Park Tool Self Adhesive Puncture Repair Patches...

carrotcruncher

Anyone use these and find they work ?

Are they meant to be a proper fix or just a 'get you home' remedy ?

I've now repaired the same puncture 3 times.

All seems ok, no evidence of air escaping - put tyre back on bike, pump up to appropriate pressure and by morning come back down to a flat tyre.

Ok, first time I thought I'd maybe got something wrong, or indeed missed a small sharp object that was re-puncturing every time - but it isn't - they simply don't seem to be able the withstand the pressure when fully inflated in the tyre.

They just peel off when I get the tube off again to repair.

Tried applying a patch with no air in the tube, with some air in, with lots of air in to see if theres any hidden secret, but the result is the same.

Bad batch ? are they not really very good ? have I missed something obvious ?

Cheers

asprilla

I use them as a perm repair. Not had an problems with them so far.

Wallace1492

These are brilliant. I have used on road and MTB with never a problem. Quick, strong and permanent repair. You must have had bad batch or not done it right.

spen666

As per the other replies. I use them as permanent repairs

My only gripe is they put the price of them up massively about a year ago

carrotcruncher

Got a reply from park which I've copied in below - may help anyone else in the future anyway :

Thanks for the letter you sent regarding your experience with the GP-2 Pre-Glued Patches. Our goal is to make the patches 100% effective. While the patch has proven to be very effective, based on the experience you’ve had, we are not to that point yet.

Our experience with the patch over the past few years shows there are basically four factors that lead to patch failure.

The first is when the tube is scuffed too aggressively with the sandpaper. When the tube is scuffed too aggressively or for too long, tiny grooves are formed—grooves too deep for the adhesive to flow into and seal off. As a result, air can escape. It just takes a couple of light swipes with the sandpaper.

The second source of failure is a tube that is not clean and/or dry. If there is any dirt, talc, or tube residue left after sanding, the patch will adhere to that dirt or talc rather than the tube. Likewise, if there is any moisture on the tube, it will get trapped between the patch and the tube. To insure the tube is dry, quickly wipe it with a damp piece of cloth and let it dry. Then apply the patch, making sure there are no wrinkles in the patch material.

The third source of failure is when the hole in the tube is directly on, or next to a seam. In this case, there is not enough surface area around the hole for the patch to seal against. In these situations, no patch is going to hold well.

The fourth source of failure stems from the tube to tire width compatibility. If the tube is too narrow for the tire, it will stretch too much and this may stress the patch bond.

As to testing, it is best to install the tube into the tire and inflate, and then wait. The tire holds the patch tight to the tube.



I think my problem was the proximity to a seam, where just a small portion of the patch had to overlap.
Anyway, I've replaced the tube now and all is well.

Salsamander

Thanks a through reply, I'm impressed.

Also I have to say I've never had a problem with them, I think they're great