Cleaning aluminum drive line case, engine parts, etc.

[deancox]

I am having pretty good luck with a scotchbrite pad soaked with WD-40 and just rubbing it by hand. The surfaces are slightly pebbled and I am not looking to remove that or go much beyond a satin finish.

Does cleaning it this way make it any more "porous" or likely to get dirty more quickly in a way that can't be corrected by repeating the process?

[Bruce_C]

I use Simple Green cut with 50% water and scour with a plastic kitchen scrub brush. Have excellent results, but I started with a very clean bike.
Bruce C :)

[deancox]

.....started with a very clean bike.
Bruce C :)

Not me! See the thread about the K75C cleanup project....it is very crusty!

[dlearl476]

Does cleaning it this way make it any more "porous" or likely to get dirty more quickly in a way that can't be corrected by repeating the process?

I wouldn't say it will make it any more porous, actually using Scotchbrite will eventually make it "polished". Probably not in your lifetime but that depends on how you "scrub". As for the WD-40, I would think the bit of lube that is left once the transport evaporates would collect dirt more than a clean surface, but you said "corrected by repeating the process". Yes, that will correct it IMHO but I would wonder how often you would want to repeat the process.

Personally, I've had great luck with Wurth Brake Cleaner and an organic bristled brush. Stains and hard to remove spots (ie: caked on oil/road grime) I use a brass brush. And lately I've began using some Orange citrus degreaser (Orange Blast Auto) with great results.
As for simpole green, be careful. You can easily get oxidation on aluminum alloys that's very difficult to remove. From the Simple Green website:

"Aluminum - Is it safe to use Simple Green on aluminum?
Simple Green products have been successfully and safely used on aircraft, automotive, industrial and consumer aluminum items for over 20 years. However, caution and common sense must be used: Aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green or Crystal Simple Green can accelerate the corrosion process. Therefore, contact times of All-Purpose Simple Green and Crystal Simple Green with unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green/Crystal Simple Green residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation."

Personally I have an axe to grind re: Simple Green after it ate the clear coat off my F650 wheels but I really think there are other products out there WAY better at cleaning aluminum and alloys with NO risk that it doesn't make sense to use it. A little white powder on a /5 engine is one thing, but there's nothing like the feeling of finding deep water spots etched into a vintage Ducati case that you've just paid big bucks to have polished. Steve, the guy who runs "Bevel Heaven. com" ducati site suggested never spraying SG on dry alloy and I suspect that would have the same benefit as Bruce mixing it 50/50 but like I said, there are so many other products better suited.