Repair glass cut

[Thornyone]

(I think that this issue has probably been covered before, but though I’ve tried a search, I haven’t found a post). Today I had to mend a puncture in my “puncture proof” Schwalbe Marathon rear (inevitably) tyre. The tyres still have plenty of tread and good sidewalls but there are quite a few cuts from which I removed glass shards, the longest maybe 3mm. The Greenguard layer can be glimpsed at the bottom of the hole from which I fished out the glass. I wonder if there is anything which works to fill in the holes? If I replaced the tyre I could well end up with similar holes in a matter of days given the state of roads/paths round here.

[alexnharvey]

Would you continue repairing the new holes you'll have every three days if there was a successful method?

[rotavator]

I think some people use superglue but I have never tried it myself.

[RickH]

When I bother I tend to use Loctite Powerflex it has some rubber in it so doesn't set as rigidly - "Rubber infused gel formula for extra strong and flexible bonds"

You do seem to get a lot of cuts by the sound of it. I finally got round to checking & gluing my Voyage Hypers recently after about 12 months (I took them off to put Snow Studs on for last week's wintery weather) & found 3 small cuts in one tyre & 5 in the other. One will have been last September's puncture - a shard of fresh broken bottle that probably got kicked up by my front tyre & impaled itself in the rear. One of the others may have been a puncture in June - I never found the culprit but there must have been something sharp on a railway path we cycled on as 3 out of a group of 5 of us had a flat within the space of about a mile.

2017 was a bad year - not only did I get a puncture but I had TWO!!

[Brucey]

if the cuts go through to the carcass fabric the tyre ought to be booted but cuts in the rubber tread/guard layer are (IMHO) nothing to worry too much about.

It may look as if you might pick up fresh stones in old cuts and that this might give you punctures but this is usually a comparatively rare event, and said stones need to be sharp-edged to actually cut further into the tyre.

It is a good idea to pick stones etc out the tread every week or so anyway; you will soon see if old cuts are picking up fresh stones or not.

IME most things that you might choose to use to fill or glue tread cuts up with don't last anyway; they are more a palliative for the mind than a repair to the tyre.

cheers

[RickH]

IME most things that you might choose to use to fill or glue tread cuts up with don't last anyway; they are more a palliative for the mind than a repair to the tyre.

The Powerflex seems to last OK & it helps keep the bits out of the cuts, particularly if you frequently ride on gritty surfaces.

[Brucey]

IME most things that you might choose to use to fill or glue tread cuts up with don't last anyway; they are more a palliative for the mind than a repair to the tyre.

The Powerflex seems to last OK & it helps keep the bits out of the cuts, particularly if you frequently ride on gritty surfaces.

I feel I should point out that if your tread is ~3mm thick, there might be ~2mm of rubber over the carcass plies. A cut in this thin rubber does not flex (open and closed) a very great amount.

By contrast in an M+ tyre the rubber is 8-10mm thickness over the carcass plies. Cuts in this thicker rubber tend to flex pro-rata with thickness, i.e. perhaps x5 as much, so are (IME) far less likely to be sealed using some kind of adhesive.

cheers

[Thornyone]

Would you continue repairing the new holes you'll have every three days if there was a successful method?

I wasn’t suggesting that I get such cuts every three days, just that it would be rather annoying to get a deep cut in a brand new tyre, something that seems quite likely where I am cycling at present, and which would immediately render the tyre little better than my current ones. I would happily use a spot of some sort of glue on say a fortnightly inspection if such glue were effective. It is very annoying to find a liberal sprinkling of deepish cuts in a tyre which should otherwise have plenty of life in it.

[Thornyone]

I think some people use superglue but I have never tried it myself.

I have read that superglue, being very hard, can actually mimic a glass shard.

[Thornyone]

if the cuts go through to the carcass fabric the tyre ought to be booted but cuts in the rubber tread/guard layer are (IMHO) nothing to worry too much about.

It may look as if you might pick up fresh stones in old cuts and that this might give you punctures but this is usually a comparatively rare event, and said stones need to be sharp-edged to actually cut further into the tyre.

It is a good idea to pick stones etc out the tread every week or so anyway; you will soon see if old cuts are picking up fresh stones or not.

IME most things that you might choose to use to fill or glue tread cuts up with don't last anyway; they are more a palliative for the mind than a repair to the tyre.

cheers

Thanks. I suppose that of all the cuts there was only one where the glass had actually penetrated, and then only a pretty small hole in the inner tube. I admit that I hadn’t given the tyre a regular inspection for a while: yesterday was the first time the bike had had a wash for some weeks (after the hose pipe defrosted).

[Thornyone]

Would you continue repairing the new holes you'll have every three days if there was a successful method?

I wasn’t suggesting that I get such cuts every three days, just that it would be rather annoying to get a deep cut in a brand new tyre, something that seems quite likely where I am cycling at present, and which would immediately render the tyre little better than my current ones. I would happily use a spot of some sort of glue on say a fortnightly inspection if such glue were effective. It is very annoying to find a liberal sprinkling of deepish cuts in a tyre which should otherwise have plenty of life in it.

[mjr]

Small cuts can be melted back together on some tyres with rubber solution. Larger holes filled with Storm sure, but that power flex sounds interesting too.

[squeaker]

Black Shoe Goo has worked OK in some of my tyre tread cuts.

[reohn2]

Ive trid a few methods,flexible super glue,shoe goo,rubber solution,contact adhesive,etc,IME nothing lasts long enough to be effect.
I agree with Brucey,boot a tyre that the carcass has been breached and pick the bits out of cuts regularly,especially glass shards.
Glass shards are a demon,they're hard to spot and sometimes missed even when the tyre is deflated and cuts are opend up,the tinyiest shard is a potential puncture if ridden on continually.
Also my theory supported by experience with glass is that when say a bottle is smashed on a hard surface the point of impact sees large numbers of very small splinters/shards in a confined space of say a 200 to 300mm circle,in that area and further out are larger more easily spotted bits of broken glass.It's the smaller central area that causes all the problems for cyclists as the larger pieces of glass are easily spotted but some times a kind soul will remove the more threatening bits of glass and throw them in the hedge/canal,etc,leaving the mostly unseen small shards on the road or path.
The worst about the the small shards in a concentrated area are that there's more potntial for a bike tyre to pick up more than one shard sometimes as many as half a dozen in one concetrated area of the tyre.
The largest shard punctures the tyre but if only that shard is removed and and puncture repaired there may be other smaller bits of glass that don't puncture immediately but are driven into the tyre by riding,these bits are time bomb like which can puncture later.
The trick IME is to spend some time searching the tyre for these extra time bomb potential punctures when mending the first puncture.

[9494arnold]

Plus one for lurking glass in the tyre. Recall being in a ride when one of the group punctured. As you ought, the inside of the tyre was inspected, visually then run the finger round. (This was in the pre Puncture proof tyre era)
Also, turn the tyre inside out , this should reveal any internal splits where the glass/debris might be lurking.
Push up with tyre lever/ small screwdriver from behind the slit to see if there is anything lodged.
I have a pair of decommissioned forceps in the garage for these removals.

The victim, a welder by trade so he has pretty tough skin, ran his finger around the inner tyre and sustained a cut that entailed a visit to A and E. So do take care.

In the past I used something aimed at Tubular tyres which resembled a cross between putty and molten rubber .
Absolutely useless, used to pop out of the cut / hole on about the second revolution.