what kind of power are you picking up by going to 10:1 or 11:1? High compression usually picks up some snap down low too.
I was told you'll get more bottom end snap with the 11:1, but as far as power #'s, don't quote me on this, but I was reading some threads where people were arguing over compression ratios, and someone spit out that it's roughly a 5hp jump per every point of compression. (Ie. 10:1 - 11:1). I'm not sure if that's accurate or not, if so, that's a little over a 10% increase. Someone that knows more about this can chime in.
My rational behind doing the standard bore HC Piston over the 734 was for a couple reasons... ( I initially wanted to do the 734 BBK ).
http://www.grizzlycentral.com/forum/showthread.php?t=92561
1. I figured I'd start low and if the HC 11:1 my the other clutch mods I'm doing with it didn't give me what I needed, I can always step up to the 734 kit.
2. I didn't want to mix gas. They make 12:1 + but I don't have access to good fuel here.
3. After talking to some of the really big bore guys, once you start crossing the line of the 734 kits, the reliability goes out the window and there's a lot of down time and things get pretty expensive. Head work is required and other things far beyond my skill set and pocket book.
The 734, is a good kit, and I probably wouldn't do anything bigger than that. If I needed more than that, it would probably be time to buy a bigger bike. Overheating can become a big issue, especially on the bigger bores and well as wet clutches getting destroyed.
My plan with this 11:1 was to pair it with a more aggressive cam to help offset what i would have gained with a BBK. Problem is, no one that I've found makes a drop in Cam for 2014's-2015's (Hot Cams or Web Cams). Web Cam will custom make one, but it's 278 bucks and 3 weeks of down time. Eric at EHS, I was told, might make them now for those years, but I haven't been able to get a hold of him yet to verify that.
Anyways this is my starting point. I may join the 734 club, may not. If I can whip my heavy 30" paddle tires around in the deep snow to my liking with this setup, then that's where I'll probably stay. Good luck with your build though. It's fun to get new stuff in the mail haha
