Matte plastic what to clean with

[VocalNeal]

I know. A real bike shouldn't have any black plastic but it is what it is. If it was concrete i would say it has effloresced, ie white powdery look. Not serious just not pristine and detailed.

[Susco]

I would try some silicone spray, or polish it with an upholstery cleaning product

[Agusts]

Funny enough the other day I was just putting a bit of WD-40 on a bit of metal that looked like rusted or it is going to rust, then it sprayed on some black plastic cover near the exhaust. So I just rubbed it with a rag I had in my hand and didn't think about it...

A few days later looked at the same place and notice the plastic cover part is so black, clean and shinny compared to the other section without WD-40 , I couldn't believe it....!, even after some rain here it looks like WD-40 is protected it and kept it really nice. After the next wash I'm planning to do all plastic parts with it, I recommend spray on a piece of clothes then rub it on.... (my friend also uses silicone spray...).

 

[Kwasaki]

Your find black grained plastic on many bikes I always clean mine with a degreaser and tooth brush, then apply the uv blackening stuff they use on tyres. 

 

[Neilly]

As the other guys have said, silicone spray...WD40 does work, but doesn't last as long.

 

This is the stuff I bought recently off Lazada....

 

https://www.lazada.co.th/products/crc-808-silicone-multi-purpose-silicone-spray-500ml-i8750528-s10977314.html?mp=1?

[In the jungle]

It depends on the bike.

 

If it is something like a Dream or a Wave buying the part new may well be cheaper than buying silicone spray.

 

I recently replaced an unpainted black plastic part on an old Honda Dream I have and it was 120 Baht.  My reason for replacement was not cosmetic but whatever the reason it's pretty cheap.

[Damrongsak]

Toothpaste may clean it up a bit. 

[VocalNeal]

I've been using Waxy from 7-Eleven. Just thought there maybe a magic substitute.

[alx123]

I've been using this "303 Aerospace Protectant" spray for years now and it keeps all the plastic parts of my bikes looks new. Last long as well and not greasy. I think this is originally designed for boats as a UV protectant. A single bottle last more than a year as I rarely find the need to reapply even when it's raining.