Primer on top of old paint?

Question

I'm repainting my motorcycle. There a good deal of rust which I am grinding of (those 3M wheels work wonders). Do I have to remove all of the old paint too? Because there is a lot of good, unrusted surface left. Could I just leave the good old paint and put primer over it or do I have to strip the whole thing down to metal?

Answer 1

I would because some primers have a hard time bonding to paint also make shore that the surface is clean and that you use a paint prep before you put on the primer. Its also a good idea to use a rust dissolve on all of the spots that you have ground because even though you have taken off the rust it can still come back and cause the paint the bubble.

Answer 2

Yes, you can leave the old paint on there, but I assure you if you buy new paint that's the same factory color as your motorcycle, you'll notice the difference between the new paint and the old paint.

First off you want to sand off all the bad paint. Then you want to cover up all the good paint with some paper and some adhesive tape. After you sand what you want re-painted, you apply the primer. Sand it down with some high grade sand paper to get rid of all the grains. Apply one or two more coats, then you add the base coat, clear coat. Hope this helps.

Answer 3

Hi,
You don't have to strip all of the old paint, but the paint will lay down more evenly if all of the old paint is removed.
If you don't strip it all the way down make sure that the old paint is feathered and smooth

Answer 4

You don't have to strip it all the way down too metal. but you need to sand the hell out of it to rough up the surface to give the primer something to adhere to.

Answer 5

You should at least degloss the old paint. They make chemicals that can do that, or you can use sandpaper to rough it up a little bit. If the old paint is smooth and glossy, the new paint won't adhere to it as well.

Answer 6

no but you need to ruff sand it and prime the hole frame tank annd so on.