Okay here is the setup for the story. I am going to have a 680 big bore installed on my XR650R. I posted here and several other places for advice on who to use. One of the suggestions I got was from Precision Concepts. I'm going to paste my email to them on here and then their first response and then there second response. Would someone please help me figure out what they are saying and what I shoudl do? (My email to them) I have a 2001 XR650R that I would like to consider putting a 680 big bore kit in. I use it for off-road desert riding, woods tight trail, and I also have it converted to SM and use it on road only, no track. I would like to consider having someone like you install big bore kit and other parts to maximize HP while still maintaining as much reliability as possible. I have it fully uncorked, FMF header and White muffler, and Edelbrock carb. I will probably have the Edelbrock bored. Would you please let me know what you would recommend to fit my purpose and the parts and cost for you to install? I will ship the motor. Thank you, (Their 1st response) Hi Jim, I'm a bit confused, do you use this bike for offroad or SM? Diane (Their 2nd response) For offroad, we found that while the bike felt faster, it was not and was more cumbersome to turn with the big bore in. Honestly can someone tell me if this is serious and I just dont' get it or what?