I converted my 2005 with a Lefty to 27.5 a couple of years ago. No problems. I can't use the FR setting, so if you want a slacker head angle you will have to use the offset headset bearings. I can't remember who makes them.
I have a Lefty Max 140 that was a TPC converted to the PBR with Solo Air.
My name is Chris and I ride a Prophet 650b with a Lefty.
I converted my 2005 with a Lefty to 27.5 a couple of years ago. No problems. I can't use the FR setting, so if you want a slacker head angle you will have to use the offset headset bearings. I can't remember who makes them.
I have a Lefty Max 140 that was a TPC converted to the PBR with Solo Air.