I have a 2008 750 ( new to me a month ago) that was running and idling poorly. It was through this forum that I came to the conclusion i should check the valves. Well it turned out that the valves were exceptionally tight (cold engine) and once I set them properly it starts, idles and revs up nicely....but....I can really hear valve noise now. I have triple checked the clearances (cold engine) according to the manual (.5 front .8 rear) and they are always spot on. I am wondering if I have to wait a bit for it to set in or should I forego any further operations until I replace them as mentioned above? Will the noise subside once they settle in? The snow is getting deep here now so changing out the valves would be a good winter project for me, just don't want to do any unnecessary work if I can help it. It's not my intent to hijack this thread, but it think any reply would be relevant to the OP's concerns.