Used cams

[Heretic]

this is a crap shoot. using mics on a cam only tells you if lobe height is correct. it tells you nothing about ramp angle and radius.

However, it will tell if the lobes are worn..

If they look good, and you decide to use them, new lifters are mandatory. use very fine sand paper (1500-2000 grit) or emery cloth to clean the surface area of the cam lobes. the cam will not have the drag of the old flat tappet car cams, but imperfections in the surface will destroy lifters

Remember that the new roller cams have a hardened surface for the rollers and they do not recommend sanding it anymore.

They also do not recommend utilizing previously used cams at all....in fact they recommend against that.
quality steel cams should bear no adverse effects from removing surface imperfections with very fine sand paper. if the hard facing is so shallow that you can sand through it, then those cams belong in a landfill somewhere.........you should be able to do nothing more than put a shine on the surface, and remove surface imperfections, if the cam was surfaced correctly

just FYI....I used to be a machinist......I might have even cut a cam or two myself

[junior]

i can see the need for practicality in the original question- especially in these rough times. roller tappet cams are square across the lobe surface, where flat tappet cams are crowned (this causes the lifter to rotate as it goes up the lifter bore so you do not wear them in one spot only). although i've never "sanded" a cam before, i agree that a better quality cam should be surface hardened enough where a light polishing with a microfine paper wouldn't hurt. if i were to try it i'd use a wet paper on a piece of glass or plexi, then rotate the cam against it rather than trying to polish by hand per se. in the event that the first pass showed wear grooves or pitting, i'd toss them immediately.

that, imho, is the risk you take using used parts.

j

[arthureld]

The reason I was told to sand cams is so it will wear in better. Especially the shiny spots where the surface has already worn in to the old parts. I'm just talking about making it slightly dull not scratching the hell out of it. My Ducati had chrome plated cams so I don't know if you should sand something like that.
Most of the time it probably makes no difference.
I used lots of used parts on VWs, but I could buy used VW motors for $100.
A Harley motor must be worth close to $5000 and that's why I would not put used cams in one.