Sunday, September 4, 2011

Tubeless Cross.

For my trek to RI back in July I built up a set of clinchers. My reasoning was two-fold.
First since I would be riding solo for a long distance on unfamiliar roads I wanted to be easily repair multiple flats, with minimal additional gear (i.e. not having to carry more than one extra tubular, being able to patch a tube if I got numerous punctures), and secondly the idea of having a wheelset to try tubeless for cross was appealing.

I had tried tubeless in the past with the same rims without success.  This time around I used Velox rim tape and smaller tires to give me a tighter fit.

The front tire aired up and locked into to the bead in text book fashion; Stan should have been taping my successful attempt.
The rear was trickier.  It would air up, lock in, and then  quickly bleed off pressure until flat.  No matter how much shaking and spinning I tried, it wouldn't seal.  Finally I found the problem was the tight tire bead had folded over the Stan's rim strip for about 3" preventing a perfect seal.   After digging it out I added more sealant than I'd typically use in a 29'er tire just to be sure.
Results =  Victory!

Going tubeless over tubular was going to cost me a solid half pound of rotational weight.  But with that half pound I gained a stiffer wheelset (my tubulars are Mavic Gel280s and Mavic GL330 rims), and the ability to more easily and quickly change my tires.  I have never been able to air up tubeless tires with a floor pump and still can't, so I won't be changing any tires trackside, but I can easily do so the night before.

Initially I was thinking maybe I'd train on the tubeless and race on the tubulars, but after today's ride I think the tubeless wheelset wins.  Being a smaller guy, wheel stiffness has never been top priority, but once I hit the trails the advantage truly became apparent.   I never realized how much stability I was giving up with my vintage rims.

I have had good results with not flatting tubulars.  I run sealant in them and have yet to puncture (knock wood!).  Considering where I train, and how with clinchers and tubes I would typically get at least a flat a ride, I was pretty happy with that.  With tubeless I get the same level of flat prevention, but also the ability of just throwing a tube in in case the unmentionable does happen.  The tubeless setup proved it's mettle today as I bombed a rocky fireroad and at the bottom came upon a group of about 8 riders from one of the local clubs who had just had multiple flats on the same descent. 
On another descent I kicked up a huge rock launching myself skyward, landing with enough force to dislodge my securely strapped pump.  The results?  Absolutely nothing.  Not a squirt of air or sealant escaped.
I was running my pressure on the higher side (45 psi), because I spent about 1/3 to half of my ride on tarmac, but I'm excited to test lower race pressure on Tuesday.

Now the question still remains, with an SS class in all the races currently listed for Connecticut, do I leave it a 1x9, or go back to what I know best?

1 comment:

Alby King said...

Racing SS results in a mixed evaluation: Beat some gearies "I must be super bad". Lose against gearies "well, ya see - I'm running SS"

It all depends on your motivation. I say change it up and roll geared to properly compare dick size.

Of course when I ride alone for pleasure, I prefer SS.