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I have an old Giant dutch bike and it has steel rims. Since I'm a big boy I felt that the 60PSI on the tyres is not enough and pumped my tyres to the maximum of 85PSI which is what my Schwalbe Marathon Plus tyres were supposed to be able to take in. It was great, riding was so much easier all of a sudden! Not the slowest guy on the road anymore, really fast if I wanted to in fact! I loved it.

Unfortunately a few days after I came to find one of the tubes neatly sliced. The tyre untouched. I wasn't sure what had happened but walked to work that day and planned to bring it to the workshop asap. When the day came I exited my house and found the other tube sliced in the exact same way.

no foul play involved!

I have meanwhile talked to lots of people. Some say it has to do with the steel rims even though I can't make any sense of that. I have also encountered people that said I just need the right tubes and tyres and it shouldn't happen anymore.

I'm now thinking of either buying a new bike, exchanging the wheels(which would be more expensive than the initial price tag of the bike) or give new tubes/new rimband and maybe different tyres a shot?

Does anyone have experience with this sort of thing or any sort of input?

this didn't help: Tire popping out of rim when inflating tube

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Nico
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  • What do you mean by tubes neatly sliced? The tire bead was blow off the rim like in the picture? If the rims are too small then this can happen (especially at higher pressure) - not really having to do with rims steel. – paparazzo Mar 02 '15 at 21:42
  • Thanks for your reply. Unfortunately I don't have a detailed picture of it, but it was sliced straight alongside the rims curvature. If there was a way to take out the tube and slice it with a knife all the way through alongside the curvature of the rim - it would've looked like that. One straight slit alongside the whole tube. I wouldn't say blown off, I'm still using the tyres, they appear fully functional. The rims themselves seem quite wide, could it occur if the tyres weren't wide enough? – Nico Mar 02 '15 at 21:48
  • Very simple question. When you found the tire flat was the tire bead inside the rim or not. In the picture the tire bead is outside the rim – paparazzo Mar 02 '15 at 21:50
  • Ok, I'm a noob but this is what it looked like when I found my bike. So I guess it was blown off the rim! – Nico Mar 02 '15 at 21:51
  • Answer updated from comments. – Deleted User Mar 02 '15 at 21:55
  • I suspect that you have the wrong size tires. If those are 26" tires, in particular, then you cannot just put any 26" tire on the rim, but must determine which 26" "standard" was used to make the rims. – Daniel R Hicks Mar 03 '15 at 14:24
  • Also, I have seen something similar on bikes left out in the hot sun for 30-60 minutes. The heat causes the tire to expand unevenly and can lead to it popping off the rim. (Very rare, but it happens.) – Daniel R Hicks Mar 03 '15 at 14:27
  • Actually they are 28". They did pop in summer. – Nico Mar 03 '15 at 16:35
  • There are at least two different "bead seat diameter" values for 28" tires -- 622mm and 635mm. A 635mm tire on a 622 rim would appear to fit but would be prone to the failure you see. Look on the side of the tire for a 622-nn size or a 635-nn (where nn is the tire width). The old and new tires should match in that first number (the second is not so critical). – Daniel R Hicks Mar 04 '15 at 03:13
  • The tyre is a 622. How can I find out what the rim is? Just measure it with some tape? – Nico Mar 04 '15 at 10:51

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OK if the tire was blown off the rim then I highly suspect that is the whole story.
When the tube leaks out the because tire bead has come out the tube will burst and you will see a slit.

A tube outside a tire cannot take much pressure.

Most likely when you went from 60 to 85 psi it was enough pressure to push the tire off the rim (bead).

I have seen this with some older bikes. The rim is a little small.
Look for tires that run small and run at lower pressures.

You might also have a mismatch like a 27 on a 700c.

A Schwalbe Marathon Plus is a pretty hefty tire and tend to fit a little tight so this is kind of strange. But it did happen after you went to 85 PSI. Maybe give it a try again at 60 PSI. Even if you get a new bike you would have this as a backup.

paparazzo
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  • How big are you? If you have a larger tire then you might get away with less than the maximum pressure. – paparazzo Mar 02 '15 at 22:01
  • The biggest guy to ride a bike you've ever seen possibly. Haha. I'm like 6´5´´ and well past 300 pounds. haha. That's basically why I'm desperate for more pressure. – Nico Mar 02 '15 at 22:02
  • OK then maybe look for a bike that takes up to 38mm tires. Or even a touring that takes 45. The marathon comes in a 700 x 45. Or even go to mtn bike for 2.25. – paparazzo Mar 02 '15 at 22:06
  • Everything else the same a 45mm at 70 psi has about 15% more weight bearing capacity than a 38mm at 85 PSI. – paparazzo Mar 02 '15 at 22:17
  • Ok, that sounds reasonable. So it looks like I'll have to go with a new bike if I want less rolling friction. The thing is that I really like the riding position and style of a dutch bike. I had looked at Koga bikes at some point but after all I don't want to spend that much. Any recommendations in that sector? – Nico Mar 02 '15 at 23:01
  • I am US but here like Surly Troll. And the bigger tires are not going to give you less friction. But they will give you more weight bearing. A Kona Big Rove is maybe more than you want to spend but well past 300 pounds a cheap bike is just going to have trouble. – paparazzo Mar 02 '15 at 23:22
  • Yeah, that's the thing. I mean the bike does the job, it was just much nicer with higher pressure. Thanks for the recommendations. The UK bike market is a little weird. Some brands from the mainland are really hard to get by for some reason. I did test ride a Pashley Sovereign Roadster over here which is a massive bike but the riding position was a little awkward and the breaks were kind of bad. There's also a brand called Dutchie who sell kind of cheapish dutch style bikes, I have an offer for a Dutchie Drapper 3 Speed at the moment. I'm certainly not a typical cyclist... – Nico Mar 02 '15 at 23:26
  • You don't necessarily need to get a new bike. Have a shop asses the details of your rims, as there may be good tires that will be a perfect fit. – whatsisname Mar 03 '15 at 22:52
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You had the tyres inflated to their maximum pressure and, in a comment, you say you'd left the bike outside in the summer sun. I'd say it's very likely that the tyres got hot, which increased their pressure beyond maximum and blew the tyres off the rim. As that happened, it would have exposed a gap between the tyre and the rim through which the tube would have burst.

If that's the case, there was probably nothing wrong with the tyres, tubes or rims per se, but circumstances conspired against you. Keep the bike indoors if possible or, at least, in the shade.

David Richerby
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Find what caused the flats. Take the tube out, keep it relative to the tire and find out where the hole is. Search that area of the tire or rim to find the offending object or hole.

There are a great many possibilities, your rim strips could have gone bad and rotted away, leaving your nipples or spokes exposed. One of your spokes could be over tightened and sticking past the nipple. You could have a piece of glass (or other sharp object) embedded in your tires. Steel rims in and of themselves are not bad. They don't magically make flat tires any more than any other rim material. However, steel rims tend to be older, and old wheels tend to have issues (like maladjusted spokes or rotted rim strips).

From you additional info, it's highly possible the beads on your tires are weak and/or the rim surface isn't providing good purchase for them. It's possible that the bead "let go" from the rim and the tube simply blew out the exposed are (much more likely at higher pressures). Generally this is accompanied with a loud bang similar to a gunshot.

Deleted User
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  • Thank you very much for your reply. This actually happened to me in summer and since then I've been riding with 60PSI and I haven't had anything since then. Not even a puncture. At the time the tubes were literally sliced straight alongside the rims curvature. This happened when the bike was standing in front of my house and it happened to both tubes independent of time in the same way. Which makes me believe that it's not very likely to be a little detail like the ones described by you. It seems unlikely given the circumstances and way they were sliced. – Nico Mar 02 '15 at 21:44
  • I am not clear on what you mean by "alongside the rims curvature" Was it on the outside surface (tire facing), side surface (tire bead facing) or inner surface (rim strip facing). Anything you have which is "vaguely" sharp (nipples, exposed bead, etc) is more likely to cause punctures at higher pressures. – Deleted User Mar 02 '15 at 21:51
  • I'd say rim strip facing but it is hard to say since all that was left was the limp remainders of the tube. Wouldn't know about the gunshot sounds since it stood in front of the house. – Nico Mar 02 '15 at 21:53
  • Higher pressure asks for quality rim strips. Check for wear. Replacing the pair is a good option since they are not that expensive. Make sure, the ones you get are wide enough to cover the nipple-holes as much as possible. – Carel Mar 03 '15 at 12:58
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Overinflation blowout is a possibility; I had that happen with Schwalbe Marathons, don't recall the exact PSI but it was the tire's rated max.

Try 10 under the max; if that does okay, then maybe push it a little further.

D.Salo
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