Barfbucket
Finally riding a big boys bike
Nothing will get a good stuck aluminum post to steel frame loose, except sawing it out. You will destroy the frame and it will still be there if you use force, or even heat. A dielectric reaction caused by small amounts of static electricity and water welds the two together. The only way is to carefully saw it out. I have used a rod inside a sawed off post but then the seat post clamp won’t fit. I had to do some welding. Ample grease on the post will keep this from happening. Saw it out.