Puncture repair

yahoo_moe

Okay, despite a bad fall and a run-in with an over-enthusiastic bus, today was possibly my worst cycling disaster in my 8 months or so on a bike - getting my first puncture when I was half-way to work.

In terms of repairing it, am I right in thinking I can just pick up a puncture repair kit somewhere and be cycling again in 10 minutes this evening or is there more to it?

Cheers

kenmc

you probably will be ok with a puncture repair kit, unless you have a broken valve or 'snakebite' punctures (two parallel lines where the tube was pinched by the rim). Get a new tube to have as a spare too. In fact I'd put a new tube in and repair the other one later when you get home, so as it has a decent time to cure the glue before you pressurise it.
Make sure to check the inside of the tyre for whatever it was punctured you, and that there are no spokes protruding too far into the tube.

Did I understand correctly though : today you fell down, got hit by a bus AND you got a puncture? And you still lived to tell the tale? nice!

seamus

10 minutes....maybe.

You can get good at it, but a quick repair isn't always a good repair. You should be able to do it in at least 30 minutes - you need to make allowances for tight tyres/rims, hard-to-find holes, etc.

As kenmc says, always easier to replace with a new tube and fix the other one later. Just make sure to check the inside and outside of the tyre for debris or you may puncture the new tube too.

Puncture repair kits generally give you a "how-to", but the way that works for me is below (someone will correct me).

1. Remove the wheel if you can and take out the tube. Rub a piece of cloth or something the whole way around the inside of the tyre to remove any debris inside. Also scan the outside of the tyre to see if it's something sticking in from the outside (like a piece of glass) and remove it.

2. Locate the puncture and determine if it's reparable. The larger the hole, the less chance you have of fixing it. If you have a snake-bite puncture - two holes near eachother on the tyre, caused by hitting kerbs, usually - treat this as two separate holes, don't try one patch over both holes. Choose a patch for the hole - you should have a good 5mm of patch on every side of the hole.

3. Circle the hole(s) with the crayon you get in the repair kit. You will lose them, so the crayon is essential for finding them again

4. Get the sandpaper and rub around the hole in a fairly wide radius - wider than the patch you intend to use. Don't be afraid to use a little elbow grease. This is essential for the patch to bond properly.

5. Put on a blob of glue and spread it out around the hole, again wider than the patch you intend to use.

6. Wait for the glue to dry slightly, between 5 and 30 seconds depending on how much glue you put on.

7. Apply the patch and press it down evenly on all sides. Rub it gently outwards from the hole for a few seconds.

8. Wait about 2 minutes, then inflate the tube slightly. Not too much - just after the point where the tube begins to stretch like a balloon. Inspect for any points on the patch where it hasn't bonded properly and listen for leaks.

9. When you're happy, dump chalk or talc on the patch and spread it around to soak up any excess glue. This prevents your tube sticking to the inside of the tyre.

10. Put the tube back in, re-seat the tyre and re-inflate.

Chips Lovell

Fitting a new tube is the fastest way to go. I always just throw out punctured ones. New tubes are so cheap that it's hardly worth hassle patching old ones.

yahoo_moe

Mmm, cheers for the explanations - think i'll defo put in a new tube anyway and I might just give the repair a bash for practice depending on how it's looking...

and just to clarify - no they didn't all happen today (as spectacular as that would've been )

Danbo!

also make sure you have everything you need apart from the tube.. pump is obvious but tyre levers are great for tight tyres. I once took the wheel off, old tube out, new tube ready to go, and realised the pump was on the other bike. now thats annoying when your in a hurry to work..

EDIT: oh and 8 months and this is your first puncture? do you live next door to work or something? thats impressive

rubadub

el tonto wrote: »

Fitting a new tube is the fastest way to go. I always just throw out punctured ones. New tubes are so cheap that it's hardly worth hassle patching old ones.

Not always faster. Say you get it just outside your house on the way home. You can take the tube out without taking the wheel off at all. Pull the tube out the side and inflate it, run your ear around it and listen for the leak - there is rarely a need for the basin of water technique. Now you find the leak gauge where it is on the tyre. It is best to align your tyre with the logo near the valve. Now check around that area for any glass etc still in the tube. Also have a look at the rest of the tyre, and run your finger on the inside.

Put the patch on and you can have it fixed without removing the wheel at all, sometimes you only have to lift the tyre off to one side too.

Some also replace since they do not trust a patch, it can have a tiny leak.

You can get tyre liners too.

the boss of me

Seamus got it mostly right but makes a common mistake when sticking the patch

. Wait for the glue to dry slightly, between 5 and 30 seconds depending on how much glue you put on

You should wait till the adhesive is totally dry, which will take 2-5 mins , depending on air temp. When the adhesive is completely dry stick the patch on .

Rub it gently outwards from the hole

rub it vigorously using the edge of a coin to "iron" it on and expel any trapped air.

Wait about 2 minutes, then inflate the tube slightly

If you have applied the patch when the adhesive is completely dry, it can be pumped up fully immediately.

Practice make perfect and you'll be an expert after the first 15 or 20

rubadub

I never knew you should let it dry completely.

Some good tips here

http://www.sheldonbrown.com/flats.html

Hungrycol

I've never raced before so what happens when you pun**ure during a race. I'm not talking about waiting for your team car or the Mavic man for a spare wheel as with the pro teams! Is it a case of get yourself a CO2 pump and change the tube as fast as you can or just give up you've already lost too much time and no one will be at the finish line when you cross it anyway?!

rubadub

Hungrycol wrote: »

I've never raced before so what happens when you pun**ure during a race. I'm not talking about waiting for your team car or the Mavic man for a spare wheel as with the pro teams! Is it a case of get yourself a CO2 pump and change the tube as fast as you can or just give up you've already lost too much time and no one will be at the finish line when you cross it anyway?!

I wondered about this. My mate was saying competitive cyclists do not like using tyre liners due to the added weight of them, centrifugal forces etc. But how many punctures would the average amatuer get per 1000miles racing. And how much loss of efficiency/time would using liners really cost.

There has to be a break even point where the liners are or are not worth it.

RiddleCon

I race and do about 6000 miles a year , I get about 2 punctures a year and have never uses liners. I ride michelin prorace 23mm tyres ans Krylion carbonns in the winter.
Rode hutchinson carbons a few years ago ang punctured 6 times in one season !. Avoiding glass, potholes and general crap as well as goos tyres will prevent more than any liners . Also read Gleg LeMond inprocycling he reckons most riders pumps the tyres to a too high pressure so stick to the manafactures guidelines.
personally don;'t repair tubes any more simply carry spares and throw out piunctured ones.
(spent far too long repairing and stiching old tubs when I was young and broke)

kona

RiddleCon wrote: »

I race and do about 6000 miles a year , I get about 2 punctures a year and have never uses liners. I ride michelin prorace 23mm tyres ans Krylion carbonns in the winter.
Rode hutchinson carbons a few years ago ang punctured 6 times in one season !. Avoiding glass, potholes and general crap as well as goos tyres will prevent more than any liners . Also read Gleg LeMond inprocycling he reckons most riders pumps the tyres to a too high pressure so stick to the manafactures guidelines.
personally don;'t repair tubes any more simply carry spares and throw out piunctured ones.
(spent far too long repairing and stiching old tubs when I was young and broke)

totally agree, better tyres and tubes are much better than crappy tyres/tubes.
stock tyres and tubes are ALWAYS ****!

kona

RiddleCon wrote: »

I race and do about 6000 miles a year , I get about 2 punctures a year and have never uses liners. I ride michelin prorace 23mm tyres ans Krylion carbonns in the winter.
Rode hutchinson carbons a few years ago ang punctured 6 times in one season !. Avoiding glass, potholes and general crap as well as goos tyres will prevent more than any liners . Also read Gleg LeMond inprocycling he reckons most riders pumps the tyres to a too high pressure so stick to the manafactures guidelines.
personally don;'t repair tubes any more simply carry spares and throw out piunctured ones.
(spent far too long repairing and stiching old tubs when I was young and broke)

totally agree, better tyres and tubes are much better than crappy tyres/tubes.
stock tyres and tubes are ALWAYS ****!

rubadub

RiddleCon wrote: »

I race and do about 6000 miles a year , I get about 2 punctures a year and have never uses liners. I ride michelin prorace 23mm tyres ans Krylion carbonns in the winter.

Say an average of 20mph, that is 300hours in the saddle.

It would take me probably 15mins to fix a puncture, just replacing the tube. That includes everything, pumping, finding a spot on the road to set the bike down, unpacking and getting tubes out of my bag etc. Some might say it should be faster but IME this is the real time for me. i.e. not a "ready steady go" setup with a bike all setup. I am talking about the delay in my commuting time.

So that would be a 30min slowdown over 300hours for me. Thats all I wonder, would the additional weight and effect of the tyre liners decrease my efficiency to a level where using liners outweighs the delay of the puncture. If you somehow had no chance of puncture you would have no need for a pump or spare tube too, so less weight. If you had "invincible" liners they could weigh less than the spares you would usually carry.

beans

After 3 punctures yesterday, it's become apparent that I need a new tyre, but aside from that what do people find most effective for re-inflating a flat on the road?

I used my hand-pump yesterday but it only got enough pressure in the tyre to get me 10 minutes down the road before I got a pinch-flat. Thinking perhaps those CO2 cylinders, but are there any better solutions?

seamus

the boss of me wrote: »

Seamus got it mostly right but makes a common mistake when sticking the patch
You should wait till the adhesive is totally dry, which will take 2-5 mins , depending on air temp. When the adhesive is completely dry stick the patch on .

You're right.
Fixed a flat yesterday (broken glass...grrr) and letting it fully dry gave great adhesion.

kona

beans wrote: »

After 3 punctures yesterday, it's become apparent that I need a new tyre, but aside from that what do people find most effective for re-inflating a flat on the road?

I used my hand-pump yesterday but it only got enough pressure in the tyre to get me 10 minutes down the road before I got a pinch-flat. Thinking perhaps those CO2 cylinders, but are there any better solutions?

petrol station, those compact hand pumps are shockingly crap:eek::eek:

i used co2 before, was great, just DONT get it on your hands its so ****ing cold it burns:eek:

seamus

kona wrote: »

petrol station, those compact hand pumps are shockingly crap:eek::eek:

Yep, I usually manage to get maybe 35psi out of the hand pump before making for the nearest petrol station. If was doing trips up the mountains or outside of urban areas, I'd probably invest in a good quality one that could get me back to full pressure on the road.

kona

seamus wrote: »

Yep, I usually manage to get maybe 35psi out of the hand pump before making for the nearest petrol station. If was doing trips up the mountains or outside of urban areas, I'd probably invest in a good quality one that could get me back to full pressure on the road.

you can get fold up track pumps, best option tbh, wont fit on the frame(why this is a issue for people i never know)
although co2 is great....if you can afford it @ €3 a whack its pricey, especially if your having a run of punctures.
afaik co2 will be lighter too as its less dense than air(i may be wrong here!!)

seamus

kona wrote: »

afaik co2 will be lighter too as its less dense than air(i may be wrong here!!)

It's technically heavier than air, but any difference would be negligible. On a weighing scales, it probably wouldn't even register.

rubadub

seamus wrote: »

It's technically heavier than air, but any difference would be negligible. On a weighing scales, it probably wouldn't even register.

Also the cylinders will weigh a little so offset gains, unless you are leaving the pump at home. All the guys spending a fortune to shave off a few grams is a bit over the top, unless you are a top level pro. Take a dump before heading out, or get a hair cut and you could save a fortune!

Are you guys pumping schrader or presta at the petrol stations? I have a presta adaptor but can never get it to register the pressure right, is there a trick to it? or does it only work right on schrader.

garo

Get a proper frame pump. I have a Zefal HPX3 - bought for 30 Euros - and punctures don't bother me anymore.

blorg

I'm not sure the Irish petrol station pumps register pressure well at all in general. OK for a car but I don't know that they are reliable at the higher bike pressures. I am generally pumping presta with an adapter.

I've pumped at petrol stations in Spain and they seemed to register the pressure much better. The gauge is somewhere else too that is much easier to see/use, can't remember exactly where.

Personally I find a small hand pump sufficient for the unlikely event that I might get a puncture and have never got a pinch flat due to insufficient pressure. Finish it off at a petrol station or at home later. This is with 700x23 or 25 size tyres.

beans

Must get a decent frame-pump... I have braze-ons for a pump on my new frame, until then the ever-useful gaffe-tape shall be employed

garo

The Zefal does not need any braze-ons. It is spring loaded. I've done a 1000 miles with it on, taken bottles out for drinking while riding and all and never had any trouble.

Dunmoon

If you're not doin too much mileage commuting you could go for a " solid tube". This is a solid piece of rubber the same size as a tube that replaces a regular tube. You are guaranteed to get no more punctures with this one.
Only problem is you experience a really "dead" ride, no give in the wheels, and the spokes are prone to loosening with disasterous results...
Had one on the back wheel of my commute years ago, ditched it after a couple of months, mileage too high for comfort. But its an option for lesser miles on smooth roads.

blorg

Airless tyres are really not a good idea at all. You lose basically all the cushioning effect of a pneumatic tyre and risk wheel damage which is a lot more serious than a puncture. It's perfectly possible to get virtually puncture-proof pneumatic tyres these days (I have over 10,000 km between punctures) which will ride a hell of a lot better.

As the late great Sheldon Brown said:

Of all the inventions that came out of the bicycle industry, probably none is as important and useful as Dr. Dunlop's pneumatic tire.

Airless tires have been obsolete for over a century, but crackpot "inventors" keep trying to bring them back. They are heavy, slow and give a harsh ride. They are also likely to cause wheel damage, due to their poor cushioning ability. A pneumatic tire uses all of the air in the whole tube as a shock absorber, while foam-type "airless" tires/tubes only use the air in the immediate area of impact.

Airless tire schemes have also been used by con artists to gull unsuspecting investors. My advice is to avoid this long-obsolete system.