all across the world. Trial and error still reigns supreme in the area of finding out what will be reliable as a tubeless tire set up for 29″ers.

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This writer has experienced several intermittent sidewall failures in converted tubeless tires.

While this is not an ideal situation for 29″er trail riders, it is interesting to note that the rate of failures has decreased from the earlier days. I recall one tire manufacturer’s employee telling me that they were taking their entire line of 29″er tires, converting them to tubeless, (using a “ghetto system” popular then), and hearing several explosions from the room where the work was being done. The results were one extremely latex soaked employee and a total redesign of the tire line up for 29″er sizes. Interestingly, this company still does not offer tubeless ready 29″er tires. That said, we also do not hear about failures running these particular tires anymore either.

So, the question is are tires and rims being designed with possible tubeless conversion “abuse” in mind? Maybe. It is obvious that manufacturers that do not produce tubeless ready products are making modifications to older models or designing new product that, if not done with tubeless conversions in mind, are certainly making it easier for riders to convert these products. That said, failures still occur. Sidewalls in tires meant for tubes have extra stress placed on them when run tubeless and may fail. Rims not designed for tubeless conversions may still allow tires to pop off the bead seat. Combinations of tires and rims designed for tubeless use may not be compatible with each other, causing more troubles.

2010 is bringing more tubeless compatible rims and tires to riders. Hopefully a “standard” will be reached at some point which will allow riders the peace of mind that the tire and rim they have chosen is a compatible pairing. Perhaps a time will come when all 29″er tires are tubeless ready out of the box. Maybe all rims will come with sealed inner rim walls or recommended rim strips to make tubeless set ups less experimental. Until that time, converting to tubeless tires on a 29″er can still be fraught with peril.