I have 2008 FXDL with Black engine cyclinder fins with the outer edges unpainted. The front leading fins are beginning to turn a spotty black. Does anyone know how to restore?

Thanks

 

The S-100 engine brightner from the HD dealer works great. Just spray it on and the engine looks new again.
J.B.

 

Spray with your choice of cleaners. S100, simple green, shout, whatever. Wet the bike first. Spray with cleaner and let sit for a few minutes. Use a paint brush to get the cleaner all over the fins and in between. Let sit a few more minutes and rinse. Then hit with pig spit or s100 engine brightener.

 

How do I get the pig to spit on it? Never mind here she comes I'll just ask her!

 

+1 on this. S-100 engine bright is a great product after you clean the fins with simple green.

 

I think he is refering to the actual machined edges of the fins, not the black part.

 

Yes! I have the same problem on the same 2008 FXDL!!
The problem is the thin silver cooling fin surface(not the black surface) getting kind of oxidation build up, its hard to clean, I try use a soft send paper to polished a but, its still there!
so is that S-100 can really work that out?
help please!

 

I would like to know also what else it out there. For me so far pigspit and a wipe down works!

 

It is some kind of oxidation on the machined out part of the cooling fins. S-100 and pg spit does not work. I tried some fine sand paper with little luck.

 

Once the bright machined edges of the cylinders get dirty and oxidized getting them to look like new is not possible in my opinion, I tried different cleaning compounds and abrasives. I bought my bike used so I had no control of how clean it was kept before me but if I was to buy a new bike I'd be using the S-100 products to maintain the engine.

Good luck,
Mike