Cali' 3, caliper nipple won't seal.

Thought I’d give the bike a treat and change the brake fluid.

Now the left hand linked disc won’t seal on the nipple.

Removed the caliper, now suspended on the handlebars.

Sealing face on nipple looks a bit rough. But, not having scrutinised one before, this might be OK? I work in QC, in a company that makes prosthetic legs. The sealing faces on some of our components mimics that of the caliper / nipple sealing surfaces, so I know what I’m looking for.

But, the sealing face in the caliper has a slight nick in it :unamused:

The angles between the two , are I’m “fairly” sure are not the same angle.

I could take the caliper to work and “Plastiform” the thread and sealing face to make sure.
Plastiform is a twin pack fluid that flows easily and takes the form of the component that it is used on. Once it’s set, it is extracted. It’s flexible enough to remove without damaging the form which needs to be inspected. Then measure the angle on our Starret VMM. ( visual measuring machine)

Then attempt to recut the seat by hand, this has successfully been done at work.

Hmm, repair kits are available, beats faffing about. :slightly_smiling_face: £7.99

I’d be tempted to get a bit of wooden dowel which is a good fit in the nipple hole and copy the taper from a known good bleed nipple and using some fine grinding paste or even autosol metal polish I would lap the sealing face at the bottom of the hole in the caliper, a bit old school maintenance fitter but it’s not much different to what we used to do with steam safety valves on big old boilers and at the end of the day it’s not going to remove much material leaving the recutting option for afterwards if it still doesn’t seal :grimacing:

I worked for Saacke 12 years ago, before being made redundant. I’m a bit familiar with boilers, well, more the burners actually. Currently used some PTFE tape, which seems to be holding.

6" diameter nominal bore pipe for big burners as a gas supply.!!!

I have a large S/S atomiser cup in my garden as an ornament. :rofl:

I’m quite sad too and have the pair of bronze seats out of a 6” duplex safety valve as candle holders on the hearth of the fireplace, we may have met if you ever worked in the Leeds area, 35 years of big scale steam & mphw district systems at St James’s hospital and Bradford Uni.
You know just tightening the bleed nipple down hard a few times would probably work too, depends how deep the gouge is I suppose :grimacing:

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PTFE tape seems to be holding.

Ordered the repair kit anyway, as a back up.

I might have gone to St. James’ with our auditor, pre 2010.

I had the same issue on the T3 in Germany on route to Italy and found a Moto Guzzi workshop who had spares. Mechanic fitted a replacement nipple in stainless steel but warned if the seating in the caliper was worn/damaged rather than the nipple it would continue to leak. In the event it didn’t and 40,000 on it is still sealing OK.

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