Thursday, November 16, 2017

Thoughts On Tubulars For Gravel Road Riding

A 40mm tubular from FMB proposed for gravel racing. Image pinched from BikeRumor.com
The tubular tire has a long history in cycling going back to the 19th Century. Basically, a round "tube" makes up the tire cross section. The tube is then made circular and tread is attached to the outside circumference of the tube. That then is glued to a rim which is specifically designed for this type of tire. This process of gluing can take quite a bit of preparation and time.

Flat tires can be ridden on, (until the tire carcass shreds or comes unglued), but repairs to tubulars are not often done and then only by skilled craftsmen and not immediately in the field. Typically one either carries another tubular tire pre-glued for replacement or one has to change out wheels from a "pit" on course or from a support vehicle, as you see often in Pro road racing.

So......why would one want a tubular for gravel road riding or racing? Well, for one thing, pinch flats would be non-existent theoretically speaking, as there is no traditional tube which would be separate from the tire to pinch. However, a cut tire is much more likely, if pressures are run low. Secondly, tubular tires have famously low rolling resistance and corner very well. Finally, there is a certain faction of cyclists that would find running tubulars something that would tickle their romanticized notions of cycling. So, for them, it would be justified.

I've written about the possibility of tubular tires for gravel road riding before here. In fact, I was so curious that I had Velocity build me a set of tubular wheels to try it out on based upon a tip from the folks at Challenge Tires years ago that they, (or someone) was going to make a big, wide tubular. That didn't happen so I actually laced the hubs over to some clincher rims this past Summer and hung the rims from the rafters.

With the typical gravel here in Iowa being chunky, loose, and deep, would tubulars survive the punishment?
I think certain places would do well with tubular tires. I think about Southeastern Minnesota, as an example, or anywhere the gravel is smaller in size, not very deep, hard packed, or really mostly dirt. However; that isn't what you will find everywhere, or in most areas that have unpaved roads. So, to my mind, this idea doesn't have enough merit to convince me that it is a solution that is better than a tubeless tire. While tubulars can be fantastically light, that probably isn't a good idea for a tire that will be getting constant roughing up by loose gravel. Not to mention riding anywhere there are puncture makers like goat heads and other thorny, pointy nasties on roads.

Tubeless tires typically are pretty bombproof out on gravel these days. It isn't impossible to have a flat, cut a tubeless tire, or to have some other issue, but those instances where tubeless gravel tires fail is rare and getting ever rarer. Even tubed tire use is easier on the maintenance side, and repairs are a snap in the field. Tubulars? Not so much.

This all has become relevant again because of a company famous for making tubulars, FMB, which has come out with an idea for a tubular gravel tire. (See the BikeRumor.com article here) In my opinion, this FMB tire is a stab at seeing what the reaction to a tubular for gravel racing might be. There is really no sense in the tire shown otherwise since the casing is huge, exposed badly on the sidewalls, and the tread is simply a CX tread glued on to this bigger casing. It isn't a practical design.

If this gains favor amongst racers, and FMB actually does a design worthy of use, which this design exercise clearly is not, then what? Well, it will be one more reason for the riders who are using these to call for support vehicles. I mean, you aren't really going to expect anyone in their right mind to carry a spare tubular and rip off the damaged tire, replace it with a pre-glued spare in the field, and carry onward, are you? Of course not! This isn't going anywhere unless gravel racing becomes just like Pro road races. So, unless the UCI gets behind this, or unless gravel races open up to going in the direction of Pro road races, this idea has zero merit. Because tubeless tires are already a far better idea than this is.

6 comments:

Doug Mayer said...

Tubeless, all the way. Never looking back.

Kevin Collings said...

I'm going to hate it when it finally happens, but I hear more noise about full support (to the point of having support vehicles) every year. This coming year in particular there are some newer "national" type races that were catching flak for not running full hand-holding to attract "pro" level talent. So if promoters wind up listening to this loud (but hopefully small) subset, the support that would be needed for tubulars to be a thing in gravel races might be coming to at least some races.

Those will definitely be races off my calendar though, support crews following riders around would be horrible.

Robert Ellis said...

I glue on sew-ups for Cx racing and it is a 2 or 3 day process (at least the way I do it). The advantage is one can run lower pressure and corner more quickly. They are noticeably smoother than tubed or tubeless set-ups. The lower pressure makes them feel kind of squirmy almost like you are going flat, or like they are going to roll off. That takes some getting used too. I usually run some sealant in them as well. It is a MAJOR pain to tear them off when you need to replace the tire and it takes some maximal elbow grease! Their role in distance gravel riding? I think almost none. If you have a problem out on the road its not like you could put another tire and tube on those tubular rims. You would have to have someone following you in a vehicle with a bunch of spare wheels, and that's not going to happen nor do I want it too. So my opinion is there is no role for tubular set-ups in distance gravel riding what so ever.

Galen Murray said...

I used tubular tape in the setup I did this fall. I haven't ridden them much, but the setup was easy. What are the disadvantages of using tape versus glue? I've ridden my tubies on gravel stone, they are light and roll nice. I do have a tubeless setup though for longer rides.

Robert Ellis said...

I use glue, then Cx tape, then a couple more layers of glue on the tape, then glue on the undersurface of the tire and then I wrestle it on, usually making a big mess in the process. I've been chastised and pretty much banished to the garage or porch for this activity. The shop guys have been cool and let me hang out in back and do some of the work there. I've heard of using tape only for road tubulars, but those are really high pressure set ups and all that pressure helps keep those tires on. I would be real leery of tape only for cx or gravel, and for that matter, road as well. I've never really tried them on the road because I felt that rolling one of them would be a total disaster. However, I know some folks who have used them, tape only, on the road and really liked them and had no problems.

Richard Stewart said...

I wouldn't say there's no place for them. It's justified at the UCI level because of the increased performance they provide. The few off-road and gravel competitors I know who use tubulars like Dugast, Challenge and others do so with sealant in them to mitigate punctures from goatheads and the like. It's very doable to carry two spare tubulars lashed to your bike, but I wouldn't recommend trying to corner like you're on rails. Lennard Zinn does it - the guy who has written virtual bibles on bicycle repair - and he's never had a DNF using tubulars off-road. I think it's about the return on your investment: Do whatever you believe will get you to the finish line the fastest with the least amount of frustration and consternation. I train on clinchers and race on tubulars, but I didn't even start doing that until I rode with the Germans back in 1987 while living and working over there. I think it says a lot that tubulars are still the go-to for most of the pros and non-mortals. I'm gonna try both over the course of this season over some gravel courses so I can gather my own (very possibly trying, as well) empirical data.