Australian Cycling Forums - Bicycles Network Australia

Mulger bill wrote: Pity about the metal cap availability, will suss out ebay.

Shaun

I sent Mulger Bill a link to these & somebody in Australia won them. Was it you mate?

I wish. Me bloody new paypal account wasn't thru in time for the end Thanks for the tip Chris.

I've saved a search tho' *Fingers crossed*

Shaun

Hilary Stone in the UK seem to have them from time to time, so they do turn up with some degree of frequency.

Better luck next time.

I bought a patch kit and attempted to fix the puncture last night but it didn't work. Basically it couldn't stop air from leaking. Strangely the kit doesn't come with any instructions.

I started off by sanding the surrounding area, then applied the glue followed by the patch itself. Tested it after 30 minutes, I can still hear air leaking out from that spot.

Maybe I applied wrong side of the patch, is it the side with silver backing or transparent backing that supposed to kiss the hole?

After applying a thin layer of vulcanizing agent (glue) to the tube, you need to wait until it's touch dry (3-5mins). Only then can you apply the patch, along with very firm pressure for a minute or so. Some people keep that pressure up for longer time before testing.

Put your tube under water and test it. Identify exactly where the leak is coming from.

peter wrote:I bought a patch kit and attempted to fix the puncture last night but it didn't work. Basically it couldn't stop air from leaking. Strangely the kit doesn't come with any instructions.

I started off by sanding the surrounding area, then applied the glue followed by the patch itself. Tested it after 30 minutes, I can still hear air leaking out from that spot.

Maybe I applied wrong side of the patch, is it the side with silver backing or transparent backing that supposed to kiss the hole?

Peel the foil off before applying the patch - the plastic can be left on the patch to help prevent the excess glue sticking to the tyre

Mike

peter wrote:I bought a patch kit and attempted to fix the puncture last night but it didn't work. Basically it couldn't stop air from leaking. Strangely the kit doesn't come with any instructions.

I started off by sanding the surrounding area, then applied the glue followed by the patch itself. Tested it after 30 minutes, I can still hear air leaking out from that spot.

Maybe I applied wrong side of the patch, is it the side with silver backing or transparent backing that supposed to kiss the hole?

Start by *lightly* sanding the area around the hole.

Apply a coat of the cement around the area, larger than the patch not too thick, smear it out with your fingers. Wait until it is dry/tacky to the touch (30 seconds or so usually), you're ready to apply the patch.

Remove the silver foil, leave the clear plastic on. Press the patch firmly over the puncture, with the clear plastic facing up. Once this is done, leave it for a good five minutes or so, the patch will vulcanise with the tube and becomes permanent.

You can leave the clear plastic on (won't do any harm), or if you wait for the patch to set properly you can peel it off as the patch will be firmly set onto the tube.

Cheers! Have to re-try tonight.

peter wrote:Cheers! Have to re-try tonight.

They've said it all.

The three biggest causes of repair failure are:

- not letting the glue dry before applying the patch
- putting too much glue on (surface dries, not underneath)
- not patching the only hole

Of course, pinching the tube when putting the whole thing back together again is fairly popular too

Richard

Many tubes have mould ridges that can let air escape along them under the patch if you don't press down hard or long enough, easy to check out if you do the Sogood test.

Shaun

After following the instructions to the letter, apply the patch & use the convex face of one end of a tyre lever to firmly rub across the top of the patch, Start at the middle & work your way outward as if you were trying to expell an air bubble in the glue.

Rub lengthwise then crosswise, but keep a firm pressure on the tyre lever. This will help to ensure that the entire surface of the patch is firmly stuck to the tube, ensuring a successfull repair. This is a trick that my stepfather taught me when I was about 10 or so. Once it's done, apply a little french chalk [or talc] to the surface of the patch, or the whole tube, to ensure that any residual stickum does not glue the tube to the inside of the tyre.

There should be no raised ridges or mould lines in the immediate area of the hole because these will have been abraded away when correctly preparing the surface of the tube before gluing [as per the instructions]. Once the patch is on, & firmly pressed in place, there should be a perfect seal at the injury point, but firm rubbing with the tyre lever will also ensure a proper seal at the raised ridges too.

The second try was all good! The step I missed was too much glue and didn't wait for it to dry.

Now I wonder how do you put the tiny rubber tube inside the valve, can you dismantle the valve easily (or require special tool)?

peter wrote: Now I wonder how do you put the tiny rubber tube inside the valve, can you dismantle the valve easily (or require special tool)?

The surgical rubber tube is for Woods or Dunlop valves. it is not needed for schrader (car type) nor presta valves.

See the several other threads which has discussed the little rubber tube found in patch kits.

Mike

Great! Another 0.1g I don't have to carry