Wednesday, October 8, 2008

Holy Grail CX Wheel/Tire Setup?

(Note that I am following the Rev's suit and playing off a religious theme.)

Over the course of my short CX career I've battled with wheel and tire choice. In 2006, when I first started racing CX, I showed up at the RMR with some Ritchey cross tires inflated to 75 PSI. The roadie mentality is fill 'em up, and I did, all the way. While warming up, I blew one of the tires right of the rim, breaking the kevlar bead at the same time. Not knowing that lower pressure is better, I promptly put on my spare wheel with a Kenda tire, also inflated to 70ish PSI. That race was a bit of a blur, but I do remember slip sliding all over getting jarred by the hard ride, and crashing several times -- not that the tires had anything to do with it.

Over the course of the 2006 season, I also experimented running Stans system with Ksyriums, standard box rims, and a variety of tires. I eventually gave it up, but not after I had tried packing tape, Stan's strips, split BMX tires, voo doo, and after I had blown a couple Kenda tires off the rim, ripped out the kevlar beads, and burped some Muds (while winning a race -- twice). Oh yeah, since Bart seemed to have luck with his Stan's setup I asked him to lick my wheels; unfortunately it didn't help.

Not completely learining my lesson in 2006, I made a run at using Stan's in 2007. The benefit of Stan's (in theory) is that you can run low pressure without pinch flatting and have protection against goatheads, of which there are many on all Utah courses. Needless to say, my attempts at using Stan's failed, and I raced on Muds, tubes, and Ksyriums.

Not completely learning my lesson in 2006 and 2007, I made yet another run at using Stan's. And guess what? It worked . . . or seems to be working.

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Reynolds DV UL with Challenge Grifos on the left (4.4 lbs), Reynolds Mid-V Clincher with Hutchinson Bulldogs on the right (5.3 lbs) -- (and a trick Edge KOM on the far right, but that's another story)

Two key factors have changed. I'm not using Ksyriums and I'm not using Michelin, Kenda, Ritchey, or Maxxis tires. Instead I'm using some Reynolds mid-V clinchers and Hutchinson Bulldog CX tubeless tires. Using the Reynolds over the Ksyriums means that I have a tight tire fit. Tires are really hard -- bloody knuckle hard -- to get on the Reynolds rims. They are so tight that I was able to air up the tires without an air compressor. Because there is a tight tire fit on the rim, it's hard(er) to burp the sealant and air out. Using the Hutchinsons over other tires means that I have a better, beefier, and more flexible bead, which also prevents against burping and ensures a good seal. My hope is that the bead is also stronger and will not spontaneously self destruct.

So, today, running below 30 PSI (I could push the tire to the rim quite easily), as I was rallying (to the extent I can do so) through soft dirt, bark, and off cambered grass WITHOUT BURPING or air loss, I wondered whether I had discovered the holy grail wheel setup -- especially after I picked out several goatheads from my front tire and the holes immediately sealed up. Those thorns can make tubulars really frustrating and expensive (Grifos have latex tubes in them that don't work well with sealant).

But, having given it further thought, there are two things that stop me from actually declaring that this setup is the holy grail wheel setup: weight and suppleness. Compared to a DV UL with Challenge Grifo setup (without sealant), the Reynolds Clincher Hutchinson setup (with sealant) weighs nearly a full pound more. That's a lot of rotating mass. While it probably wouldn't make a whole lot of difference to a fast guy, it might (at least in my mind) mean the difference between a mid pack to a back-of-the-pack finish. Like that should matter anyway. Though somewhat of a secondary point, the tires are less supple than tubies. The sidewalls fold at low pressure and hard cornering is a bit squirrly. That's at really low pressure -- I shouldn't complain because it's amazing that the tires can be run at tubular pressures.

The huge advantage of the clincher setup is that they self-seal, you can get 6 clinchers for the price of 2 tubies, they are easy to mount, and they won't roll off the rim. And like tubies, you can run them at low pressure without pinch flats.

Holy grail? Close, but as is the case with most things in life, there are trade-offs. I'm just happy that after 3 years, the Stans isn't blowing out all over the place.


Team Rico said...

time to throw down for some tubies with Dugast rubber. They are worth every penny!!

Faceless Ghost said...

I think you overestimate the effects of weight. One pound is less than half a kilo. In cyclocross, that weight is only going to matter during hard accelerations. At 20 watts/kilo, that pound would cost you less than 10 watts. And how often do you accelerate that hard during a cross race? I guess the weight will slow you down. But I don't think it will slow you down noticeably, and it won't slow you down as much as a flat tire.

By the way, I think the link to your picture is broken.

Jared said...

what pressure do you run your $Dugasts$ at? . . . Remember, all it takes is one goathead, unless you are good at removing glued tire, removing basetape, removing thread, removing portion of tube, patching, reinserting portion of tube, resewing, reguling basetape, remounting and glueing tire . . . I nearly bonked just typing that out.

Lots of accelerations in CX races. You should come race just to confirm! I forgot to mention that the Hutchinsons are 2mm wider, so you get some extra rubber.

Daren said...

I've got Grifos with about a cup of Stans in them. It doesn't add much weight and gives some puncture protection. Rico, Chrispy and I did a bunch of reading and found Stan himself emphatically states Stans will not harm the latex tubes in high-end tubies. We all now have Stans in Grifos and Dugasts.

However, you still can pinch flat a tubular so that the sealant won't repair it. I did so at Ogden.

Tanner and I both ran Mich. Muds with Stan's rim strips at Draper with no problems. I wanted a little more goathead protection after getting about 15 the night before the race.

JZ said...

I have had success so far this season with MAxxis Raze tires mounted ghetto tubeless (split mtb tube) on some Bontrager Race Lite wheels. I am running them around 40-45 psi in the front and 45-50 psi on the rear (I do weigh 180 lbs). It is a little scary because they are real easy to mount even with the extra tube there. I have tried really hard to get them to burp, roll off, etc. and so far so good. One race with no problems.

I have loved the Hutchinson Road Tubeless tires, so may try some Bulldogs when I need new tires.

I am with Faceless Ghost on the weight thing. It may slow you down a few seconds per race (and that is not accounting for other factors, including gained momentum once up to speed, etc.), but that is hardly moving you from mid-pack to the back of the pack.

Eat Sleep MTB said...

So what exactly is your wheel budget? I don't think we work from the same spreadsheet.

Jared said...

gee thanks for shooting me down on the weight thing, I like to have some sort of excuse. . . .

so as to dispel speculation that I'm a spendthrift, let me disclose the following:

Reynolds DV UL -- purchased at or below wholesale; admitedly still shelled out a signficant amount of coin; 3 yrs old

Reynolds Clinchers -- straight across trade with the Claw for some Ksyrium tubulars, which were purchased for cost or less

Edge Wheel -- nothing paid, not even mine, just an ornament in my living room

JZ said...

Jared, I don't mean to be completely dismissive of the weight thing. I have switched back and forth between a heavier and lighter wheelset on two different mountain bikes this year and it really is interesting to feel the difference in how the bikes ride and other than bombing a downhill, I always prefer the lighter wheelset. I think it is less of an issue in a normal cross race, but hey every pound counts eventually.

So, you have made me curious about all your experience with tubeless set ups. Do you think I am playing with fire with the Raze Ghetto Tubeless set-up? I have been running ghetto tubeless on my mtb with absolutely zero problems, but cross is a different beast.