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I think powder coating is the way to go

Go for powder coating..

I'm planning on restoring a Bajaj KB 100 I just procured . The engine needs to be painted . This is what it looks like now - Engine | High Definition image #3366 view. Zoom in or zoom out high resolution photo.

What kind of paint , painting process must I choose to get a good long lasting finish . Also suggest some brand for paint if you can

Compared to paints, powder coating provides a much better finish - but durability is an issue. Any aftermarket job will not be as reliable and durable as a factory-coated engine, but you could look for some high quality paints from 3M or Nerolac.

I had an eye candy of a bike, the all black TBTS that was custom powder coated and I can tell you that powder coating is indeed the way to go. It lasts longer than regular paint and gives a cleaner finish. However do note that when you give the bike for service you can expect some paint chipping. So always keep a can of High temperature paint in hand which will help you do touch ups and keep it looking neat and tidy.

Another thing to keep in mind is to avoid splashing cold water/liquids on a powswe-coated engine when it's hot. Splashing cold water on a hot engine chips away the powder coating very fast!

That's basically due to bad coating procedure mate. If they sand down the engine properly and apply fresh primer and then coat it then the chipping can be avoided. The coat on my TBTS is still pretty intact even though its been 4 years since I had it coated and almost the entire time I had it the bike spent 70% of its time in the rain.

Yea rust also causes flaking or paint chipping. It would really help if you pay extra attention to mending the surface properly before painting. Oh and once you have it coated do not use any strong cleaning agents on the coating. I used to rub my bike down with machine oil once every month ( only on the chrome and matte surfaces ) which also helped protect the paint a lot and kept the bike looking brand spanking new

The tough part is sanding between the fins - and those are the parts where the chipping will start, if not addressed from the very beginning. Word of suggestion to the OP would be to get the coating done at a reputed paintshop and be personally present while the coating job is being done - to ensure that the minutest details are taken care of.

+1 to that. The guy who painted my bike is a friend. So he basically took care of it.

Don't ever get your bike engine or silencer painted or powder coated.
Reason.? The bikes ( Atleast most Indian bikes) at air cooled. By painting them, it is like putting a blanket over the engine. It might look better but you'll have other troubles like over heating etc.
Well, unless the paint transmits heat really well..

My suggestion, get the bore removed off the bike and get the outside cleaned really well using caustic soda or any thing which cleans as good. Make sure that you don't get even the most minute scratch on the inside. Use only plastic brushes like a toothbrush on the outside. Dont do anything to the inside.. next, If you are still not satisfied, get the metal plated. Only the outer surface again.

Hard work I know, but the best way.!

@aditya
what about the hordes of the bikes in the market which come with powder coated engines? Most of the bikes starting from a 100cc Discover to a 500cc Thunderbird come with a powder coating! The powder coating is definitely conductive and moreover the coating is not thick enough to obstruct the dissipation of heat from the fins. Imagine keeping a sheet of paper over a hot pan - will it make any difference to the rate at which the pan cools down?

Nonsense! My bike has never overheated ever and I used to ride it as close to the redline as possible when I go for highway rides. The insulation effect occurs when you apply paint over the existing paint and as a result of this laziness it ends up forming a thick coat which in turn overheats the engine. That I why I always insist on sanding down the engine covers throughly before powder coating.

Well, do you think you can get the quality of powder coat as good as the thunderbird 500? That is at a whole new lever compared to the one we can get done.
Well, it would make a difference if a pan was covered by a paper or two if it isn't stuck to the pan well. A slight air pocket formed ( if ever ) will pocket heat in it. Your bike, your wish. My suggestion is what I would have done if I was in your shoes.

Well, wasn't it a tough job.? And you have to agree that you can't sand down the engine between the fins properly and that is the place where the powder coat tends to form a thicker layer than the ends of the fins. Won't plating be much better any day.?

You could use a thick quilt or a thin pashmeena blanket, it is almost the same. It isn't the thickness of the blanket that matters but how well the blanket or bedsheet traps the air between you and the blanket.
To know whether the engine overheats or not, touching it from the outside won't make you feel the difference. You should rip your bike, then park it and after say 15 mins, remove the spark plug and check to see. Touching a person over a blanket to see if they are running a fever doesn't make sense.

It may not make too much of a difference but I am a person who things in every fine detail before doing anything. And even a small negative quality is undesirable for me. It's your bike, your wish. :thumbup:

If you insist so much on a powder coat, atleast don't go in for black..

Thanks to bbsrailfan , aeroblade and adityajohanan for their insightful replies .
The bike in question is a 1986 air cooled engine . Its in quite a messy state now , and as you can see from the pic it was painted when it came from the factory . I will be going for silver paint .

Engine | High Definition image #3366 view. Zoom in or zoom out high resolution photo.

Could sand / media blasting be used to remove the old paint ? I'm asking this as there seems to be some surface rust on some of the fins .