Can you patch tyres?

[mnichols]

I got through 3 tyres on a recent tour of Spain due to poor road conditions (sharp gravel). Two were brand new Continental GP4s. They are still in good condition other than each have a small puncture hole. One is big enough for the tube to boil out. Can the tyres be patched, or do I have to throw them away?

I road with a tyre boot for a while, but I think this eventually rubbed on the inner tube and repunctured it. The other tyre with the hole repunctured a couple of times - it just wasn't up to the road conditions but would be fine as a U.K. Summer tyre

[meic]

Yes.
I have patched them a few times. Sometimes you can get away with using an innertube patch if the hole is small. Often you need something which has reinforcing fibres in it and is a bit stronger.

My tiny supply of patch came in a Lidl saddlebag tool kit.

This patch claims to be adhesive and suitable for tubeless tyres even.
http://www.wiggle.co.uk/park-tool-emerg ... oot-patch/

However if the fibres in the tyre are too badly cut then the tyre will start to egg and eventually fail.

[Brucey]

I've been experimenting with fabric cut from an old umbrella, seems to work OK if you use several layers.

cheers

[meic]

Are you bonding the umbrella material to the tyre or just wrapping it in place?

[mjr]

I got through 3 tyres on a recent tour of Spain due to poor road conditions (sharp gravel). Two were brand new Continental GP4s. They are still in good condition other than each have a small puncture hole. One is big enough for the tube to boil out. Can the tyres be patched, or do I have to throw them away?

I'd not use the tube-escaping one except as a last resort, but very small holes can be stuck shut / filled in with something like Stormsure. It's not as good as the original compound but it seems OK to stop tyres plucking more sharps off the road. In my experience, it takes far longer to cure than the stated 24 hours.

[Vorpal]

I might try returning them under warranty. I wouldn't be too happy about holes in new tyres, whatever the condition of the roads.

Otheriwse, I would probably replace them.

I used to repair tyres sometimes. If it's big enough for the tube to bulge out, the fibres have been damaged and it's likely to fail at some point. You might be able to sew it with sail thread or fishing line, then fill in the repair with silicon sealant.

[freeflow]

This patch claims to be adhesive and suitable for tubeless tyres even.
http://www.wiggle.co.uk/park-tool-emerg ... oot-patch/

This is the type of boot that cuts into inner tubes in very short order. I have had innertubes with rectangular cuts on them from the use of such boots.

A couple of layers of gorilla tape on the inside of the tyre is as good as anything to stop the inner tube bulging if this is needed. Shoe goo to fill the holes for aesthetics. Its not really possible to glue the edges of a cut tyre back together again.

[meic]

and it's likely to fail at some point.

But not rapidly. Plenty of warning when fibres are failing.
I have patched 3 tyres in this way as they were still in early days and they all lived to be worn out.
I have patched the perished sidewalls of aged Pasellas but that wasnt just fixing a hole, it was collapsing tyres generally and they got binned. I patched them with a bit of rim tape, which worked quite well apart from only staying sticky for the first application.

[Brucey]

Are you bonding the umbrella material to the tyre or just wrapping it in place?

I've been gluing it in place but that isn't really necessary. The main advantage of gluing is that the boot stays put so is a more permanent repair. I've been using three layers of increasing size which gives a nice taper to the repair; even three layers of the fabric is only 0.25mm thickness, and even the lightest inner tubes won't be damaged by the edge of the boot.

The warp and weft in the boot plies need to be aligned with the tyre plies if the boot is to move with the tyre properly.

Three layers seems strong enough for almost any get-you-home repair and in most instances is OK for more prolonged use. However there is nothing to stop you from using more layers if you want.

The toughest repair so far has been a ~10mm off-centre slash in the carcass which was at ~45 degrees i.e. aligned with the tyre plies. This area would see very severe shear loadings as the tyre deforms against the road. This repair lasted about 400 miles before the boot (3 layers) split. Amazingly the edges of the split were kind to the tube and the tyre didn't go down. I re-repaired that with four layers of fabric and I added a rubber patch between the boot and the carcass. This caused more initial swelling in the repaired area but this repair has lasted about 300 miles with no signs of further trouble thus far.

BTW several of my chums have enquired whether I am so skint that I can't afford decent tyres any more, and have kindly offered me various tyres....

I'm not quite sure if they have believed me when I tell them that just now I want to be riding around on damaged tyres, all in the pursuit of knowledge.... but how else am I supposed to demonstrate whether something new and different is actually going to work or not....? This sort of repair is exactly the sort of thing that can make a tyre failure on tour something that just isn't a big worry any more. I've previously had tyres fail, fitted my spare, and then I haven't got a spare any more..... if I can get a more reliable booting system, I might be able to do away with having to carry a spare at all.

cheers

[thirdcrank]

My first emergency boot - as a teenager too idle to check tyres before setting off on tour - was made from some tarp-type material salvaged from fly-tipping near the Devil's Beef Tub. The technique I thought of then was to line the cover with enough of the material to hang a bit out of either side so that when the tyre was inflated the bead kept the boot in place. Surplus to be trimmed to avoid fouling the brakes. Decades later, I did something similar when I gashed a tyre rather nearer home in Shipley; repairing to Ellis Briggs, it dawned on me that although they did open on Sundays (unlike bike shops in the Scottish Borders 50+ years ago) they weren't open first thing in the morning. I improvised another boot with a couple of inches of red barrier tape liberated from some roadworks.

The shortcoming of that approach is that the thin canvas-type material has limited resistance to friction if the hole is any size.

If I was going on some TV programme for budding inventors, I'd think along the lines of a section of slick tyre with skin sidewalls. It would need to be the right width with the bead trimmed off to trap between the bead of the holed tye and the rim so the experimental stage might involve cutting up a lot of tyres. If it worked - and I'm pretty confident it would - somebody could publish a chart showing which size tyre was needed to supply boots for others of different sizes.

I'm sure I've posted before that devising cunning plans is a sign of long hours in the saddle trying to ignore the inevitable headwind.
(I wonder why "repair" used to be a synonym for "go." )

[ferrit worrier]

In the old (circa 1960s) puncture kits there was a piece of rubberised fabric , i had piece of this up to a year ago but it went missing after i used it. Sadley it's no longer included in the kits

[bertgrower]

I got through 3 tyres on a recent tour of Spain due to poor road conditions (sharp gravel). Two were brand new Continental GP4s. They are still in good condition other than each have a small puncture hole. One is big enough for the tube to boil out. Can the tyres be patched, or do I have to throw them away?

I road with a tyre boot for a while, but I think this eventually rubbed on the inner tube and repunctured it. The other tyre with the hole repunctured a couple of times - it just wasn't up to the road conditions but would be fine as a U.K. Summer tyre

Get one old light weight tubular tyres remove fabric side walls and cut to say 4-inch-long and place between inner tube and tyre.

This will work for a long time.

[Buk]

Pure speculation here. ***Don't rely on this until someone has tried it!***

The thought that keeps running through my head is that keeping a piece of gaffer tape and a packet of Sugru in your kit would be very compact.

Gaffer tape on the inside and Sugru to fill the hole. The 24 hour cure time might be a problem though it does seem to get pretty well cured after an hour.

Just a thought.

[Abu Milhem]

You certainly can patch tyres very effectively. I do regularly for tyres up to 5-6 bar. The secret is to use Velox rim tape on the inside of the tyre. Cut a small rectangular patch, chamfer the corners; prime with patch glue and let dry. Then apply glue to the inside of the casing and proceed as with a tube patch. Actually any densely woven textile in cotton or polycotton will do the job as will recycled Velox rim tape. I have use the pocket flap from a pair of terylene shorts in desperation before; it worked fine. Keep a length of Velox with you and a sharp knife/ scissors.

[mnichols]

Thanks for all the ideas. There seems to be a commonality among the suggestions that will allow me ferret around the shed and see what I've got to do the job