Seet, what you see is stains on the aluminium. I use a babies bottle brush, That's the best I can come up with. Nothing is going to clean those parts the way you would like. One thing you can try is Mr Sheen and a pair of stockings /pantyhose. Spray the Mr Sheen and run the panty hose around the area behind the disc and spin the wheel. Won't be prefect but might get some of the staining off, also will seal the ally as well. Just be a bit careful with the discs on the first braking use after doing that.

Might give it a go myself as I just thought of that.

I think it's rained 5 out of the last 6 times I've been riding lately!

Does anyone know of something I can spray on my boots to waterproof them?

I dont cover any thing before i wash the bike, but it is pretty much stock. Covering the pod style air filters is a wise thing to do, but a shopping bag would do. I use a 'gurney' to get the dirt out of the rough cast alloy bits ( rear wheel and crank/gear box cases ) , but no high pressure water goes any where else. if I have to use detergents then it is a 100ml per 9 litre bucket. That is mainly used after a ride in which I have hit bugs , other wise it is water only.
Two tricks, my lady will wash and wipe the bike down with Enjo cloths, and polish the painted parts with some sort of Enjo cream, and the seats get some other Enjo cream applied. But first I usually hit the bike with a good soak of fresh water and blow the water off with a garden blower . Then I go around all the foot lever and controls, lever points, cables etc and hit them a very light touch of lanolin spray oil/grease.

Polished alloy bits that get a bit stained are hit with Silvo, and then followed up with chrome/alloy polish ( I use Ratheon , which is no longer available) . I also do the spokes and wheel hubs the same way.
The engine is started and let get hot (about 5 minutes) and then the bike is put away with a soft towel over the seat and fuel tank, and then a bike cover over all of that. (yes, the cover is put on over a warm bike)

Meguires once a year as long as the lady is not around ( she is an Enjo nazi).

 To wash my bike (only when NEEDED), I go over it with bug'n tar remover where needed, then I paint only the motor (grey alloy) and rear wheel (textured surface) with liquid laundry detergent (Dynamo, no fabric softner, mixed with a little water to make a runny paste) then let dry in the sun until blue paste turns white and powdery (this process lifts and cleans any oil, grease and road grim), time for a beer or two. Then hose off, then cap full of wash'n wax in a bucket of warm water, with a soft wash sponge, suds up the rest of the bike (in the shade) then hose off, then blow off with compressed air, paying special attention to all switch blocks and bolt / spark plug cavities.

To detail (only when NEEDED, usually after third or fourth wash)... now that's a longer and more energy required process. Bike lift, good paint wax/polish for all painted surfaces, wax on using old towel ripped up, polish off using a clean micro cloth and effort (fast but not heavy), all chrome and alloy ('cept motor) and rear wheel (polished sections only)  I use Autosol metal polish with a clean micro cloth. For the spokes, front axle I rub on with fingers then I use long strips of cotton cloth wraped/looped around once and a sawing action (takes a bit of practice to get right) to polish off (and any other round parts, eg; forks, frame ect). Leather cream/conditioner for leather, Armor all for all plastics and rubbers (NOT hand grips, foot pegs or tyres).

I give mine a good hose, wait for it to half dry them wipe it down with a towel.

If I've done a lot of wet weather riding during the week,  I hose it first, then wash it with dish washer in a bucket, then  hose that off then wait till its half dry and towel it down.

Moist rag and old shirt.....!   You may as well start using sandpaper.  Your bike though!

Moist rag and old shirt.....!   You may as well start using sandpaper.  Your bike though!

Ol mate knows a thing about paint and paint correction/care, forums are good like that ;)

https://www.kiwicare.com/en-gb/products/kiwi-rain-and-stain-protector

Pledge does a great job as well....

Did I put that there....

remember the days as a kid with a strip of leather hanging from the hub which polished the hub as the wheel turned?

Just make sure you put her pantyhose back in her drawer Seet........

and let us know what your missus said the next time she slipped those biggirl pantyhose on..... LoL

They’ve been divorced 8 years now. 

I just put my wet gear on and take it for a ride in the rain

All do your self a favour and look up the bowdens way of touchless washing and drying your bikes. Washing by hand and drying by hand scratches the paintwork....swirl marks..

Do yourself a favour and stay away from Bowdens...its cheap.  

Have been checking out AMMO NYC for awhile now. Has some great tips on his channel.