Australian Cycling Forums - Bicycles Network Australia

I've got a new Schwalbe Ultremo DD to fit to my Mavic Kysrium Elites. So far tonight I've fitted the thing by hand twice. First time I pumped it up to 140 (max is 145) ... came up stairs... BOOM. I go down and it's popped off the rim.

Second time I try 130... this time I didn't even get upstairs before KABOOM! Same result.

I don't normally have trouble with tyres. Anyone got any ideas?

Can you video it next time and put it on youtube?

Why do you need to run 140 psi?

Nobody wrote:Why do you need to run 140 psi?

+1

More to the point, why do you need 140psi when it's sitting inside ?? Going by Sheldon's tyre pressure advice 130psi would be suited to a 100kg rider on 20mm tyres. Is that you?

More information including a 15% tyre drop chart at Bike Quarterly.

Schwalbe all seem to be an easy fit. I would suggest that you are likely to have problems with this tyre from now on. The bead is probably slightly stretched and hence the second time at a lower pressure.

Once I had an Ultremo R.1 blow away from the rim when I had Ksyrium Elites. My LBS guy said I hadn't seated the bead onto the rim effectively. He instructed me to fit the tyre and tube as per normal, inflate the tube to 15-20 psi where you can still use your thumb to manipulate the bead a little down under the rim lip, sometimes I could hear the bead snapping into place when I worked the tyre wall a bit. After working both sides of the tyre you gradually inflate the tube to desired pressure. I never had a problem with fitment on those rims or any others since that lesson. However, I was using 110psi in the rear and 100psi in the front with the ksyriums, unless you are on the boards I can't see why you want 140psi but that said the tyres should stay seated up to their rated pressure.

The only other logical thing I can come up with (assuming the wheel rim is not dinged) is if there is a minor manufacturing fault in the bead of the offending tyre making the tyre not able to clinch under the rim lip for a partial section of the rim......... maybe hard to pick up visually on a folding tyre like these.......

il padrone wrote:

Nobody wrote:Why do you need to run 140 psi?

+1

More to the point, why do you need 140psi when it's sitting inside ?? Going by Sheldon's tyre pressure advice 130psi would be suited to a 100kg rider on 20mm tyres. Is that you?

More information including a 15% tyre drop chart at Bike Quarterly.

Well with clothes, shoes, and stuff packed into the jersey pockets let's say I'm 80kg. With spares and a couple of water bottles lets say the bike is 10kg. According to the write up you linked that's 55kg on the back. That's pretty much 130 psi.

This tyre was a bit of an experiment. I've been running continental Force on the back. They roll **really** well but are worn out in less than 2000k. So, I thought I'd go for this schwalbe which is significantly heavier but should be more durable. I was hoping to up the pressure a bit to keep the resistance down. I'm now very concerned about the tyre.

I'll put another tube in it and try 120 psi this afternoon. Yes, I put 15 psi ish in it and rocked it on the bead to check the seating. Thing is I need to have confidence in the tyre.

My theory is that the tube should sit high in the tyre and push the beading down onto the rim. If the tube and tyre stick to each other (which they often do), the tube can push the beading off the rim . I coat the inside surface of the tyre with talcum powder so the tube can slide around easily inside the tyre. I also powder spare tubes I carry with me.

When you inflate the tyre, first inflate to about 20 psi and spin the wheel. If you watch the rim and tyre walls while the wheel spins you will see if it is properly seated or not.

I fitted that same tyre to the better half's bike with no problem at all. Run the rear at 110psi and 105psi on front. It's been a great tyre, rolls well and prevented a number of punctures. Operator error, I'd kindly suggest.

Never seen recommendations going up to 130psi. 115psi is almost the limit for heavies on road tyres. And a lot of rims/tyres don't even support anything over 120psi.

Comedian wrote:I've got a new Schwalbe Ultremo DD to fit to my Mavic Kysrium Elites. So far tonight I've fitted the thing by hand twice. First time I pumped it up to 140 (max is 145) ... came up stairs... BOOM. I go down and it's popped off the rim.

Second time I try 130... this time I didn't even get upstairs before KABOOM! Same result.

I don't normally have trouble with tyres. Anyone got any ideas?

Sounds like a fault in the tyre but that being said you've pumped it up way too hard. 120psi is really the absolute most you should run in a clincher.

For most clincher rims 120psi is the max recommended by the rim manufacturers.

jacks1071 wrote:

Comedian wrote:I've got a new Schwalbe Ultremo DD to fit to my Mavic Kysrium Elites. So far tonight I've fitted the thing by hand twice. First time I pumped it up to 140 (max is 145) ... came up stairs... BOOM. I go down and it's popped off the rim.

Second time I try 130... this time I didn't even get upstairs before KABOOM! Same result.

I don't normally have trouble with tyres. Anyone got any ideas?

Sounds like a fault in the tyre but that being said you've pumped it up way too hard. 120psi is really the absolute most you should run in a clincher.

For most clincher rims 120psi is the max recommended by the rim manufacturers.

it says 84-145 stamped on the tyre!

Mavic say 138 is their recommended max.

Comedian wrote:

jacks1071 wrote:

Comedian wrote:I've got a new Schwalbe Ultremo DD to fit to my Mavic Kysrium Elites. So far tonight I've fitted the thing by hand twice. First time I pumped it up to 140 (max is 145) ... came up stairs... BOOM. I go down and it's popped off the rim.

Second time I try 130... this time I didn't even get upstairs before KABOOM! Same result.

I don't normally have trouble with tyres. Anyone got any ideas?

Sounds like a fault in the tyre but that being said you've pumped it up way too hard. 120psi is really the absolute most you should run in a clincher.

For most clincher rims 120psi is the max recommended by the rim manufacturers.

it says 84-145 stamped on the tyre!

Mavic say 138 is their recommended max.

Yep and I run my rear at 120psi - but I have more than a couple of kilos over the rest of you

Like others already, they are easy to put on, seems you took due care whilst fitting it on. I've run mine at every bit of that pressure on Fulcrum 1's with no probs, you may just have a 'Friday' tire

Seems you are not alone ....

Schwalbe Ultremo ZX blow-up today

Mind you, the pressure you mention is way high imho. Even with 23c's, I have never gone over 110psi (and I was up to 98kg at the time). And now, I run 95/100 with the Conti Grand Prix in 24C and now being 88kg

MichaelB wrote:Seems you are not alone ....

Schwalbe Ultremo ZX blow-up today

Mind you, the pressure you mention is way high imho. Even with 23c's, I have never gone over 110psi (and I was up to 98kg at the time). And now, I run 95/100 with the Conti Grand Prix in 24C and now being 88kg

See my post above. I'm lighter than you, but according to the info in the bicycle quarterly that SB refers to I need to be running about 130 in the rear to have an optimum pressure.

We re-fitted it last night and ran it at 120 today. It hasn't gone KABOOM yet. We also used a continental race tube rather than a race light.

if you continue to have issues then you could try a wider tyre*, thus achieving the 15% tyre drop at a lower pressure.
*subject to the frame being able to accommodate the wider tyre.

Clydesdale Scot wrote:if you continue to have issues then you could try a wider tyre*, thus achieving the 15% tyre drop at a lower pressure.
*subject to the frame being able to accommodate the wider tyre.

The bike came with 700x25 but they didn't roll anywhere near as well as the Continental Force and Attack that I replaced them with.

Oh well... I'll just run them at 120. It's just a bit annoying when you buy a tyre that is placarded to 145 psi and put them on a rim where the manufacturer states 140psi and the tyre blows off it comfortably under both specified maximums. Oh well.

Given it has been bought as essentially a training tyre I guess I can handle a little more rolling resistance and enjoy a better ride. If it's as long wearing and as puncture and chip resistant as they claim then it will still be a good outcome.

Well last night I got an email from Ze Germans. Christian to be precise.

Anyway, he says it shouldn't blast off up to 290 psi!!!!! I'm going to send him some more info on it tonight but I suspect it was just something about the way I was fitting it. The only way to confirm this now is to blow it up to 140 (max for the rim) and wait a while. I might do that one time after a few beers to calm my nerves.

give yourself some margin, on a warm day/after a long decent with heavy braking will see the pressure rise noticeably.

Clydesdale Scot wrote:if you continue to have issues then you could try a wider tyre*, thus achieving the 15% tyre drop at a lower pressure.
*subject to the frame being able to accommodate the wider tyre.

Another option is to run the 23s you want on wider rims and therefore can run lower pressures. I've got Ribino Pros 23s that measure 24mm front, 25mm rear due to 17mm front, 19mm rear (inner) rims.

I took my race bike in for a service recently and when I picked it up they'd replaced the front tyre (Durano Plus) because it had started to delaminate on the sidewall. Apparently, Schwable wanted the tyre back to see what the problem was.

Perhaps a call/email to Schwable might be in order?

Comedian wrote:
it says 84-145 stamped on the tyre!

Mavic say 138 is their recommended max.

Maybe so, that'd be the ABSOLUTE MAX, NO SAFETY MARGIN. Pump it up to 140 and go ride in the sun for an hour or do a decent and you could quite possibly be looking at 160 psi and you're way into the danger zone for rim failure, tyre failure etc.. Leave a road tyre in your car parked in the sun up here and the pressure will go so high from heat expansion that the tube will have failed by the end of the day.

Manufacturers put these crazy max psi ratings on the sides of tyres I think in the hope that a punter will walk around a shop and pick one with the biggest max psi limit.

Even a really big heavy guy, 120psi is pleanty. I only run 100psi on our tandem and we are about 145kg (28mm tyres), if I was running 23mm tyres I'd put the pressure up to 110-120psi.

There is no benefit to running them at more than required and quite a few downsides to it.

Anyway I'm not saying that there isn't something wrong with your tyre - but you are pumping them up far too hard.

I like the schwalbe tyres and I’m sorry to read you had a problem with one of that breed, and yes I do think it is the individual tyre rather than excessive pressure.

For puttering around on the road I run schwalbe Lugano for a bit more puncture protection at 120 on the rear and 100 on the front. For the crits I use the schwalbe Stelvio’s 140 on the rear and 120 on the front without any problems all on cheap Shimano rims, and I weigh in at 96 kg.

I had the same problem once, turns out I hadnt taken the little valve nut of the valve, so every time i inflated the tyre it popped off the rim......

Ben

I run Conti GP4000s 23's on my commuter bike, and anything over 100psi is too harsh. I'm 80kg and carry panniers, sometimes with laptop and mains adapter within.

120psi ...