galvanic corrosion - dissolving and separating dissimilar metals

Hey guys, VF1000R. #2 will be on the operating table next. the one major pain in the ass on #1 bike was removing the aluminum header retaining collars from the front 2 cylinders, they were bound hard by galvanic corrosion, in the end I had to cut off the aluminum collars (the collector box was shot anyway).

Bike #2 has a good collector so Id like to be able to dissolve the galvanic corrosion.

Penerating oils and heat do nothing for this.

any ideas ?

 

Penetrating oil and heat has been my method. And prying and banging and swearing and drinking. Didn't even want to open that can of worms on the one I'm working on this go-round. I need to make sure everything is cool and get some miles before I go there. Probably should have tackled it when I had the swingarm off tho.

 

The rear ones on project 1 were no problem, not even a bit stuck, just the front ones. some of the parts bikes I got had evidence of similar issue (Fronts only). I used penetrant and heat and prying for 4 weeks on bike #1 and got nowhere. I was going to end up bending or snapping off an exhaust stud do I opted to cut the collars off given the collector had other issues.

Im hoping to find something I can squirt in there to dissolve the corrosion and leave the aluminum alone. (may be hard to find though)