Cleaning old engines up
 

so i know many of you guys have been riding longer than i have been alive and thats alot of motorcycle maintenance as a collective whole, i have been rebuilding my old KZ650 SR since i got the SH and on a college students budget its slow going but ALMOST done. However i spent my entire spring break in the garage, dremeling and polishing the 30+ year old aluminum with only mild success.. very sad, it looks BETTER but not great like i would like it to, i have used old fashioned rubbing compound, heavy duty rubbing compound, mothers aluminum polish and a slight wet sand on the bad parts.... ANY suggestions on how to make these old parts shine??? there is a picture of the valve cover gasket... sorry terrible light but the right side is done and is still kind of dull...

LET ME KNOW!

If you really want it to it bright you have to take off the entire oxidation layer and get it perfectly smooth this means starting with around 320 grit wet sanding and working your way up (400, 800, 1000, and I do 2000 on some stuff) then hitting it with aluminum polish, I use 2 polishes one is master something that is fairly abrasive then use mothers billet. But don't do it unless you never want to ride it. Once it's polished it will just get scratched and dirty not to mention it will just re oxidize, there is no way to prevent it, I repeat none, no waxes powders, claercoats or resins will keep it un oxidized forever. If you want it to look trick hit it with some VHT it comes in lots of colors and the wrinkle is pretty cool.

I was afflicted with restorations on BMW airheads in the 70's and 80's, woe was me until the fevers passed.

Anyway, for engine/transmission/differential cases I bartered for time in a blast cabinet and covered the cost of the media. Micro shot gave me the best texture result, but uncoated alloys oxidize again.

For a KZ 650 I'd think the point of the exercise is therapy rather than striving for a 10 point result to trailer to an auction or show somewhere. I wouldn't think that there's much collector demand there.

Just my opinion, but a well used, functional, nicely maintained motorcycle is charming with warts and all. I know of a CBX that's all original except that the engine has been resealed and all the rubber thingies have been replaced along with the seat cover. What a charmer when he rides out to bike night on it.

This is what I do if I intend to paint:

1. Sand blast using glass beads
1a. sand / wire wheel gross imperfections
1b. repeat #1.
2. Solvent to clean off the residue
3. Use textured paint - looks great, hides imperfections or powdercoat

If I want to polish / clearcoat:

1. Sand blast using glass beads
1a. sand / wire wheel gross imperfections
1b. repeat #1.
2. Solvent to clean off the residue
3. Wire wheel shine
4. sand with progressively finer paper
5. polish with polishing cream
6. repeat #2
7. clear coat - I lke disc brake or mag wheel paint - a bit tougher, for engine or high temp parts, use high temp clear coat

Anyway - a sandblaster is the way to go to really clean a part. Tractor Supply sells them.

JB

sorry for bumping a old thread but will a sandblaster with glass media take the powdercoat off the wheels as i want to polish them

I am no expert, but I would start with a less aggressive media and work my way up till I found something that did the job so that I don't accidentally blast into the metal. That said I don't know how aggressive glass is supposed to be either.. lol

Well thank you for bringing that to my attention, cuz i dont know ither

I'm not sure blasting through to raw metal is the goal or required for clean surface new color/coat. Rough it up, get it clean, put on the new stuff.

this is my intentions!!

use this stuff, it will remove powder coating and paint... but is easier on metal:

http://www.tractorsupply.com/tools/s...e-3987722#null

http://www.tractorsupply.com/wcsstor...50/3987722.jpg

Once cleaned up, I heard THESE products work very well. Do some research on the allowable temperature though.

we have been doing some soda blasting at the shop. I guess if it were parts that could be shipped, we could do some blasting.

built a booth with ventilator in my spare bedroom of my apartment time to do some blastin