I know the Kramer 650g is not technically a “bass”, but I own several of the bass variety. I found this forum looking for a fix for a 1976-77 Kramer 650g Aluminum neck. I didn’t notice it when I purchased it, but after examining the neck, it has a significant up-bow with way too much relief. I found a thread that suggested putting the neck on two chairs and jumping on the middle. I may try this as a last resort. I was wondering if anyone had found a solution to these types of issues. I appreciate you all! Thank you for letting me join the forum. I am happy to be here.