Yet Another Cycling Forum

General Category => Freewheeling => Topic started by: Rhys W on 02 April, 2011, 09:00:47 pm

Title: "We've got a tube but it's the wrong size"
Post by: Rhys W on 02 April, 2011, 09:00:47 pm
On our ride today we encountered a couple of mountain bikers standing around at a junction with a main road. We made small talk as we waited for the rest of our group to get to the top of the climb - they'd punctured. They didn't seem to be doing anything about it so I asked "do you have a spare tube?", which resulted in the subject line  ???

They said it was the "wrong width". We reassured them that even if it was not optimal, it would suffice to get them home, tubes are designed to fill a range of tyre widths etc but they were having none of it. Apparently it didn't match the 2.1" or 2.2" marking on the tyre so it wouldn't do. Hell, I'm sure my 700c x 18-25 spare would do the job. No go - they were phoning for a taxi to get home. Not sure how the cabbie would feel about a muddy MTB in the back of his cab...

The scary thing was that they were preparing for a 100-mile charity ride. On the road, with Carrera near-BSOs. Is there any excuse to be this clueless, what with the internet and that?
Title: Re: "We've got a tube but it's the wrong size"
Post by: Arch on 03 April, 2011, 10:30:14 am
Not even carrying a repair kit?  But wouldn't know how to use it anyway by the sound of it.

 :facepalm:
Title: Re: "We've got a tube but it's the wrong size"
Post by: Steve Kish on 03 April, 2011, 10:31:06 am
Unfortunately there are still some out there that buy a bike and end it there.

A few weeks ago my CTC Old Thames Valley Gits group met a chap by Boulter's Lock in Maidenhead who was pushing his nice carbon Spesh with a flat front tyre.  Of course, he was wearing carbon shoes with Look-style plates, so waddling was the order of the day.  Walking to Marlow, at least 5 miles away! :o

We chatted; he had no spare tube, no pump, no tools whatsoever.  We took his tube, sorted the puncture with a Park patch and listened to his excuse that he was just using cycling as a form of cross training because he was actually rower. :-\

FWIW, my MTB uses winter 26 x 2.35 tyres and 26 x 1.9/2.1 for the summer.  In either case, all my spare MTB tubes are 26 x 1.3, as I can get two of these into my bottle cage spares tub rather than just one fat one.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Biggsy on 03 April, 2011, 02:16:27 pm
I'd rather knit my own tube from beetles than call a taxi.
Title: Re: "We've got a tube but it's the wrong size"
Post by: tatanab on 03 April, 2011, 02:21:27 pm
Unfortunately there are still some out there that buy a bike and end it there.
True, even in "cycling" countries.

About 20 years ago I was on tour in the hills above Lake Annecy.  I passed a mountain top cafe which was obviously a turning point for local riders out for a quick climb.  A couple of miles into the descent I came across a rider standing at the side of the road with a flashy machine and in full flashy kit, so I stopped.  He had a rear wheel puncture and had a spare tube and levers but no pump, so I offered him mine.  It did not help because he did not know how to remove the wheel, let alone take a tyre off, so I ended up doing the job for him.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Arch on 03 April, 2011, 03:12:57 pm
I'd rather knit my own tube from beetles than call a taxi.

There's always the 'stuff it with grass' option....*

On an MTB with knobblies, I'd have thought you could ride a fair bit on a flat tyre, if you put your mind to it. My winter hack has Big Apples and they will function at very low pressures (yes, I'm rubbish at maintenance).

*Actually, I'd have thought that with a bit of searching you'd find enough plastic bags and random polystyrene in most roadside ditches to effect a stuffing of some sort.
Title: Re: "We've got a tube but it's the wrong size"
Post by: pcolbeck on 03 April, 2011, 03:25:13 pm
FFS I've used the wrong size tube on a motorbike before to get me home never mind a push bike.
Title: Re: "We've got a tube but it's the wrong size"
Post by: arvid on 03 April, 2011, 03:45:49 pm
I once (badly) fitted a wrong sized tube, and it exploded about 5 minutes after I put the right amount of pressure in it. This tube was too big for the tyre. I think it got me the 5km home with low pressure though, but it had a quite bad wobble.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Biggsy on 03 April, 2011, 03:54:50 pm
I once (badly) fitted a wrong sized tube, and it exploded about 5 minutes after I put the right amount of pressure in it. This tube was too big for the tyre. I think it got me the 5km home with low pressure though, but it had a quite bad wobble.

That was just coincidence or because you didn't tuck it in completely.  A big tube doesn't put any more force on the tyre than a normal one does, or make it any bigger - the tyre being a rigid thing compared to the tube.
Title: Re: "We've got a tube but it's the wrong size"
Post by: itsbruce on 03 April, 2011, 04:00:18 pm
[He had a rear wheel puncture and had a spare tube and levers but no pump, so I offered him mine.  It did not help because he did not know how to remove the wheel, let alone take a tyre off, so I ended up doing the job for him.

FFS!  Nobody ever showed me how to take a wheel off; I looked at how it was attached and worked it out for myself.  It really isn't rocket science.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Kim on 03 April, 2011, 04:12:30 pm
I once (badly) fitted a wrong sized tube, and it exploded about 5 minutes after I put the right amount of pressure in it.

Same.

Though it was a 26" tube in a (thankfully reasonably chunky) 700c tyre, which is always going to be a bit fiddly.

I now have tubes of all three relevant sizes permanently installed in a pocket of my rack bag in case I swap it between bikes without thinking again.  And a spare tube cable-tied to the frame of my hybrid, because that's the one I tend to jump on without thinking about tools and spares.


Not carrying tubes and tools is understandable, at least for utility cyclists or people out with the kids on BSOs who don't really know what they're doing.  It's not carrying a pump that baffles me.  With MTB-ish tyres, especially the slime-filled variety, an awful lot of punctures are slow enough that you can get yourself home by putting a bit more air in every mile or two.   :facepalm:
Title: Re: "We've got a tube but it's the wrong size"
Post by: Biggsy on 03 April, 2011, 04:20:29 pm
I tend not to bother with a pump when going only a couple of miles on Marathon Plus tyres :smug:
Title: Re: "We've got a tube but it's the wrong size"
Post by: TimO on 03 April, 2011, 04:36:08 pm
... It really isn't rocket science.

Even if it was, that wouldn't worry me. ;D

On my commute I'll carry two spare inner tubes (to suit whichever bike I'm cycling), a pump, a CO2 inflater, and a puncher repair kit.

On a longer ride, like a FNRttC, I'll often carry more inner tubes and CO2 cartridges, and occasionally a spare tyre.  I've used all of them on one occasion or another.

My record for punctures is three in a commute, on two different occasions, probably a decade apart.  Generally these days the better tyres that I use make punctures much rarer, but the last triple puncture trip was about 18 months ago (with a damaged, and compromised Marathon Supreme).

I've always known how to get a wheel off, and repair a puncture.  I'm much more practised at it now, and can get most tyres on without having to resort to mechanical aids, but I do have a tool for those extra tight racing tyres that can occasionally cause problems.

In an emergency most combinations of inner tubes and tyres will work, the exceptions being too extreme disparities in diameters (eg a 700C inner tube in a Brompton tyre), a smaller inner tube than the tyre, and a very extreme range between small inner tube width and large tyre width (although I'd try that at low pressure if I had no other option).

It's amazing that people can't deal with such an easy repair, but then again many people can't deal with a flat on a car, and that's generally easier than one on a bike (in my limited experience).  Many cyclists don't seem to have grasped that rear LED lights occasionally need new batteries either, and seem to assume that they're designed to last the lifetime of the bike, so it's not a unique class of problem. :-\
Title: Re: "We've got a tube but it's the wrong size"
Post by: Gattopardo on 03 April, 2011, 04:40:12 pm
Unfortunately there are still some out there that buy a bike and end it there.
True, even in "cycling" countries.

About 20 years ago I was on tour in the hills above Lake Annecy.  I passed a mountain top cafe which was obviously a turning point for local riders out for a quick climb.  A couple of miles into the descent I came across a rider standing at the side of the road with a flashy machine and in full flashy kit, so I stopped.  He had a rear wheel puncture and had a spare tube and levers but no pump, so I offered him mine.  It did not help because he did not know how to remove the wheel, let alone take a tyre off, so I ended up doing the job for him.

So he didn't have to get his hands dirty.........noot I have an idea.
Title: Re: "We've got a tube but it's the wrong size"
Post by: hellymedic on 03 April, 2011, 05:08:16 pm

Not carrying tubes and tools is understandable, at least for utility cyclists or people out with the kids on BSOs who don't really know what they're doing.  It's not carrying a pump that baffles me.  With MTB-ish tyres, especially the slime-filled variety, an awful lot of punctures are slow enough that you can get yourself home by putting a bit more air in every mile or two.   :facepalm:

Pumps get nicked. I never got on with mini-pumps.
(Not that I'd go out without a pump; I understand those who take the risk or have theirs filched.)
Title: Re: "We've got a tube but it's the wrong size"
Post by: Arch on 03 April, 2011, 05:17:14 pm

It's amazing that people can't deal with such an easy repair,

What's more amazing to me is that the couple of cyclists who were clearly inexperienced, refused to accept the opinion of a group of riders who presumably clearly knew what they were talking about.

I wonder if they were embarrassed that they had a tube but didn't know how to replace it, so pretended they thought it wouldn't work to avoid looking incompetent.

And if they think it's so important, why weren't they carrying the 'right' sized tube in the first place?
Title: Re: "We've got a tube but it's the wrong size"
Post by: Polar Bear on 03 April, 2011, 05:20:16 pm
I have a friend who is an academic genius.   He has no idea at all about how to sort his bike and he struggles with changing batteries on his TV remote let alone a bike lamp.   

We all have differing talents...
Title: Re: "We've got a tube but it's the wrong size"
Post by: Adrian on 03 April, 2011, 05:23:22 pm
I have a friend who is an academic genius.   He has no idea at all about how to sort his bike and he struggles with changing batteries on his TV remote let alone a bike lamp.   

We all have differing talents...

Are you sure this isn't an affectation?
Title: Re: "We've got a tube but it's the wrong size"
Post by: Arch on 03 April, 2011, 05:24:19 pm
I have a friend who is an academic genius.   He has no idea at all about how to sort his bike and he struggles with changing batteries on his TV remote let alone a bike lamp.   

We all have differing talents...

Oh, sure.  I was once stood with a group of colleagues trying to buy a subway ticket in Mexico City, and we were failing to understand the stunningly simple system* until a helpful English speaker helped out.  I worked out later, our group of 5 had about 20 degrees of various forms between us...

*any trip, 2 pesos. Any distance, if it's one trip through the gates, it's 2 pesos.  We were assuming all sorts of zones and stuff.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Rhys W on 03 April, 2011, 05:39:57 pm
What's more amazing to me is that the couple of cyclists who were clearly inexperienced, refused to accept the opinion of a group of riders who presumably clearly knew what they were talking about.

Yes exactly. They admitted they were clueless, and they asked us advice about doing a charity ride. But they were adamant the tube they had would not do.

Anyway, it's already become a clubrun meme. We suffered a puncture today on the way home and somebody asked why they were taking so long... "they have a tube but it's the wrong size!"  ;D
Title: Re: "We've got a tube but it's the wrong size"
Post by: Kim on 03 April, 2011, 05:43:02 pm
It's amazing that people can't deal with such an easy repair, but then again many people can't deal with a flat on a car, and that's generally easier than one on a bike (in my limited experience).

I dunno, they're fairly different skills.

Getting a car wheel off means undoing the wheel nuts.  That means knowing about and having the key for the locking nuts if it's a modern posh car, and having enough strength/mass/leverage to undo a bolt that was probably done up a couple of years ago by a guy at Kwik-fit with an impact wrench.  An awful lot of people are going to fail at that hurdle.  Lifting car wheels isn't exactly trivial strength-wise either.  Oily dykes and cyclists aside, I don't think I know many women who'd even bother trying.

Bike tyres can be bastards to get back on the rim, but there are at least tools and knacks that can help with that.

Of course, modern cars tend to come with a can of slime and a compressor, or if you're really lucky, a tesco value space-saver spare wheel, which seems to be more of an effort to cover legal requirements rather than something that's expected to be genuinely useful, and the expected procedure is to call the AA from your mobile phone.  I think there's a general assumption amongst non-cyclists that punctures are as rare as they are on car tyres, and that similar levels of preparedness are therefore appropriate.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Jasmine on 03 April, 2011, 09:02:25 pm
Is there no one else who will admit that they have sufficient hatred of changing tubes & tyres that they will feign patheticness?

Am I capable of changing a tube? Yes
Do I hate it? Yes
Do I find that standing by the side of the road elicits male cyclists to stop and offer to help? Yes
Have I ever needed to stand for more that 10 minutes? No
Would it have taken longer than that to do myself? Yes
Does that make me shameless?  Probably
Do I care? No

Most people on yacf seem to like fiddling around with their bikes.  I like to ride mine.  I get no joy whatsoever from cleaning/adjusting/faffing around with it. 
Title: Re: "We've got a tube but it's the wrong size"
Post by: Kim on 03 April, 2011, 09:10:08 pm
Most people on yacf seem to like fiddling around with their bikes.  I like to ride mine.  I get no joy whatsoever from cleaning/adjusting/faffing around with it. 

Heresy!   :P


(I have no particular love of faffing about with tyres, unlike more satisfying forms of fettling, but I'd be too embarrassed to not sort it out myself.)
Title: Re: "We've got a tube but it's the wrong size"
Post by: clarion on 03 April, 2011, 09:10:40 pm
The above method does not work if you are not an attractive young woman.

Fact.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Butterfly on 03 April, 2011, 09:13:42 pm
The above method does not work if you are not an attractive young woman.

Fact.

I don't know - myself and an elderly lady stopped to help an incompetant and unprepared chap on a canal tow path once ;D. I hope he was suitably embarassed by a 70 something lady mending his puncture!
Title: Re: "We've got a tube but it's the wrong size"
Post by: Kim on 03 April, 2011, 09:14:39 pm
The above method does not work if you are not an attractive young woman.

I dunno, I've stopped and provided mechanical assistance (usually chain-related, for some reason) to random middle-aged blokes before now.
Title: Re: "We've got a tube but it's the wrong size"
Post by: clarion on 03 April, 2011, 09:15:34 pm
OK.  The exception is for very kind women passing :)  Or Regulator, if one is a fit young adonis (not Lord Adonis)

But I could be waiting a long time...
Title: Re: "We've got a tube but it's the wrong size"
Post by: Steve Kish on 03 April, 2011, 10:17:52 pm
I always offer to change tubes because I actually like doing it. :)
Title: Re: "We've got a tube but it's the wrong size"
Post by: damerell on 04 April, 2011, 12:48:27 am
The above method does not work if you are not an attractive young woman.

I've been offered assistance once or twice, and I ain't a young woman, leastwise.

A few years ago I was on the London->Cambridge (yes, charity ride, gah!) with a friend who punctured. He had no spare tube or pump (or any puncture supplies); I had them, but he had a big hole in a Slimed tube so there was no getting a patch on it... and to be frank, besides the 26" vs 700C issue, I was not going to give up my spare tube when I might need it later for someone so ill-prepared.
Title: Re: "We've got a tube but it's the wrong size"
Post by: DrMekon on 04 April, 2011, 01:31:24 am
I've been guilty of assuming that I'd get away with Marathons + slimed tubes. The other evening, cornering very hard on the cargotrike, the outside front tube blew spectacularly - green gloop oozing out from under the bead. I don't know if the cornering was somehow responsible, but the tube had ripped across the seam. Couldn't see that anything had penetrated the tyre. Anyway, the effort of riding a cargotrike with a 5 year old in for a couple of km on two wheels was enough to make me form a very strong prospective memory to take spare tubes and a pump from now on.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Cudzoziemiec on 04 April, 2011, 02:55:47 am
I reckon these guys were suffering from an overdose of specificism. It tends to be related to overconsumption of TV ads and general marketing guff, and can also be known as unitaskism. In general, the belief that everything has to be perfect and only the correct, manufacturer recommended, TM and C, item will do.

The above method does not work if you are not an attractive young woman.

Fact.
I'm not young, not a woman, and definitely highly unattractive in every way imaginable  :demon: but whenever I got a puncture in India I was alway quickly surrounded by "helpers". Sometimes genuinely helpful, at others their "assistance" consisted of crowding round me as tightly as possible asking how much the bike cost and telling me there was a garage at such and such a place. But I guess that's India specific, rather than me!

The "best" puncture I ever had was also in India and on an MTB. Zooming down a hill I suddenly saw an object about a foot in front of my tyre. I realised it was a screw or bolt and remarkably it was standing on its head, vertically. Immediately, kerthunk, I rode over it. There was a ping and another kerthunk as it shot out from under my front wheel and hit my back tyre. How dead straight a line does everything have to be in - the initial object on the ground, both my wheels and my direction of travel, all lined up perfectly - for that to happen? And then there was the inevitable hiss. From "ooh, what's that on the road?" to "Shit, puncture!" in less than two seconds.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Cudzoziemiec on 04 April, 2011, 03:02:03 am
I'd rather knit my own tube from beetles than call a taxi.
;D  ;D  ;D

Such a wonderful line I think I'll have to sig it, if you don't mind!  :thumbsup:
Title: Re: "We've got a tube but it's the wrong size"
Post by: Jasmine on 04 April, 2011, 09:26:41 am
Most people on yacf seem to like fiddling around with their bikes.  I like to ride mine.  I get no joy whatsoever from cleaning/adjusting/faffing around with it.  

Heresy!   :P


(I have no particular love of faffing about with tyres, unlike more satisfying forms of fettling, but I'd be too embarrassed to not sort it out myself.)

I know.  I'll get thrown out of here soon.

I know how to do all types of bicycle maintenance.  First step is find 'a man'*
I even have a man to clean & lube all my bikes.  If I've been to an event and left a bike in his car it will come back to me clean & serviced the next day.  How nice is that?!  :D
I probably should be embarassed, but I'm just not**  :P



*where 'a man' is a non-gender specific term for someone who does it for a living or enjoys doing it.

**the above approach may be less successful for those people whose other half is not a bike mechanic
Title: Re: "We've got a tube but it's the wrong size"
Post by: Arch on 04 April, 2011, 11:39:23 am
If you're happy leaving it to someone else, and they are happy to do it , fine.  My caveat would be though, to make sure you CAN do stuff, even if you never think you'll have to.  Otherwise, one day, you will be miles from anywhere, alone, with no phone, no one around and stuck. All the fluttering eyelashes in the world won't help then.

If I'm out with certain friends, I know I won't get a look in at a mechanical, because they'll be falling over themselves to fettle it. Not, I'm sure, because I'm a girl, but beause they're all keen macklers.  As a result, they'll probably be much faster and more efficient than I would be.  But at least I know that when I'm out alone, I can tackle most stuff I'd need to.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Jasmine on 04 April, 2011, 11:49:46 am
Oh, I can change tubes, and I can do it properly without using tyre levers to get the tyre back on.

tbh, if I'm out with other people then they will usually have offered before I've even identified the source of the flat.  I have almost no feeling in my hands, so whilst it's funny to watch me try to drink out of paper cups (think alternating between dropping and crushing), it's just painful to watch me doing anything that requires fingers.
Title: Re: "We've got a tube but it's the wrong size"
Post by: hellymedic on 04 April, 2011, 02:40:25 pm
Dervla Murphy can't fix a puncture. This did not appear to impede her adventures awheel.
Personally, I do not recommend this approach.
Title: Re: "We've got a tube but it's the wrong size"
Post by: CrinklyLion on 04 April, 2011, 03:02:13 pm
I can fix a flat.  And indeed have - on all our bikes when necessary, and a couple of bikes belonging to EldestCubs mates.  But I take blinking ages about it because I am a complete klutz.  If I was riding with someone more adept than me I'd have no qualms at all about letting them effect a repair because that would get us on the road and moving again significantly quicker.  I do carry the necessary - although I ought to get a couple of replacement spare tubes because the ones I have were a bit fat for the old 32s, so with the new 28s my chances of getting a tyre back on without cocking it up (see above reference to klutz-ishness) are not great.

And I am to this day eternally grateful to Mseries, Deano and toekneep (who had an appropriate spare cable with him despite it not being needed on his or GillP's bike and who went up and down Little Fryupdale a frankly silly number of times because of my mechanical) for fettling my Stupid_Disk_Brakes into submission on the KTTR ride, because my only other option was a very long walk to a very long wait at an infrequently served train station.  This is the reason that a) I now carry a spare brake cable and b) any n+1 in my life is unlikely to have disk brakes - I can almost understand rim brakes, and would have a chance of figuring out how to fettle them.  But disks are strange and perplexing voodoo.
Title: Re: "We've got a tube but it's the wrong size"
Post by: Kim on 04 April, 2011, 03:22:51 pm
I do carry the necessary - although I ought to get a couple of replacement spare tubes because the ones I have were a bit fat for the old 32s, so with the new 28s my chances of getting a tyre back on without cocking it up (see above reference to klutz-ishness) are not great.

So you literally do have a tube, but it's the wrong size  \o/


Quote
This is the reason that a) I now carry a spare brake cable and b) any n+1 in my life is unlikely to have disk brakes - I can almost understand rim brakes, and would have a chance of figuring out how to fettle them.  But disks are strange and perplexing voodoo.

Cables are well worth carrying, I reckon.  But not those double-ended ones (road and mountain brake lever knobbles on the same cable, if you've not met them), unless you're also carrying something that's up to cutting the wrong end off and awake enough to make sure you don't cut the right end off instead.  Don't ask how I know this.

I'm suspicious that your disc brakes are a particularly awkward example of the species, having had a brief look and decided that on account of it being 1am and lacking a workstand, it wouldn't be a good idea to fiddle.  As you say, there may be a low-end Shimano factor, especially regarding the thickness (or lack thereof) of the rotors.  My low-end Tektros (and the truly awful disc-brake-shaped-object on the tandem) do at least have the decency to only have two clearly defined adjustments to cock up, where yours are bristling with tweakables.

I reckon a decent set of rim brakes are absolutely fine for most bikes though - with decent pads they're fine in the wet.  Discs are great for mud or having to dissipate abnormal amounts of heat (as on a tandem or recumbent), but aren't really an advantage for normal use.
Title: Re: "We've got a tube but it's the wrong size"
Post by: henshaw11 on 04 April, 2011, 07:40:55 pm
>I'm not young, not a woman, and definitely highly unattractive in every way imaginable  demon but whenever I got a puncture in India I was alway quickly surrounded by "helpers". Sometimes genuinely helpful, at others their "assistance" consisted of crowding round me as tightly as possible asking how much the bike cost and telling me there was a garage at such and such a place. But I guess that's India specific, rather than me!

A mate did a motorcycle tour round africa some years ago (on a Royal Enfield too,subject to some rather misplaced logic, but there y'go..). The inevitable happened. Tyre levers bend - he's not tried using them before (despite having a spare set of tyres strapped to the bike that he was expecting to swap over at some point).
Enter local wanting to help, and assorted rock-on-tyre violence 'til the tyre's off. New inner tube in, assembly's the reverse of disassembly via aforementiond rock...and the new inner (probably c/o the assorted violence) is holed too !
Starts walking with bike, gets round corner and finds a bike shop that sorts it out for 1 euro  :facepalm:
Title: Re: "We've got a tube but it's the wrong size"
Post by: Cudzoziemiec on 04 April, 2011, 10:09:31 pm
10 rupees I paid (about 13p) for a puncture on my Hero Hawk to be fixed.  ;D
Title: Re: "We've got a tube but it's the wrong size"
Post by: GrahamG on 07 April, 2011, 09:59:56 am
I helped a guy out a few months ago on the bike path here in Brizzle - he'd just moved back from living in China for a few years so his excuse for not carrying a tube or spares was that he was just too used to being able to just pull over and get one of the dozens of roadside bike mechanics to fix it for like 10p!

Nice chap - returned my loaned tube (I squeezed my 700x25 into his 38mm hybrid tyre at low pressure ;)), and gave me a bottle of wine!
Title: Re: "We've got a tube but it's the wrong size"
Post by: Bledlow on 07 April, 2011, 11:35:34 am
On an MTB with knobblies, I'd have thought you could ride a fair bit on a flat tyre, if you put your mind to it.
MTB tyres are often less of a tight fit than road tyres. The tyre might come off on its own if ridden when flat. I've seen it happen.
Title: Re: "We've got a tube but it's the wrong size"
Post by: richie on 07 April, 2011, 12:55:17 pm
On an MTB with knobblies, I'd have thought you could ride a fair bit on a flat tyre, if you put your mind to it.
MTB tyres are often less of a tight fit than road tyres. The tyre might come off on its own if ridden when flat. I've seen it happen.

My MTB runs Mavic Rims and Fire XC 2.1 tyres.  The tyre will fall off the rim on its own accord if totally deflated.   Seems fine when pumped up though.

On another note, during the cold spell before Xmas i was pedalling  some Exmoor lanes at night in -3 temperatures when i got a rear wheel puncture.
Just as I was finishing the repair, a helpful car driver stopped with the advice 'be careful, it might be icy'.

Not sure how i managed not to be offensive as i gazed around at the rime-encrusted landscape and just said 'Thanks for letting me know'.

 
Title: Re: "We've got a tube but it's the wrong size"
Post by: Salvatore on 12 April, 2011, 01:37:01 pm
On Sunday, far from home and 15 km from the nearest Halfords, I needed an inner tube for the 16" x 1.75" tyre on my Bob Yak, the original being irreparably split. I did have spare tubes, but as these were for 700x23 tyres, some might say that at twice the circumference and half the cross-section, they were "the wrong size".

But it occurred to me that looped round twice, it is roughly the right circumference and roughly the right cross section, so I tried it. And it worked, and got me home.

Title: Re: "We've got a tube but it's the wrong size"
Post by: TimO on 12 April, 2011, 01:40:49 pm
Funnily enough, my Bob Yak has a flat at the moment, and I know I've got a spare somewhere, but I'm not sure exactly where!  It'll probably be easier to just pop the tube out and repair it.  I don't think I'll try you're twice around the wheel approach. :)
Title: Re: "We've got a tube but it's the wrong size"
Post by: The Seldom Killer on 14 April, 2011, 02:20:37 pm

On an MTB with knobblies, I'd have thought you could ride a fair bit on a flat tyre, if you put your mind to it.


Done about three miles at night at the end of a day when it was cold, wet and I was in no mood to stop to do a repair. It would have been about seven miles but by then my girlfriend had got to a pub and bribed a man with a van a pint to come and scrape me off the road.

I then set in a pub with my new friends while my girlfriend went and got our van, which was nice.