Welcome. What year is your Nighthawk? I'm assuming the Nighthawk engine would be comparable to the Rebel engine of the same year(s). So if you have an 1985-95 Nighthawk, pistons and rings from a first generation Rebel engine (1985-87) should fit, and ditto for the second genertion Rebels, 1996-2016 and 1996 & up Nighthawk. All years may be interchangeable, but I'm not 100% sure of that. Someone else may have the answer.
Thanks for the reply! I've read a few of your posts already in some other threads while trying to figure this out haha.
It's a 2007, so second gen. It may have added a little unnecessary confusion to point out that it's a Nighthawk but I figured specificity is good.
I know the parts would be the same across CB250 Nighthawk to CMX250 Rebel. And to clarify for other readers, I'm hoping to transfer from a first gen Rebel to a second gen Nighthawk.
It seems like they would fit, right? I know it will be tough to find a 100% on this but maybe someone on here has some of each lying around and some spare time to put a micrometer to it. The parts for the original rebel are significantly cheaper, especially used.
Another thought I have is just transposing sleeves. I've never really done a rebuild before, so I am not sure if this is a stupid question, but could I just get a decent used jug from an old rebel and knock the sleeves out, then put them in my bike, hone them, throw the old rebel pistons in and be good to go?