Track Cycling: Velodrome Racing and Training Area - Overinflating tubulars/tubulars in clincher rims

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flesh_pile
06-12-08, 03:45 PM
So here are my options/questions/dilemmas with a little bit of background info. After putting two track days behind me, I'm thinking about wheel/tire choices. Here is what I have available to me for the front wheel:
1. Aerospoke tubular wheel with glued Continental Sprinter (170psi max, measures 23mm)
2. Real Desing Supersonic clincher (60mm deep rim) with latex tubes and Michelin Pro2 Lights (115psi max, 23mm - measures 24mm)
3. Unused/unmounted Veloflex Record (145 psi max, measures 20mm)

Here are my questions:
1. What can happen if you overinflate tubulars? There is no rim for it to blow off of. Does it just explode out of the casing? I have heard that there is probably a 50% safety margin built into the max psi of most clincher tires for liability reasons so I'm assuming the same holds true for tubulars. I've been running 130-140psi in my 115psi Michelin clinchers with no issues the past two weeks.
2. Could I run my Veloflex Records at 145+ psi in my Real Design rim? I know rims probably have a max psi rating before they break but the tire is so narrow and contained anyway as it's a tubular I couldn't see any adverse effects from the tire pushing out the rim a tad. The only thing that I could see would be some adverse reaction on the tire itself as the bead of the rim pushes into the tire. I've been stretching my Record on a clincher rim this past week in anticipation of mounting it on a true tubular rim at some point in the future and it seems to be working fine now. I have not ridden on it but I can't see why or how it could fall out of the rim - it's in there pretty deep and will require tire levers to get it out.
3. What setup would you recommend? The Pro2 Lights/latex have the lowest rolling resistance compared to the others at the same psi, but the tubulars can go to higher pressures and negate this savings. Plus the tires are pretty wide compared to the tubulars. The Real Design rim shape is more aero than the Aerospoke rim but it has spokes that stick out into the wind while the Aerospoke only shows the width of the tire to the windw. I would think at the 0 degree yaw angle that I'd be racing at the benefits of both would probably cancel each other out.
By the way, I do not want to take off and reglue the Record tire on the Aerospoke as of right now.

Thoughts?


flesh_pile
06-12-08, 03:56 PM
I'm 195 pounds and ride at the Valley Preferred Cycling Center at Trexlertown (formerly the Lehigh Valley Velodrome) which has just been resurfaced with concrete. For those who haven't seen it, here's where I get my rolling resistance data:
http://biketechreview.com/tires/images/AFM_tire_testing_rev7.pdf
As you can see, the Michelin is one of the lowest RR but aerodynamically might suffer due to it's width. It is also well used. The Veloflex is new (a ding against it's already higher RR) but is more aero and can go up to a higher PSI. If you look on the last page you can see that higher PSIs do in fact lower RR a decent amount. The Continental is used as well.

queerpunk
06-13-08, 06:23 AM
Wait. You want to run a tubular on a clincher rim? Why would you want to do this? Do you honestly think that's the best option? I don't. I've never heard of anybody doing that. I'll be proven wrong if somebody else wants to chime in, but it sounds like it could be a recipe for disaster.

I recommend the Real Design rim with these Michelin Pro2 tires of yours. Here's why - it's a pretty good quality clincher, which is going to be far superior than praying that a tubular stays on your clincher rim, or, for that matter, using the AeroJoke. Which, since you're into data, is not very aerodynamic (nor is it stiff, and a sturdy front wheel is what I like under me at the track). It's just heavy.

I also recommend starting out by focusing on your skills on the track, not what gear will make you go faster. Ensuring that you're well fit on the bike and that you're comfortable holding your line in a sprint, or riding in a close pack on the banking, is going to be far superior than worrying about rolling resistance or about the aerodynamics of a tire that's a few millimeters wider.

It's natural to start thinking about gear, but it's the engine, after all. Ride what you got and remember that there's no need to buy your way to the top - yet.


dutret
06-13-08, 10:24 AM
- aerospokes are heavy, flexy and not very aerodynamic what you have is probably better.

Is the real design even available as a track wheel? I really doubt it's worth taking a set appart to canabalize the rims. Either way you can't run tubulars on it(with the exception of tufos tubular clinchers).

How high do you want to inflate your tires? What track are you riding on? For most in the states 130 is about as much as you'd want. Tubulars have other benefits and it's likely if you use hard glue the rolling resistance advantage of clinchers is negated. I wouldn't worry about it though. If you don't need wheels right now just ride what you have till you can afford something decent. If not get reflex/formulas and use tubulars. Don't worry so much about rolling resistance either.

zzzwillzzz
06-25-08, 09:10 AM
i've used a tubular on a clincher rim, but that was only because i ran out of tube and patches. i was able to get home after riding 30 miles this way. it's for an emergency situation only on the road and there's absolutely no way you could use this setup on the track as you have to take corners and downhill very slowly to not roll the tire off the rim.

you don't want to overinflate your tires, that just raises the rolling resistance.

your only viable option of the choices you've given is to run the deep clincher for the front. what types of events are you planning on running?

Yoshi
06-25-08, 12:11 PM
you don't want to overinflate your tires, that just raises the rolling resistance.

Over-inflating decreases rolling resistance. That's one of the reasons people use them. What you might be thinking of is that tubulars usually have more rolling resistance than a comparable clincher inflated to the same pressure. But tubulars can be pumped up much higher.

zzzwillzzz
06-25-08, 05:27 PM
Over-inflating decreases rolling resistance. That's one of the reasons people use them. What you might be thinking of is that tubulars usually have more rolling resistance than a comparable clincher inflated to the same pressure. But tubulars can be pumped up much higher.that's not what i've been reading recently

ultraman6970
07-03-08, 02:03 PM
???? Where u have read that??? U can over inflate tubulars but the problem is that theyget so hard that will pop with almost anything. I bet u dont want to get flats right?? Tubulars have better rolling than clinchers eventhough I have riden in the road some clicnhers that ride similar to tubulars. In the track with Clinchers??? Nah... u wont get the same fast rolling using clinchers and no matter how much u inflate those clinchers they wont get hard enough as a tubular.

Regarding a tubular in a clincher rim?? well u can put that thing in there as yoshi said but from there to use them for racing no way!!!... what u can do is to put a Tufo TUBULAR CLINCHER in a clincher rim w/o any problem. They ride fine anyways.

For track racing and road racing tubulars is the way to go... no matter what other people think... ones u have used tubulars is hard to come back to clinchers... too much difference...

Good luck. :)