Rear Brake Feeling Off

Bike: SK3 SV650s with standard brakes

First noticed a difference straight after I had a new rear tyre put on the bike a couple weeks ago.

Rear brake feels like pressing a sponge, only slightly slowing the bike, no matter how hard I stamp on the brake. Feels very vague.

Have just used brake cleaner on the disc and pads and wiped with a clean cloth to remove any dirt / grease. Also replaced the brake fluid (which didn't have any air bubbles in)

Can anyone offer any info as to why the rear brake feels very different and weak?

Thanks,
Tim

[DJ123]

Have you serviced the calliper recently?

Not in the year that I've owned it, don't know about before

****, you use the rear brake?

Check the pads for any signs of contamination. Where did you bleed the rear brake from?

Stamp harder?

[DJ123]

I'd service the rear calliper. take it apart, clean it up. new seals and grease it up

[Mark_h]

If you've just had the rear wheel off I'd be checking that the pads weren't knocked out of place when the wheel was put back. I once managed to get both pads on the same side of the disk once. That had an interesting impact on braking efficiency.