Paint spraying plastics.
 

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

I have done a bit of reading online and understand I would need to make sure the parts are cleaned thoroughly, sandpapered, use adhesive promotor, 2 primer coats, 3 paint coats, then 2 clear coats.

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

Hey '03XT600E'. I have done a few paint jobs myself and am a qualified spray finisher(furniture). The panels will be a standard colour and will be finished with a spray coat. Be careful when applying primer to a finished panel as you are not painting it from scratch. IME the primer contracts and cracks the top coat bad style. Also a professional finish is hard to achieve with a spray can so dont expect a grade A finish.

Try testing on a spare panel (if you have one) otherwise test a concealed area?

hope this helps.

Thanks for the reply tommy.

It does appear that the plastic panels are the same colour all the way through and not painted.
If so does the same thing apply regarding the primer?

I do have a spare plastic mudguard I can practise on.

Most plastics can be painted after using the right primer but some really can not, i aint sure how you find out though, often fuel tanks will blister and peel after a few months due to the polythene material they are made from, so if your plastics are of a polythene feel be wary.

There are additives available that allow paint to 'flex' with the plastic surface - or, at least, there used to be many moons ago. It's mixed with the paint and thinners and normally used on spoilers/wheel-arches, etc. The downside was, it could sometimes affect the finish if not used carefully. But paint technology is always advancing, so there might be something available today in a can, though I'm guessing it will be expensive.

Painting plastic is half the battle. Getting it to stay on is something else. Good luck.

paint your panels
 

hello all i have painted lots of plastic parts and i have had no problems first degrease the panels i used panel wipe but you can use plenty of soapy water.
then spray the parts with a acid etch primer this bites on to the panel then use a basic primer for 2 coats.
make sure you dont get any finger prints on the panel as this will leave a greasy mark that will let the paint lift.
when you are sure of the primer paint in thin coats till you are happy leaving each coat to dry before the next.
you will have no problems at all i was a paint sprayer for 10 years so i have a good idea what works.
i painted loads of bikes and now i have none waiting for my next

regards to all any probs just ask
el tel:thumbup1:

i refer to painted plastic fuel tanks as I had a plastic hpn 43 litre (acerbis) tank painted. (HPN sold two versions one paintable the other non - paintable) There was a price difference the paintable being a lot more expensive. I spoke to a specialist plastics/ bodywork/ Motorcycle paint shop who told me that all plastic was paintable using the right acid etch coat and to buy the cheaper version they would prime etch it. ( they thought the paintable tank would have been just pre coated at the factory for a lot more money) The tank arrived was duly etched primed painted and the job was excellent, 6 mth later bubbles appeared, they stripped it and re done the tank, it reacted again and again, they had taken advice off several primer companies none of the paint ever adhered and always reacted. it ended up having to have the tank stripped back to plain plastic. hPN advised me when I called them that the Polythene tank 9Non paint version) expands a lot under heat/cold pressure but also that the polythene material extrudes a chemical throughout its life that can not be sealed the paintable tank is made from a different plastic altogether and not just etch primed. I would assume from this that a lot of the polythen white /semi clear tanks made by acerbis are of a similar material.

As Adventure950 has found out - there is a difference with the plastics used for fuel tanks particularly. A lot of bikes these days have plastic tanks (including street bikes), but they tend to be double skinned - ie. made of different materials, the inner lining doesn't let the fuel vapours through in the same way as single skin 'polythene' off-road or aftermarket 'overland' tanks will - thus you can paint the outer surface and not get bubbles/blisters a few days/weeks/months down the line...

As El Tel explains above, it is possible to paint the other plastics (even MX style ones) with good preparation and a flexible primer - however, it is not so much getting the paint to stick while riding along, but when you drop a bike with painted plastic panels (especially dirt-bike style side panels and mudguards), the plastic tends to flex much more, and so the paint will crack and chip off?

J xx

Hi 03XT600E

Have you considered the coloured T-Cut cutting polish? If you just want to get back to the faded original colour, that could do the trick for less cash and faff - ignore the instructions though. Just get loads on and polish like you're possessed. If the plastic is coloured right through, there's no need to worry about polishing the finish away and if it doesn't work, you've given it a propper clean before you start your painting.

A fringe benefit is you end up with hugely pumped biceps - you can use the saved trip to the gym to offset the cost of the bottle of polish!

VT