Join Date: Jan 2013
Location: Sierra Vista, Arizona
Well since this seems to be a bit of a collective build thread thus far, I hope the OP doesn't mind that I get in on the action with a similar rebuild with a slightly lower budget (Geared toward the reliability crowd more than big power crowd). I'll wait to post my specs and plans before I do a full on thread hijack though.
However, I would like to ask a couple questions right off the bat....
Concerning the Kibblewhite valves, they are obviously much easier to get a hold of compared to Ferrea valves. However, I have heard many horror stories about Kibblewhite valves.
Supposedly they are not a true 1 piece valve, but rather starts as 2 pieces which are friction welded together and machined. The Suzuki crowd seems to have been hit the worst with issues from KW valves based on my reading, but they apparently are known to break right at that friction weld, which is on the transition from straight stem to the flare outward to the head of the valve. Another thing that worries me is the stellite tip coating, how much good does it really do, and will there be any special break in procedures needed that could negatively affect the break in of the rest of the engine? (like running at a very high idle for X amount of minutes, etc.).
This really discourages me from purchasing KW valves, considering my budget, I really can't afford to have a valve break and shred my top end. However, considering they are similar in price to Ferrea valves, is it really worth the ease of obtaining KW valves to go with them vs. Ferrea? Or are the horror stories I have read about KW valves limited to a select few models and generally considered good for the 660? Anyone here have personal experience with KW valves in their 660?
My next concern is I have an 11:1 CP piston and a 102mm bored cylinder to match, but I've read this leaves the stock sleeve pretty thin around the base. For a mild build (this will not be some 60HP monster drag bike/duner), am I likely to ever have much of an issue because of this, or am I just over thinking things a bit?
My background is more in the full size four wheeling arena, trucks/buggies/etc., land of the often overbuilt, and mentality of "If it can break, it will break/if it's not on 1 tons or built 9''s, it's no good", so I tend to over think things that need not be over thought. I'm all about reliability without too much filler/bs/things I don't need involved whenever possible. I am not a newbie to mechanical things, and I am not the slightest bit intimidated by a complete rebuild of this quad engine, even though I've never messed with one before. I just don't know what's good and what sucks in the ATV aftermarket.