Thorn Cycles Forum
Technical => Transmission => Topic started by: ourclarioncall on April 04, 2021, 07:22:57 pm
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Just wondering what a puncture repair would be like in a real life scenario for me
My current method of puncture repair would be just take the old tube off and put on a new one I have spare in my bag.
To do that I guess requires taking off the wheel . Let’s say we are talking about a back wheel puncture
And let’s say it’s dark , it’s in the middle of countryside , it’s windy , it’s cold and it’s raining . This would be a genuine scenario for me as I commute to or from work on a 10 mile journey .
The side of the road where I would have to fix the puncture would probably be very rough and not flat.
I would be prepared , like having good quality clothing and gloves etc
But how easy or difficult is it going to be ? Am I going to have to open up the chain to take it off? Or is there enough slack to take it off the sprocket ? Will I have to adjust the eccentric ? What about a belt ?
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With a chain and without a chainguilder (Because that's all I know) it's easier than it is with a derailleur bike. Undo the thumbscrew on the ex box, loosen skewer, drop wheel out, fix, replace, do up skewer, reattach ex box (It just fits on a couple of pins) screw in thumb screw, job done. There's no derailleur to knit the chain around, so it's also cleaner.
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Cool, that does sound simple enough actually
I guess if there’s a chainglider involved you could just shove it in a bag and put it back on later if weather is wild
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Once you've got the wheel out of the drop-outs then it's easy to move it slightly towards the bottom bracket and get the chain (or belt) off the sprocket. If there's the risk of cycling at night then it would be prudent to pack a small torch, perhaps one which you can hold between your teeth or clip onto your clothes. A head torch is another option that's more practical to use but bulkier to carry.
The chainglider clips together. It's quite easy to pull apart and push together again. You only need to unclip the rear part, which covers the sprocket, in order to remove the chain and free the wheel. The front part of the chainglider isn't opened. All maintenance is best practised at home before going on a long ride. You might discover that you need another tool or something has been fixed so tight that it can''t be undone by whatever tools are carried on the bike.
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I actually find removing the rear wheel easier to do with a Chainglider than with an uncovered chain. But I think I have only done this at home, and nearly always to change tyres rather than for punctures (studded tyres on or off at start and end of icy season, replacing worn tyres)
The extra step of removing the rear of the Chainglider is compensated (for me) by the front parts keeping the chain on the chainring and stopping most of the chain flopping onto the ground.
If the weather was OK, for a rear wheel puncture away from home I would probably try the Dutch method and patch the tube without removing the wheel.
Not absolutely certain, but so far I don't think I have had to mend a rear wheel puncture by the roadside on a Chainglider-equipped bike. Though not supposed to be puncture proof the Schwalbe Marathon Supreme tyres I use on most Chainglider bikes have had very few punctures.
For the two visitor bikes I have fitted Schwalbe Marathon Plus tyres on the rear, these are very puncture resistant, the idea being to avoid hassle with a visitor bodging rear wheel removal and messing up the gear cable adjustment, which is quite critical on these two bikes that have Shimano Nexus Premium hub gears.
Unlike the 700C x 28 version, which I found horrible to ride on my old visitor bikes, in the 50 mm width on the current two visitor bikes the Marathon Plus on the rear wheel doesn't feel too uncomfortable to ride, and doesn't seem to affect efficiency very much. So it might be a good option to reduce hassle on tour if mending a puncture is an issue for someone. Personally, on long rides I prefer the slight increase in efficiency and comfort of the Marathon Supreme at the cost of having to mend an occasional puncture.
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In theory there's also the tubeless option which should reduce the frequency of needing to remove the wheel. However, that convenience is more than offset by the big challenge of getting a tubeless tyre seated on the rim. A compromise is to put some sealant in the inner tubes. This should be sufficient to handle smaller punctures.
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JohnR
Definitely a good idea to run through the process nearer to home at least once.
And prepare for worst case scenario
I got caught in heavy rain and wind one night on way home from work , my goretex jacket and trousers are really good , but still not up to the task in weather like that
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Martinf
How do you repair puncture with tyre on ? I remember as a kid putting the tube under water looking for leaking air bubbles (well that was probably my dad not me. The bike had probably sat there for 6 month 😆)
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Just wondering what a puncture repair would be like in a real....
But how easy or difficult is it going to be ? Am I going to have to open up the chain to take it off? Or is there enough slack to take it off the sprocket ? Will I have to adjust the eccentric ? What about a belt ?
I make it easy by carrying not only a spare inner tube but also a spare tyre (I use folding tyres which weigh about 440g and fold up quite neatly in the pannier.. So, I remove the tyre and inner tube and replace both then deal with the puncture in the warm, dry and calm at home (or that could be the B&B or campsite if you’re touring). I feel it’s worth it to carry these spares even on day rides.
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Without removing the wheel, one bead of the tyre has to be levered off the rim.
This video shows the principle. It shows a front wheel, as it is easier to do the video without the chain and rear triangle getting in the way.
Front wheels are easy to remove, so I only bother to do this with a rear wheel, where removing the chain and hub gear cable, and sometimes the cable for a hub brake, can make it worth using this method. It won't work in very wet or cold weather.
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I make it easy by carrying not only a spare inner tube but also a spare tyre (I use folding tyres which weigh about 440g and fold up quite neatly in the pannier.. So, I remove the tyre and inner tube and replace both then deal with the puncture in the warm, dry and calm at home (or that could be the B&B or campsite if you’re touring). I feel it’s worth it to carry these spares even on day rides.
As destroying a tyre is a rare event in my experience I don't generally bother carrying a spare.
In about 48 years of cycling and about 266,000 kms I have only had 3 tyre failures that were bad enough to need immediate replacing or bodging a repair to limp to somewhere I could buy a new one. I have had the same number of frame/fork failures, and nobody would think of carrying spares for these.
The first, in the old narrow 26" size, could have been bodged with the tyre "boot" in my toolkit if necessary, but I was less than a mile from a bike shop when it failed, so I didn't bother and just bought a new one.
The second was a very cheap and inferior 27" tyre, and I got a replacement for that in less than an hour from another cyclist. Lesson learnt - get decent tyres.
And the third was a lightweight 16" tyre on my Brompton. But as I knew these were fragile and in a size that was hard to find I did have a spare with me that time. And with a folding bike I also had the option of finishing the trip by public transport.
I reckon that the reliability of good touring tyres has improved in recent decades. The first two failures were in the 1970's, and I haven't had a catastrophic tyre failure on a large-wheel bike since then.
I would still definitely take a spare if going somewhere really remote, but in most of Europe I reckon it is easy enough to find a 26" tyre.
And before I go on a tour if I think a tyre is a bit too worn I replace it with a new one, and generally put the part worn tyre on a utility bike to finish it off on local rides.
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I make it easy by carrying not only a spare inner tube but also a spare tyre (I use folding tyres which weigh about 440g and fold up quite neatly in the pannier.. So, I remove the tyre and inner tube and replace both then deal with the puncture in the warm, dry and calm at home (or that could be the B&B or campsite if you’re touring). I feel it’s worth it to carry these spares even on day rides.
As destroying a tyre is a rare event in my experience I don't generally bother carrying a spare.
In about 48 years of cycling and about 266,000 kms I have only had 3 tyre failures that were bad enough to need immediate replacing or bodging a repair to limp to somewhere I could buy a new one. I have had the same number of frame/fork failures, and nobody would think of carrying spares for these.
The first, in the old narrow 26" size, could have been bodged with the tyre "boot" in my toolkit if necessary, but I was less than a mile from a bike shop when it failed, so I didn't bother and just bought a new one.
The second was a very cheap and inferior 27" tyre, and I got a replacement for that in less than an hour from another cyclist. Lesson learnt - get decent tyres.
And the third was a lightweight 16" tyre on my Brompton. But as I knew these were fragile and in a size that was hard to find I did have a spare with me that time. And with a folding bike I also had the option of finishing the trip by public transport.
I reckon that the reliability of good touring tyres has improved in recent decades. The first two failures were in the 1970's, and I haven't had a catastrophic tyre failure on a large-wheel bike since then.
I would still definitely take a spare if going somewhere really remote, but in most of Europe I reckon it is easy enough to find a 26" tyre.
And before I go on a tour if I think a tyre is a bit too worn I replace it with a new one, and generally put the part worn tyre on a utility bike to finish it off on local rides.
I don’t carry the spare tyre only as a precaution against destroyed tyres. If I get a flat unless the cause is very obvious and can be removed completely ,I don’t bother look too hard for the cause or locate the puncture in the tube, I just remove the wheel, take off the tyre and inner tube and replace with spares.
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UKTony
Is your method a bit quicker or easier ?
I’m trying to understand why not just put on a new tube? Why the tyre and tube?
Do you partially inflate the tube so there is some air already in it? I haven’t changed many punctures but I’m sure when I watched a video some time ago it was easier to get tube and tyre on with it partially inflated
Cheers
I also never thought about carrying a spare tyre. Could certainly come to the rescue of your on tour
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MartinF
I’m not seeing a link if you attached one
North east Scotland where I’m at can be very “dreich”, cold windy damp Misty , think I would rather just rip the thing off. Okay I’m summer I suppose which up here is a few weeks per year 😆
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UKTony
Is your method a bit quicker or easier ?
I’m trying to understand why not just put on a new tube? Why the tyre and tube?
Do you partially inflate the tube so there is some air already in it? I haven’t changed many punctures but I’m sure when I watched a video some time ago it was easier to get tube and tyre on with it partially inflated
Cheers
I also never thought about carrying a spare tyre. Could certainly come to the rescue of your on tour
Fitting a new inner tube saves time having to find and repair a puncture. However, there’s no point fitting a new inner tube unless the cause of the puncture, e.g. thorn, tiny sliver of grit, is found and removed completely. Otherwise there’s a possibility that the new tube will be punctured and flat in a couple of miles further down the road. In poor weather, (wet or cold) especially, I’d much rather replace the lot and deal with the punctured tube and it’s cause(s) at home.
I used to fit beaded tyres and position the inner tube without slightly inflating it. However with folding tyres I think fitting is probably made a bit easier with the inner tube slightly inflated as it helps give shape to the tyre to get it on the rim. Whichever, some care is needed to avoid pinching the inner tube twixt tyre lever and rim.
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I want to add my tuppence to a couple of points in the discussion
1) I had my 15 year old fix his first puncture alone 2 weeks ago- with only verbal assistance from me. His first gripe was why I wouldn't just give him a new tube from my spares. I insisted he learns as his school bike ride in about 18 miles roundtrip, and he should not just carry a pump, but a repair kit with him from now on- just in case. He located the 'shrapnel' that had caused the hole and removed it. His bike has bolt on wheels, so I had him fix on the bike as he might need to do if out on his own without spanners. A Tesco set with 5 patches and 5ml of rubber solution was opened for the first time and one patch used. He was super proud to tell his Grandad (who bought him the puncture repair kit a few years back) that he'd ridden almost 100km since fixing it and it is still holding firm. 15 minutes needed from start to finish with a beginner who is now empowered to fix his bike himself 'on the go' if needed.
2) Tubes are cheap- but there is a bigger environmental impact if we always replace with new. Don't think about the negligible cost of a cheap tube- but the environmental cost of throwing away a fixable tube. MOST flats can be fixed easily from my experience- and by a novice with willing to learn! There is an argument to have the odd spare tube. I carry a repaired spare with me on longer trips- just in case.
3) A torch to fix a flat? Murphy's Law applies especially strictly to bike riders. Murphy was clearly a petrol head with no tolerance of bike riders! His law to cyclist is that is always dark when something breaks. And rainy. And Cold. And when nearest bike shops are otherwise shut. Last point is largely irrelevant as you will always be miles from the nearest bike shop anyhow!
Most of us carry mobile phones. If you don't have a suitable torch with you- remember your phone 'flashlight' function. If you have the right phone cover, this can often be angled as a stand for watching youtube. The stand can also be used to angle the light at the bike part needing attention. So youtube your bike fixes if in a pickle, and then use your phone to light the way if required.
4) Many flats are avoidable even with good quality puncture resistant tyres. Check your tyres regularly and remove sharp objects you spot BEFORE you get a puncture. Rubber perishes, so if you see signs of cracking/splitting even with otherwise good tread- better to replace tyre as a repaired tube won't help you if tyre is shot. Even on non porous tyre, if you notice a bulge in the tyre sidewall- be cautious and replace ASAP. And if you ride rim brakes, a bulge in the braking surface of wheel can lead to rim and tyre failure. Blow outs are normally too big to repair. And they happen exclusively following the Murphy's rules mentioned in point 3.
Sometimes you do need to remove the wheel though to fix a flat. I cannot comment on belt drive. But Hebie Chainglider opens up and snaps back together without tools. It is not rocket science, but not immediately obvious unless you have removed and refitted it a couple of times. First couple of times I needed to open mine I looked on youtube for peace of mind. But the plastic/nylon (or whatever it is made from) is pretty robust against pushing and pulling the wrong ways, and even if you are doing it wrong, you are unlikely to break it unless you really put your mind to it. removing sprocket cover and rear retaining part literally takes less time than reading half of this message. And refitting it takes the time to get to this sentence in the text. So you are not really adding much time to the job. In fact, with a chainglider, you will save time by getting less messy because your chain is far cleaner than an open chain- so washing your hands after needs less time/effort as you should be less grubby. ;D
But don't let worries of maintenance put you off. Cars are more tricky to fix, and far harder to push home when they break down! :o
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MartinF
I’m not seeing a link if you attached one
Sorry about that, forgot to check before posting :
https://www.youtube.com/watch?v=uxVzNNdqJxc
North east Scotland where I’m at can be very “dreich”, cold windy damp Misty , think I would rather just rip the thing off. Okay I’m summer I suppose which up here is a few weeks per year 😆
Repair without removing the wheel doesn't work well in bad weather, rubber solution doesn't stick if the tube is wet. Though I have done repairs this way a couple of times when adequate shelter has been at hand (bus shelter, barn).
I decide between "wheel removal with tube swap" or "in-situ" repair depending on the circumstances.
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Firstly - Are we sure we're not getting this out of proportion? Punctures are an inevitable part of cycling life, but unless it's absolutely critical to be somewhere at a very specific time, getting one isn't the great inconvenience some seem to think it is. Modern tyres do a pretty good job of resisting them, you can go all the way up to plus type to almost eliminate the possibility, but even the lighter touring tyres I prefer like Supreme and Almotion don't puncture as often as the tyres I used a decade or so ago. I've worn out several Supreme tyres that have never punctured and I think I had two in last years 7,000 miles, one of which went down overnight at home.
My favourite puncture repair tip if on a long ride is to eat something before you tackle it. Not only will that mean your blood sugar is high and you'll think better, it could also be the last time your hands are clean for a while. I once came across an experienced looking rider in the middle of nowhere on a winter Audax, struggling to replace his wheel, couldn't get it past the brakes, mainly because he hadn't spotted the bulge of inner tube sticking out. He wasn't incompetent, just cold and hungry.
On the bike that's never more than ten miles from home, I don't even carry a tube or the spanner needed to remove the rear wheel. Just levers a pump and some Park instant patches. In the unlikely event that isn't enough, it'll be a taxi home, but in about five years of riding almost every day, that hasn't happened yet. On the folder that only comes on train journeys, I don't even carry that, if I get a puncture I'll have missed the train anyway.
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...it could also be the last time your hands are clean for a while.
This is why I always carry a pair of nitrile gloves in my kit. Easy on/off and keeps the hands clean for later things like unstuffing expensive down sleeping bags when I make camp. I don't think there's a device made that better removes grease from hands than a down bag -- the more expensive and newer, the more efficient. ::)
Best,
Dan.
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...it could also be the last time your hands are clean for a while.
This is why I always carry a pair of nitrile gloves in my kit. Easy on/off and keeps the hands clean for later things like unstuffing expensive down sleeping bags when I make camp. I don't think there's a device made that better removes grease from hands than a down bag -- the more expensive and newer, the more efficient. ::)
Best,
Dan.
Yes, the retired Medical Doctor in our cycling group has taught us a lot about the ins and outs of using nitrite gloves. If he shouts “puncture !” you don’t see the rest of us for dust😳
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Firstly - Are we sure we're not getting this out of proportion? Punctures are an inevitable part of cycling life, but unless it's absolutely critical to be somewhere at a very specific time, getting one isn't the great inconvenience some seem to think it is. Modern tyres do a pretty good job of resisting them, you can go all the way up to plus type to almost eliminate the possibility, but even the lighter touring tyres I prefer like Supreme and Almotion don't puncture as often as the tyres I used a decade or so ago.
Totally agree for myself. The occasional puncture only bothers me if :
- it is with my Brompton and I need to catch a train or ferry. So I mainly used Marathon tyres on that when I was commuting, and have moved to lighter tyres since retiring.
- it is really cold. Once in the past 15 years ago.
If punctures are an issue, Marathon Plus tyres significantly reduce the possibility. I have had them on visitor bikes for about 15 years without ever having a rear-wheel puncture. Though the Supremes I fit on the front wheels of the visitor bikes have been just as reliable so far.
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Firstly - Are we sure we're not getting this out of proportion? Punctures are an inevitable part of cycling life, but unless it's absolutely critical to be somewhere at a very specific time, getting one isn't the great inconvenience some seem to think it is. Modern tyres do a pretty good job of resisting them, you can go all the way up to plus type to almost eliminate the possibility, but even the lighter touring tyres I prefer like Supreme and Almotion don't puncture as often as the tyres I used a decade or so ago.
Totally agree for myself. The occasional puncture only bothers me if :
- it is with my Brompton and I need to catch a train or ferry. So I mainly used Marathon tyres on that when I was commuting, and have moved to lighter tyres since retiring.
- it is really cold. Once in the past 15 years ago.
If punctures are an issue, Marathon Plus tyres significantly reduce the possibility. I have had them on visitor bikes for about 15 years without ever having a rear-wheel puncture. Though the Supremes I fit on the front wheels of the visitor bikes have been just as reliable so far.
Most of my cycling is commuting. Almost all punctures I recall seem to be on the way to work- raising my stress levels exponentially. I cannot recall ever getting a flat on longer tours except once about 5km from next town on a 90km ride on a Sunday. I had a mini pump which struggled to get to the required pressure once I'd repaired. I could manage about 700 meters and need to repump to keep going. On reaching the town I found a petrol station, pumped to around 5 bars and hisssssssssss. I had failed the initiative test and rushed. I hadn't felt the inside of the tyre, and a tiny remnant of glass at point I'd repaired had repunctured right next to the first repair. Hence the gradual loss with the mini pump. The 2nd repair held well and the ride could complete. We missed our planned train home at end of the tour, and had to wait around 90 minutes.
I was riding on Schwalbe Cityline tyres at time which rode quite 'lightly' but, despite good tread, let me down that winter puncturing more than once on road grit shards- which is how I discovered the joys of the Marathon range. For me the better compromise.
A stitch in time saves nine! Don't rush the repairs- but you don't get to choose when flats will strike. But puncture resistant tyres do reduce those risks.
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Something to try to remember to do before completely removing a tube from a tyre is to put a couple of marks on one side of both the tube and the tyre (the yellow wax crayon in most patch kits can be used). These marks can then be used as reference so, once the hole in the tube has been found then the corresponding place in the tyre can be identified for closer scrutiny to find the offending object.
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Near home, carry one spare tube on my bike. When touring, carry two tubes plus a self adhesive patch kit. I find that the self adhesive patches only last months, but months is good enough for a tour, I can glue a patch on at home.
Like Dan, I also have a pair of medical gloves with my spare tube. Pre-Covid, it was easy to ask at the dentist or doctor office for a few spare pairs for bike repairs. But now that stuff is valuable, I do not even ask now.
I also keep a piece of Tyvek cut from a postage envelope in case I need a tire boot. Never used one yet, but maybe my preparation means I never will?
Keep my tube clean in a plastic bag, I do not want a bit of grit like a sand particle to stick to it and get inside my tire. If that happens, that will be the next flat. When at home, I wash off the wheel and tire to remove all grit before removing a tire, but that is impractical on a roadside repair, but I still take great pains to keep any grit out of my tire and tube interface. Back in the days when trucks used inner tubes, I was replacing a wheel on my truck in the middle of the night because the mechanic that had changed my tire a few hundred miles before let some grit get into the tire. I mention this because I have seen mountain bikers carry a bare tube where dirt and mud can get all over it.
I do not mark my tube and tire for reference, but I always put the valve stem centered at the tire label. That way if I find where the puncture in the tube is, there are only two possible places that I need to inspect the tire.
I do not use tubeless and have no plans to do so. I average about one flat a year. But I ride half a dozen different bikes in a year, I would rather deal with one flat than have to deal with sealant in half a dozen tires for annual maintenance.
I had a flat about five years ago, the tube suddenly started leaking and the puncture was extremely close to the valve stem, so close it could not be patched. I used to use metal presta to shrader adapters to use presta tubes in shrader rims. And the metal apparantly rubbed on the tube. On all my rims I replaced those with the Mavic plastic ones. And just to make sure, I have cut small squares of rubber from an inner tube, punched a small hole in that square and stretched that over the valve stem. Now there is a piece of sacrificial rubber between my rim and tube at the valve.
https://www.sjscycles.co.uk/rims-tape/mavic-rim-valve-hole-drilling-converter-insert-schraeder-to-presta/
I once commented that Lezyne pumps that thread on and off the presta valve stem on tubes with removable stems, sometimes the valve stem stays in the chuck when you remove the valve stem. Dan had mentioned Loctite, which I now use but I am extremely careful to make sure it is only on the threaded part of the valve core and none of that is on the valve face. Plus wrenched tight.
A friend of mine lost a presta valve stem, it shot out of the valve stem under pressure. It apparently was not threaded in tight. That is another reason to carry a spare tube.