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Anyone running a tube inside a UST tire for racing ?

SCARY

Not long enough
Heard Warner taking about a couple guys doing this @WCs.I checked some older threads and am wondering if this has gotten to the point of just throwing a xc tube in and forget it.

Im thinking about running enve rims and am worried alittleoverahundred about how stiff they are pinching more easily.
Are the ust tires lighter or heavier than the regular Minions?I checked sick lines ,but am wondering if anything changed since 2009.
I run pretty high tire pressure usually,32-40 and hardly ever flat,but wonder if this would let me lower it a bit and not worry about flatting on such a stiff rim.

PS-OT . I ordered the 26" Intense Carbine frame for a Trailbike,I decided not to go 29r for no particular reason except the last trail bikes I had and never rode where more xc oriented.This one will be pretty aggressive and I think and set up more Enduro Am style.And...it's Carbon...and Red.
 

bengxe

Monkey
Dec 19, 2011
211
30
upstate NY
A couple months ago I flatted a tubeless converted EXO 3C DHF on the front, and had to replace it with a UST super tacky DHF and a DH tube. I couldnt get near the same level of grip, despite the softer compound. I dropped pressure until the tire was just flopping over, but never found a comfortable spot. Ive since mounted the UST minion up tubeless, but the problem is still there to some degree. The UST casing is too stiff, causing it to skip over bumps. My UST DHF is even heavier than my wire bead dh casing DHF, which is a better option with or without a tube.
Long story short, UST DHFs suck.
 

VMARTINEZ

Monkey
May 23, 2005
303
18
Ran a DHF none ust on some Enve AM 26 in wheels tubeless with no issues.
I am 224 and ran 35psi front and rear with no flats in the 2.5 months that I ran that setup.
The cool thing about the Carbine you ordered is that to convert it to 27.5 all you need is the g2 drop outs.
I spoke to Scott Sharples about that at Dealer Camp.
Good call.
VM
 

kidwoo

Artisanal Tweet Curator
Grab tubeless rims, fill up a tube with some stans, then throw the tube in.

You'll never flat but then you'll also never know if the tube was actually breached. If your navel gazing pondering the last few weeks here are any indication, that alone will make you lose a race.

Cuz you'll just HAVE TO KNOW!!!!!
 

tabletop84

Monkey
Nov 12, 2011
891
15
A couple months ago I flatted a tubeless converted EXO 3C DHF on the front, and had to replace it with a UST super tacky DHF and a DH tube. I couldnt get near the same level of grip, despite the softer compound. I dropped pressure until the tire was just flopping over, but never found a comfortable spot. Ive since mounted the UST minion up tubeless, but the problem is still there to some degree. The UST casing is too stiff, causing it to skip over bumps. My UST DHF is even heavier than my wire bead dh casing DHF, which is a better option with or without a tube.
Long story short, UST DHFs suck.
supertacky is not softer than 3c
 

Verskis

Monkey
May 14, 2010
458
8
Tampere, Finland
How do you seal the valve hole in the rim if you are using tubes? I guess it would leak even if the valve stem nut is tightened really hard. O-ring at the base of the valve stem inside the rim? But there should probably be some kind of flange on the valve stem to compress the O-ring properly.
 

Capricorn

Monkey
Jan 9, 2010
425
0
Cape Town, ZA
didnt one of the teams run a setup with wheels that had two valves, presumably to have a tubed fail-over incase the tubeless burped itself airless? Mavic/that team was very aloof when it came to questions about it. Somehow, mick hannah comes to mind. one rim, two valves...
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
A couple months ago I flatted a tubeless converted EXO 3C DHF on the front, and had to replace it with a UST super tacky DHF and a DH tube. I couldnt get near the same level of grip, despite the softer compound. I dropped pressure until the tire was just flopping over, but never found a comfortable spot. Ive since mounted the UST minion up tubeless, but the problem is still there to some degree. The UST casing is too stiff, causing it to skip over bumps. My UST DHF is even heavier than my wire bead dh casing DHF, which is a better option with or without a tube.
Long story short, UST DHFs suck.
You want a thin, not stiff sidewall so it folds when you ride? You are doing it wrong.



@Scary - If you don't flat I see no reason to do it. Maybe for race run only but maybe just run it tubeless with some stans and be done with it.
 

bholwell

Chimp
Mar 19, 2011
61
3
Knoxville, TN
didnt one of the teams run a setup with wheels that had two valves, presumably to have a tubed fail-over incase the tubeless burped itself airless? Mavic/that team was very aloof when it came to questions about it. Somehow, mick hannah comes to mind. one rim, two valves...
Maybe they were trying some variant of this: http://tubliss.com/ It's essentially a tire within a tire, so it requires two valve stems. I think it's a great idea, but the added weight is a big drawback.
 

sbabuser

Turbo Monkey
Dec 22, 2004
1,114
55
Golden, CO
Seems to me that would defeat the purpose of running tubeless, as the superfluous tube would have to be inflated enough to ride on by itself, right?
 

bengxe

Monkey
Dec 19, 2011
211
30
upstate NY
You want a thin, not stiff sidewall so it folds when you ride? You are doing it wrong.
Yea, somewhat. The thick, stiff sidewall of the UST tire plus the dh tube was stiff enough that it was hurting traction. A wire bead dh casing in the same compound grips much better for me.
 

'size

Turbo Monkey
May 30, 2007
2,000
338
AZ
How do you seal the valve hole in the rim if you are using tubes? I guess it would leak even if the valve stem nut is tightened really hard. O-ring at the base of the valve stem inside the rim? But there should probably be some kind of flange on the valve stem to compress the O-ring properly.
didnt one of the teams run a setup with wheels that had two valves, presumably to have a tubed fail-over incase the tubeless burped itself airless? Mavic/that team was very aloof when it came to questions about it. Somehow, mick hannah comes to mind. one rim, two valves...
was it a vital slideshow from ft. bill last year or the year before? i think it was slugger's or hannah's wheel they showed with the tube in a tubeless set up with the two valves. pretty sure they used some kind of epoxy/sealer to seal the tube valve to prevent air leakage if the tube did in fact flat and fill the tire.
 

steelforeel

Chimp
Dec 2, 2009
23
1
just drill a second valve hole, one for the tube and one for the tubeless valve
Yeah, but no matter how many new valve holes you drill it will still leak from the hole of the tubed valve?
I don't understand the purpose of running tube inside tubeless tire. Is the idea that if the tube punctures it leaks air into the tire? If you pinch flat a tube and the tire's still good and holds air, with tubeless setup you wouldn't have flatted anything.

I have same experiences as bengxe with Exo tires. Exo casing feels kinda more flexible than UST or 2ply and with same tire pressure you can have more traction as the casing conforms better or something. Just lower weight of the Exos might have something to do with the feel of better traction as well. Obviously risk of flatting Exo is higher.
 

S.K.C.

Turbo Monkey
Feb 28, 2005
4,096
25
Pa. / North Jersey
Yeah, but no matter how many new valve holes you drill it will still leak from the hole of the tubed valve?

I don't understand the purpose of running tube inside tubeless tire. Is the idea that if the tube punctures it leaks air into the tire? If you pinch flat a tube and the tire's still good and holds air, with tubeless setup you wouldn't have flatted anything. ...
Not necessarily. The tube acts like the butyl insert in Maxxis tires in that its purpose is to absorb energy and prevent the rim from compromising the outer wall (in this case the sidewall of the tubeless tire). That's how it's supposed to work on paper anyway. It depends on the hit the rim takes, the angle, etc. but SCARY was on the right track with Slugger's GT rig. Without getting into too many details, basically Slugger was running a FR or DH tube inside a tubeless tire setup.

Steel To understand the purpose of running this type of setup you have to look at it from a purely race-oriented point of view. On the World Cup level, pushing it as had as you can means that as a racer you must have confidence your bike will finish a race run. In other words, the purpose is to create a kind of "run-flat" system for the tires. It's the Navy rule of redundancy: "Two is One; One is None".

If the tube is breached, the tubeless setup will hold the remaining air and allow the rider to finish a run and at least put in a competitive time. Running this setup is much heavier than tube or tubeless alone but the trade-off is increased reliability.
 
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SCARY

Not long enough
I probably shouldn't drill holes in enve rims.I'm just guessing.I also don't see why it needs to be that much heavier than any other setup.I was just asking because of the stiffness of the enve rims.
Back in the day,I ran mag30 rims with Michelin tires.That was the absolute perfect set up if you wanted to get pinchflats.

Locally,I'm I little worried about running tubeless.We justhave too many sharp rocks.Maybe if I were in BC or a place with,like..dirt.
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
Yea, somewhat. The thick, stiff sidewall of the UST tire plus the dh tube was stiff enough that it was hurting traction. A wire bead dh casing in the same compound grips much better for me.
Sorry but that's just wrong. You had too much pressure but to be honest a 1ply tire with a lot of pressure isn't much better. Unless you think tire float = traction but that just makes me even more confused. Tire float on a 1ply tire will be worse but traction won't be better. Also who uses dh tubes?



@Scary if you are afraid about sing tubeless on enve because of rocks and rim stiffness maybe go with a tire from someone else than maxxis? Hutchinson seems to have upped their tire game and I remember their old tires being really bombproof (though 100-200g heavier than maxxis ust which are a bit lighter than 2ply's from them)
 

Tomasz

Monkey
Jul 18, 2012
339
0
Whistla
Okay, unless I'm missing something, then the purpose of running UST tires + tubes is to save weight by avoiding full dual ply, whilst avoiding the constant flats of EXOs, and yet retaining the reliability / non-finickiness of the good-ol-fashioned tube setup.

I was under the impression that such a setup is used by some racers, and have considered using the same setup myself. I think you could use something like the Schwalbe Freeride tube, which weighs in pretty light, and get away just fine. I've been running Schwalbe FR tubes inside of my 823 rim with 2.7" DHF front and back with zero issues at Whistler this season.

If you want to save a bit more weight, you could use super light tubes of course. Don't see why this would cause any issues so long as you're running sufficient pressure.
 
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bengxe

Monkey
Dec 19, 2011
211
30
upstate NY
Sorry but that's just wrong. You had too much pressure but to be honest a 1ply tire with a lot of pressure isn't much better. Unless you think tire float = traction but that just makes me even more confused. Tire float on a 1ply tire will be worse but traction won't be better. Also who uses dh tubes?
I wasnt asking a question, just saying what has worked for me. As I said before, I tried the tubed ust tire at everything from 35psi on down. Based on the thread title I thought my experience was relevant, guess I was wrong.
I run wire bead DHFs tubeless, the DH tube was all I had available at the time. And most of the resort bike shops around here only sell dh tubes, so apparently people use them.
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
Okay, unless I'm missing something, then the purpose of running UST tires + tubes is to save weight by avoiding full dual ply, whilst avoiding the constant flats of EXOs, and yet retaining the reliability / non-finickiness of the good-ol-fashioned tube setup.

I was under the impression that such a setup is used by some racers, and have considered using the same setup myself. I think you could use something like the Schwalbe Freeride tube, which weighs in pretty light, and get away just fine. I've been running Schwalbe FR tubes inside of my 823 rim with 2.7" DHF front and back with zero issues at Whistler this season.

If you want to save a bit more weight, you could use super light tubes of course. Don't see why this would cause any issues so long as you're running sufficient pressure.
You will get more float on a single ply tire. Going down in casing would make no sense in dh.

I wasnt asking a question, just saying what has worked for me. As I said before, I tried the tubed ust tire at everything from 35psi on down. Based on the thread title I thought my experience was relevant, guess I was wrong.
I run wire bead DHFs tubeless, the DH tube was all I had available at the time. And most of the resort bike shops around here only sell dh tubes, so apparently people use them.
Rethink your setup because something entirely else must be wrong here. I can see no reason why would a single ply tire would offer more traction.
 

bengxe

Monkey
Dec 19, 2011
211
30
upstate NY
There were no other changes, the tubed 2ply UST tire had less traction at all pressures than the tubeless single ply tire. Im not just talking about single ply vs dual ply, the dh tube made the biggest difference to traction. But the wire bead 2 ply tires work better than the UST 2ply tires for what feels like the same reason.
 

Lelandjt

Turbo Monkey
Apr 4, 2008
2,508
822
Breckenridge, CO/Lahaina,HI
I'm missing the point of all this. I run Exo tires on my AM bike and DH tires on my DH bike, both tubeless with the rims taped and Stan's liquid. I've had a couple flats from hard, sharp impacts* that tore a hole in the tire or severely dented the rim but every time it was a slow enough leak that I made it to the bottom of the run. The torn tires were patched with a standard patch kit and put back into tubeless service. The dented rims were straightened or replaced.

*Most of these were when I was running a little less pressure than normal due to not checking or experimenting. Learn what pressure you can get away with given your equipment and trails and check it daily.
 

SCARY

Not long enough
MY point.Not sure about everyone elses,was to have a system that has the best of both worlds.No burping,pinchflatting or weight penalty that might let you charge harder and not worry as much about ruining a race run,while using a (for me ) lesser tire pressure.

I just thought it was cool and wondering how doable it was.
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
There were no other changes, the tubed 2ply UST tire had less traction at all pressures than the tubeless single ply tire. Im not just talking about single ply vs dual ply, the dh tube made the biggest difference to traction. But the wire bead 2 ply tires work better than the UST 2ply tires for what feels like the same reason.
Maxxis ust sidewalls are less stiff than standard 2ply, not more so nope. Not for the same reason. Placebo?
 

atrokz

Turbo Monkey
Mar 14, 2002
1,552
77
teedotohdot
I'm missing the point of all this. I run Exo tires on my AM bike and DH tires on my DH bike, both tubeless with the rims taped and Stan's liquid. I've had a couple flats from hard, sharp impacts* that tore a hole in the tire or severely dented the rim but every time it was a slow enough leak that I made it to the bottom of the run. The torn tires were patched with a standard patch kit and put back into tubeless service. The dented rims were straightened or replaced.

*Most of these were when I was running a little less pressure than normal due to not checking or experimenting. Learn what pressure you can get away with given your equipment and trails and check it daily
.
The point of it is being missed here.

Faster DH racers/riders have caused tubless setups to burp out air in g-outs and hard cornering, causing flat tires in race runs. This was discussed a few times by Warner in this seasons Red Bull WC coverage, and isn't all that uncommon (some of us know this because we've ripped off a rear tire in hard cornering). While it might not happen on your local XC loop, it's very common to unseat a bead at a few G's in a corner when you're booking it. Do this with tubless (regardless of what sealant you're running) and you lose air. Simple as that.

So, most pros run tubes in the rear. This is a system that provides a layer of protection in case that tube flats.
 
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VMARTINEZ

Monkey
May 23, 2005
303
18
26" DH MTN Clincher 32 Hole -Rim Strip

But looking over the price list the AM rims are shipped with a tubeless kit.
So it may just be the Enve Rim Strip.
I can find out what they are doing and let you know.
VM
 

Lelandjt

Turbo Monkey
Apr 4, 2008
2,508
822
Breckenridge, CO/Lahaina,HI
The point of it is being missed here.

Faster DH racers/riders have caused tubless setups to burp out air in g-outs and hard cornering, causing flat tires in race runs. This was discussed a few times by Warner in this seasons Red Bull WC coverage, and isn't all that uncommon (some of us know this because we've ripped off a rear tire in hard cornering). While it might not happen on your local XC loop, it's very common to unseat a bead at a few G's in a corner when you're booking it. Do this with tubless (regardless of what sealant you're running) and you lose air. Simple as that.

So, most pros run tubes in the rear. This is a system that provides a layer of protection in case that tube flats.
If burping is the problem I'd think rim width and bead seat profile should be looked at.
 

atrokz

Turbo Monkey
Mar 14, 2002
1,552
77
teedotohdot
If burping is the problem I'd think rim width and bead seat profile should be looked at.
When you're hitting a berm at 40kph and hitting G forces high enough to bottom suspension, in a corner, it's not the seat profile that's the issue. They are just that fast and the forces pulling at the tire are just that high.
 

Lelandjt

Turbo Monkey
Apr 4, 2008
2,508
822
Breckenridge, CO/Lahaina,HI
When you're hitting a berm at 40kph and hitting G forces high enough to bottom suspension, in a corner, it's not the seat profile that's the issue. They are just that fast and the forces pulling at the tire are just that high.
Cars and motorcycles don't burp their tubeless tires and they see some high forces. Something can be improved here. I don't burp my tires cuz I run higher pressure than the factory guys. I can't afford to dent rims as frequently so I have to live with worse grip. Never burping is a nice side effect.

And yes, I'm just a little regional pro.
 
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fred.r

Dwangus Bogans
May 9, 2006
842
0
What pressures are you guys running with your UST set-up? I'm a big guy (240lbs before gear), running standard Maxxis DH tires (non-UST) w/ Stans and EX823s at 30f/35r PSI and hardly ever burp....
I wouldn't call myself slow but I'm nowhere near WC speeds... Either way I doubt most of you guys are either.
 
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