chain clearance

I just bought a 1979 XS650 and got it home yesterday, I saw it on facebook and fell in love with the style, the simplicity, and knowledge of the power and reliability has me hooked on taking care of this pretty much entirely stock 650 from over 4 decades ago. One thing I noticed while riding it...

I am perplexed by this ongoing safety issue. I noticed that the chain is tight then loose then tight and so on as the wheel spins. My first thought is that something is bent. I took it all apart and I have found nothing is bent. I used a laser level to see into the drive sprocket, I have checked...

hi folks, hope you all had a good holiday weekend. I am sooooo close to being ready to tear down for paint. I have a sissy bar bent "loop" coming with tail light mount. Once I sort that, and finalize that's how I want it, this thing is ready tear down for paint, finishing etc. Not sure why...