Tubeless- more data

Turkey cross- Dura-ace wheels around 40 PSI no problems. Picked the Dura-Ace because they are lighter, roll better and there was no compelling reason on that day for really low pressure.

The following week the bike and I took a trip to Portland Oregon for “work”. I really did make it to a bunch of meetings and a conference. But I also found time to:

1. Ride the cross bike up into the Coastal Mountains outside Corvallis (very low mountains by local standards- less than 500 meters of elevation gain) on gravel roads and a bit of o so smooooooooth Oregon single track. What goes up must come down – and in this case down fast- very fast.
2. Go for a pair of rides in Forest Park in Portland. About 20K of gravel road that is closed to cars located in the trees above the city. The road was a rolling, twisty mud-pit – it was also pretty rough for gravel roads- at least by Southern Ontario standards.
3. Race in a Cross-Crusade race. Lots of climbing – and no mud on a course that was pretty bumpy.

I brought the Dura-Ace wheels – mainly because  knew that I was going to be going on some long rides- alone and in the case of the Corvallis ride - far from traffic and cell phone coverage. The thought of spending an hour wrestling the tires off the Mavics if I got a flat was not high on my list of vacation plans. I did not bring a floor pump so I filled the tires to 40 PSI when I left home, and did not touch them for the trip. Everything was flawless. I also talked to a bunch of people in Portland running all sorts of tubeless set-ups – and most were very happy.

Kelso – day 1 the mud-fest. Finally time to race the Mavics. Ran just under 35 PSI and they worked pretty well. No burping, no air-loss and better traction than I would have had with the Dura-Ace set-up.

Kelso Day 2 and Barrie- Back to the Dura-ace wheels- they are just plain faster if there is traction – and then there is the stopping – obviously an issue unique to my rig but the Dura-Ace rims are a bit wider and up front they work much better with my brakes than the Mavics. Both days trouble free.

Toronto Day 1. I pre-rode on the Dura-ace and was doing fine on the flat sections but the short climbs sucked- so I switched to the Mavic on the rear and kept the Dura-Ace up front. Ran about 30 PSI in the back maybe a tad less? Much better traction getting up the short steep stuff – and the front end was fine. Again both wheels ended up at the same PSI as they started and no problems.

Toronto Day 2-same set-up as the day before. Did not add air to the tires from the day before – hell it was hard enough to get the bike clean enough to shift properly. And again no trouble. The rear end hooked up great. On the steep climbs I was able to stand and put down full power with only occasional slippage – and I was passing people on the hills who were having all sorts of trouble. And I think the higher pressure up front created at least the sensation of more control on the way down. Was it as good as Tim Johnson’s set-up? I doubt it. But it was way better than clinchers.

So here is what I know at nearly the end of the season (say it ain’t so!!). First, the Dura-Ace set-up has been trouble free but only if I keep the PSI above 35 – and probably best above 38. So for really crap conditions you can not run the pressure you would want with the Dura-Ace – but it is better than clinchers with far less likelihood of flatting / blowing-up at similar PSI.   And speaking to others with the same wheel and tire combination you usually get the same response – it works but I don’t trust them much below 40 PSI.

The converted Mavics on the other hand seem to be fine at pressures that put the rim at risk of being dented. I can not imagine running any lower pressure than I ran this weekend. But I also know that the tires are on so tight that getting a flat would suck- so they are fine for racing but not for much else.  Based on my data gathering in Portland people who are using something other than the Hutchinson tires don’t have this issue with conversions so at some point over the winter I will mount something else on these rims and see what happens. And Stan’s has finally brought out their tubeless cross tire which looks pretty sweet – so that might be another good option.

I will post final thoughts at the end of the season  - if I have any. But for now I would suggest that tubeless seems like a viable solution but don’t bother with the Dura-ace wheels. But just in case please refrain from passing me – because it is still an experiment.