Painting plastics

[xthumper]

I want to deepen and darken the colour of the paintwork on my bike but apart from the tank all the other panels are plastic.
I assume they are the same colour all the way through and not just painted.

I have done a bit of research online and understand I would need to clean the parts thoroughly, sandpaper them, use adhesive promotor, 2 primer coats, 3 paint coats, 2 clear coats.

Has anyone here experince in painting mototcycle plastics?
I don't want to bother if it is going to flake, crack and peal in a short time.

[digitalcaptive]

It all depends on what type of plastics you're painting, Thermoplastic polyolefin is widely used in flexible automotive exterior Typically adhesion promoters are applied followed by a primer (my prefered primer is an Alt and Weinberg APS-3 and I believe Trimite do their own version of APS-3 I prefer these primers as I still like to key my primers rather than go wet on wet as some painters do)now you are ready for your basecoat/colour, if using a metallic or pearl use a slow solvant/ if solid colour then something a little faster (stick with solvant bases unless you have a spray booth with significant air movement then you can think about a water base) finally top it all off with a nice 3 coats of an elastomeric 2K Clearcoat the flex in this will promote adhesion and stop cracking/flaking...........

Altenatively get a can of smoothrite and hope for the best

[Zenarchy]

On my africa twin, I think the plastics are painted (on the bigger parts at least the plastic underneath appears to be black, but my bike is white).

I'm don't really know anything about the XT, but I think on some of those types of dirt bikes, they have a different softer type of plastic, where the colour is actually in the plastic itself and it doesn't have a painted finish over the top (though I could be wrong?).

If that's the case, then vinyl dye might be worth a look (though I would try to find out if the colour is IN the plastic first and whether it'll work with that type of plastic, and do a test on some hidden area first to avoid ruining them).

I used black vinyl dye to blacken some of the plastic parts on my bike and they came up like new (chainguards, mirrors etc.). If you do a search for 'vinyl dye' here you'll find a thread with some pictures in and my experience of how it worked.

There are lots of similar products, but there was only one I found (from a company called US Automotive) in the UK that actually dyed them properly. Most of them just put a layer over the top that rubs or wears off over time. The stuff I used, actually sinks into the plastic itself and colours it properly (and doesn't appear to have faded or rubbed off at all).

If you used that approach,then it might be a bit of a pain to match up the other parts of the bike you want painted in the same colour, but then the dye might be more durable than paint (as it sinks in and won't crack or flake off as the colour sinks into the plastic itself somehow).

[xthumper]

Thanks for the detailed replies.
As to the type of plastics they are, I have no idea.
It is an XT600E 03.

The 2 mudguards, 2 side panels and headlight cowling when held up to the light look to me as if they are blue all the way through and not painted. I am pretty sure of this.
To get the side panels off (which is done quite often to get at other parts) it takes a bit of pulling and pushing so I was concerned paint would crack there.
Vinyl dye is very interesting and something I had never heard of before.
But like you say it migh tbe difficult to match the tank with the same shade.

[Zenarchy]

If you try the vinyl dye it's important to get one that actually penetrates (similar products that claim to do the same thing seem not to and just leave a crappy coating that wears off).

I think this is the stuff that I used:

USAutomotive - The UK number one supplier of American Car Parts

They have a few different colours including some gloss ones (more are available in the US I think). In America there seem to be a few different products like this from different manufacturers, but that was the only one I could find in the UK that actually penetrated the plastic.

If you do a google search for 'vinyl dye' you'll find closeup photos of people who modify computer cases and cd drives etc. with it (that's how I found it) that might give you an idea of the colours and finish.

If you decide to try it, it would probably be a good idea to see if you can get hold of an old broken fairing piece in the same material and give it a try on that first then see how easy it is to get it colour matched (and that it actually works well enough for you).

I have no idea how it'd work on fairings myself, but it worked a treat on the black back mudguard on my africa twin, on the chain guard, and other black plastic parts that are black all the way through. A single can went surprisingly far so you probably don't need much of it, and there was no prep work apart from making sure the parts were properly clean (no sandpapering or anything as it retains the original finish).

Needs to be done in a well ventilated area, that's above a certain temperature though (if you do it inside be careful and wear a mask!).

[xthumper]

Thanks again.
I do have an old XT plastic mudguard that I can practise on.

I e-mailed a couple of companies and asked if the VHT penetrating colour dye would be suitable for using on plastic motorcycle panels. One replied and said no, "this product is intended for interior seating & vinyl panels".

But as you successfully dyed some black plastic on your bike I might give it a go anyway and while I am at it I could use some of that black gloss myself and some chrome plus plate finish too.

[Zenarchy]

I think that was the stuff that I used. I'll see if I still have the empty tin somewhere so I can be sure.

It worked great on the black plastic parts of my africa twin (and that's not vinyl as far as I know).

If you have a look here:

linear1 case mods » I’m high on vinyl dye

I think that was one of the original links I saw before buying the VHT stuff (though they used a plastikote one and plastikote sell something similar in the UK but that isn't exactly the same and doesn't soak in like that so you need to be careful to get the right one if you get a plastikote product).

There are tons of pictures and accounts like that of people painting computer equipment (which as far as I know isn't vinyl either - though I may be mistaken).

When I was searching for that, I came across this link:

VinylDye.co.uk Colour Plastic, Leather and Textiles

That seems to have a bigger range of colours (looks like someone has started capitalising on the lack of those products in the UK - took me ages to find one and us automotive were the only ones I could find at the time I looked).

They seem to have a colour matching service there too (though I'm not sure how well that works or how good their products are as I only used the VHT stuff myself and it was only black).

Some of their examples look like it's done a good job though (even turning black plastic to white in one case). If you've got a spare part to practice on first to make sure you're happy and it's durable enough, might be worth a try perhaps.