Brake booster for Demon 340

I tried the oem dual-diaphragm set-up, but wasn't happy with the boost. Since they are a bolt together deal, I took it apart to see if there was something wrong with it, or if I could mod it.The short answer is no, and no.
I switched to something oem to the later 73upDarts. Yeah its a bit bigger and mundane looking, but it works. And I wouldn't give it up. A little tweaking of the pushrod length and perfect feel. Plus if it fails, they are cheap and easy to find.