Hey everyone,
I've had an 88.0mm Wiseco piston in this bike for ages and it finally checked out when the intake boot cracked and breached, allowing atmospheric air into the combustion cycle (poor maintenance on my part). They have 1 sleeve readily available in stock at my machine shop, they also have 1 piston available as well- meaning no waiting on parts which is weeks of added time otherwise. Then I found Wossner's big bore pistons 90mm & 91mm available. What I didn't initially realize was that the head will likely need modification, as well as the power valve and who knows what else. I initially thought i'd be saving money by not having to re-sleeve but it doesn't appear that way in the slightest (I'm still waiting on the actual quote as they're swamped right now). Does anyone have experience or input on this topic? I'd be willing to spend a little more now to make this big accept the bigger pistons but not if it means a bunch of revert work when the time does come to re-sleeve and go back to OEM bore and specs. I'm ultimately after durability and longevity. Sure the extra CC's and power is enticing, but not if it increases the probability of issues. If the mods are done to accept the 90/91mm pistons will this work then have to be reverted when I re-sleeve & go back to OEM bore or will this work be compatible with all piston sizes? (86-91mm). What have you guys experienced and what would you recommend? I do know i'm going to be sending the head out for the decompression mod by Larry Wiechman. Any thoughts on the matter would be appreciated! Thanks. Chris-