Tiny leak after new tyres fitted

[Freddyfruitba...]

I had my (tubeless) tyres changed about 4 weeks ago, by my usual independent mechanic. Ever since then, I’ve noticed a very slight fall in pressure on the rear. We’re talking about 0.5-1.0 PSI per week, where previously, there was no discernible leakage at all. I've checked the wheel/tyre/valve with soapy water, but no dice.

It’s just a bit irritating, especially knowing I’ll have to put up with this for the lifetime of the tyre. I’m assuming there’s an imperfect seal on the rim? Would it be unreasonable to go back and ask to have it refitted? Or is this level of leakage considered ‘normal’?
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KC100->CB100N->CB250RS--------->DL650AL2->R1200RS->R1250RS

[panrider_uk]

I'd say no leakage is normal.

Neither my Guzzi nor my Volvo have ever lost any tyre pressure.

I'd have them refitted for peace of mind.
A small leak becoming a big leak at speed wouldn't be fun.
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Current bikes: Honda ST1100 Pan European. Moto Guzzi V85 TT Travel

[Islander]

[stinkwheel]

If it was me, I'd replace the valve cores, re-inflate them to about 10psi over normal then let them back down to the normal pressure.

Evens chance it's either a slightly leaky valve core or the bead isn't quite properly seated, this would potentially fix both.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[A100man]

One of the guys I use routinely replaces the entire valve..

As an occasional rider I wouldn't worry about it, since I'll generally check before going out. A couple of strokes on a stirrup pump will give you 1 psi.
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Now: A100, GT250A, XJ598, FZ750, SL1000

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600, Skorpion

[sickpup]