To powdercoat or not to powdercoat?

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Jan 13, 2006
The motor. Now before you all get on the "powdercoating holds in heat" bandwagon, I would like to hear well thought out opinions. My first thought is that Harley Davidson powdercoats half of their engines and the other half are chromed. I'm not sure which is worse, they're both bad at dissapating heat. The harley davidson motor is also about the most arcaich (Yeah, I know it's spelled wrong) of motor designs and they are also air cooled. Apples to Apples? Do Nortons run notoriously hot? Kick it around, tell me what you think.
Were talking bar hopper here, As long as your runnin from stool to stool. with the shinny objecks crowd I would see no problem with the plastic beads. But if your like riding for more than three hours in a row you may need to think about this a bit. norbsa
Powder coated cylinder

Check the techical aspects from Conrad heatsink website below. It states this company chooses polyester resin (powder coating) as standard for their heatsinks. Also note thermal resistance decreases with increase in temperature. That means the hotter the heatsink gets the better it dissapates heat.
Conrad website

I clicked on the URL and it didn't open. Go to Conrad main page then click on "technical".
Thick or thin, that is the question

There are as many powder coatings as there are paint coatings. It also depends on how it's applied. Factories can use whatever they want to get the results they need. If you go to the cornerstore powder coater, and powder coat your cylinders you are going to get very well insulated cylinders. I use Gunkote, coatings for any areas that need good heat removal. I will challenge any powder coat or paint ,or bare untreated metal to remove heat from a heat source as well as Gunkote. Thats how much I like this stuff.
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Yeah, it's gonna be a barhopper. I know, sacrelige. Be that as it may, my other thought was anodizing the cases and head but then the problem is how to match the cases and head to the barrel. That's why I wanted to talk about powdercoat. I will check your links and get learn-ed. Awesome responses. I'm used to getting sophomoric responses from people who would rather give opinion rather than think out their answer and applya little common sense.
Big Jake,
I work as a chemist for the company that supplies the powder coating to Harley (PPG). Jimbo hit the nail on the head. It will depend on the chemistry of the powder applied AND the thickness of the film. As in any paint job, preparation is crucial. The Norton castings are notoriously porous. Oil and dirt will be deep in the pores. Blasting, solvent washing (vapor blasting?) and washing again will be necessary as adhesion can be a big problem in powder coating. Choose your powder coater carefully.

Norton motors do not run excessively hot. Under most circumstances an oil cooler is not even necessary. I know cases where an oil cooler with thermostat was mounted and the thermostat rarely opens. If the motor is relatively stock and you choose the right powder and coater, you should not have any problem.
Most my pals who ride Nortons ride there bikes enough to get caught in the rain. Have you ever had to clean a bikes motor that has been splashed with muddy water while hot? Annodizing motor cases? look no further than your typical 70's Jap bike, bad idea. kind of like chroming alloy engine covers looks taddy soon enough. norbsa
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