im thinking about getting my cases and cylinder powder coated while i have my bottom end apart. but im worried about them warping. has anyone had any experience with this or knowledge of the cases warping after powder coat or the cylinder and head warping. i just want to be 100% sure theyre not going to get messed up

if they warp, something wrong happened. 400F isn't a lot of heat.

yeah the cylinder and head where my main concerns i know 400 is not that hot but when your cooking it for 20-30 min thats what concerns me. mainly the steel sleeve seperating from the aluminum cylinder. id love to here what erbe's issues where

Erbe  had a lot of problems with a cylinder maybe he will chim in

400 deg is not a lot of

if they warp, something wrong happened. 400F isn't a lot of heat.

400 deg is not a lot of heat for steel, stainless, steel, titanium for some metals.    400 deg is too much heat for aluminum.  Anything over 300 deg. aluminum's temper will be changed.  I have had a lot of thin light-weight aluminum parts ruined when they are powdered coated.  Warping is not the problem but changing the temper is a huge problem on aluminum parts.

We had to have a batch of 25 jet ski heads re-heat treated after they were powdered coated.  They were so soft that the combustion chambers would stretch (volume of the head would increase) after 5 gallons of fuel.  Head gaskets would blow in less than one week end of riding.


A customer recently brought us a set of Harley heads that he had powdered coated.  Instant head gasket problems.  We would machine the head gasket surface and a few weeks later the gasket would blow. We check the top of the cylinders and they were flat.  We would check the head gasket surface and they would have waves in them.  The customer replaced the heads .........no more head gasket problems.

Another customer had an aluminum four stroke head powder coated.   One valve seat fell out of the head and two others were starting to move.  The head had not had a problem before power coating.

Another customer had an aluminum swing arm powder coated and the swing arm started bending like it was made of  rubber.

Another customer that makes cast aluminum patio furniture had a large batch powder coated.  It turned it all soft and would bend when you sat it it.

I can keep the list going but I do not have time to list all of the different aluminum parts I have seen the heat treat ruined when it was powder coated.

I have seen some aluminum parts powdered coated that did not seem to have a problem but this is the exception not the normal pattern of powdered coated aluminum parts. 

The problem with power coating shops is they are not metallurgist and do not understand the effects that heat and the amount of time a object spends at certain temperatures has on the heat treat of the part.  Different metals respond to  temperature differently than others.  Some metals melt at temperatures under 500 deg.

Are you willing to take the chance of ruining parts that are discontinued or hard to find ruined by a powder coat shop that says it will not hurt your aluminum cases?

well that pretty much sums it up for me. ill just stick to painting them. and put the money somewhere else on the LT.  thanks for the info

Man I hope your wrong. Lol I had everything besides motor and frame on my Zilla powder coated including my swinger. This is gonna suck I finally get it together and then have problems with it bc of powder coat.that blows.I hope I get lucky with mine like I did with the wife's bc her head, cylinder, and stator cover were done and been fine since so let's hope for the best.

I think it depends upon the powder and the time that it is cooked.  I have been told that the good powder requires higher heat and a longer baking time.

Most cases are cast aluminum and usually not tempered.

So why has lot of people with banshees powder coat their engines without issues?