Front brake inspection - issue found.

I was cleaning the bike thoroughly before tomorrow's show and I noticed that I have some damage to the brake

That looks anything but healthy.
Pad replacement?

They'll be fine, it's only a little bit of the edge that's broke off, probably hit by a stone or something?

Cool....it crossed my mind it was a stone or something.
I need to take the whole assembly apart anyway soon as the pads don't retract enough and they rub a tiny bit.
Or they just need a clean, something might have gotten stuck on the pad.

Reporting back.

Photo below shows the brake prior to cleaning. It wasn't the cleanest but I sorted that.
I removed all the crap from around the cylinders, pushed them all the way in to see if it's possible at all (they did go in fully) so happily I assembled everything back, screwed in, pumped the brake....tested, no change...still rubs... I gave it a few good spins while up on lift and the rubbing seems to be intermittent.

Can it be that the disc is warped? :/

The ride overall is still....hmm...gritty, for the lack of better word. When I accelerate it's no smooth...it feels weird.
I'm running out of ideas.

Regular intermittent or just intermittent?
Are the pads dirty?
Pull the pads apart and clean inside them with a long loose rag. Dirty pads can cause all sorts of silly issues.

Cleaned the pads too matey.

Intermittent regular

Is there resistance when you spin the wheel, like the brake is binding? or is it just the sound of the pads slightly touching the disc.

Hmm rather minimal...when I spin the wheel it spins, ru s and only when its really slow, it "jams" due to resistance. Not much.

Doesn't sound overly bad, I can't say without having it in front of me. I would probably be inclined to give everything a proper clean up and service. Sorry this is not an ideal thing to give advice on, We really need to feel everything to give proper advice. Sorry.

 What Dave says, If it spins feely the pistons aren't sticking, the disc will never be completely flat, you'd know if the disc was warped? your bike would judder under breaking.
spin your wheel with the bike on a jack, grab the brake then repeat a few times. if there's no resistance when the brake isn't applied? it's just the sound of your pads touching the disc slightly, which is normal.

Fair shout Dave...it would make sense for you to see/hear/feel before making a judgement.

Sim,
That's off the list then...no judder when breaking.
I don't really mind them touching slightly.... it's just the rubbing sound I hate.
Disc is gently warm after few miles...I checked few times. But I guess that's to be expected.

Not sure then about the "gritty" ride... is it possible that the guy changing the tyres overtightened the wheel and that affected the bearing? Can it affect it?

hmm gritty ride? That is unlikely to be the front spindle done up to tight as you can spin it by hand, More likely to be a contaminated front pad.

I'll give them a solid rub down then, just to rule it out.

I'm still not ruling out the wheel balancing and I'm starting to feel tempted to get it checked.
What I'll do beforehand though is take the brake off so there is nothing in the way and give the wheel a dozen spins or so and check if it stops in the same place...if it does...then it'll be proof enough (I hope) that the wheel needs balancing.

Does sound like it is fixable for the right hands, as already said hard for people to give precise advice without getting their hands on it and front brakes especially are are life or death so not worth taking chances on that you are not overly happy with

not much help but it sounds all right to me mate worst ways not much to fuss about but it wont hurt it if you get it of and clean it all up (calliper) there's a video somewhere on the site that shows changing pads and cleaning callipers if I remember right bloke runs you through it step by step

This may be way off track, Is it possible it could be a wheel bearing issue? Try spinning the wheel with the brake pads removed to see if it spins smoothly and free.

Gents,

An odd one for me.... the nuts that hold the brake in place...what size are they?
I managed to undo them with 5,5 allen key but it was rather loose. 6 on the other hand does not fit in.
Is there anything in between 5,5 and 6 sizes? I got imperial set as well and they're either too small or big.

I don't want to use 5,5 anymore because I'll knacker the bolts for sure.

Allen key? Mine are bolts that hold the caliper on, either 13 or 14 mm from memory, nothing between 5.5 and 6 in Allen keys.

Maybe a previous owner did a change of bolt there?

Darn it...always say nut when I mean bolt.

I got bolts like these (I hope the image will show)

 
And I got the sizes wrong...it was between 5 and 5,5 (not 5,5 and 6)
I reckon they're size 5 but knackered, hence loose :(
(and they're most likely different because I have the chrome cover on.)

Sorry I could be wrong but have just checked the service manual which is available here for download and it would seem to me that they have been changed to these bolts by the previous owner on the 2002 bike that is owned by Marcin's as confirmed by Simbo's post from normal bolts (could be wrong) and the torque they are put in at is 28 Ib-ft. could someone please check their bike please for Marcin

which would make sense as mine is K2.

Torque...hmm...I torqued them alright...until I couldn't no more