Piston problems - flywheel/con rod clearance
long story short, i cracked the rear piston up both sides of the skirt, right behind the wrist pin on the intake side. gouged the cylinder pretty good (going to have to bore over again)
I'm going with 10.5:1 this time around (a bit better suited to the W8, and will support a W9 if for some reason I decide the bike needs a 5th cam lol)
Im not afraid to spend $$$ on quality....honestly I prefer it (its always been my luck that its "pay me now or pay me later"...either way it's gonna happen.
and preference to brands? the biggest thing I notice about the wiseco's is how long the skirt is (and it was a SOLID impact...about a 1/8-3/16" dent)
These are all .010" over...i'm already bored .005" over...and my indy seems to think I can get away with the .010" over (ill know for sure tomorrow once he gets em in torque plates and measures them). good thing theres no big price difference.
CP - forged 10.5:1, M5009
JE - forged, PN 134094
KB - forged, with offset wrist pins (not really sure on the upside to these...but their forged pistons all come with offset pins)
KB - hypercast (same as OEM unless i'm mistaken), no offset wrist pin
dunno about a lot of other offerings. I'm really hesitant to even give wiseco another chance. I'm waiting on a call back from them, see if they have any insight as to why these hit.
i guess the upside is I know the clacking I was hearing that I always attributed to those "noisy woods cams" simply isnt the case.
destroyed wiseco's -- for reference

Don't use the Keith Blacks, they are hyperteurectic or something fancy and not like OEM...go with forged. I recommend using stock pistons and planing the head to get higher compression as its easier to reverse by using different gaskets.
John
I guess you pulled up and down on the rod already, any slack?
Unless there was an obvious app, defect or install issue,
the piston's just a casualty.
That jug has to have some major taper at the bottom now, don't see .005 (.0025 actually) cleaning that up.
Need to get all the metal out the engine crevices, oil hoses, and tank anyway.
Hate this happened.
I'm fairly sure the piston is the defect. Bottom end is still tight, and no metal shavings were found (the skirt is cracked And dented... No pieces missing). The skirt on the Wiseco is a lot longer than stock pistons, and they were absolutely installed in the right orientation (that got checked 3 or 4 times before the jugs went on. My only guess now is that wiseco put the wrong pistons in the box, or 2 fronts vs 1f and 1r. The skirts are identical heights from the wrist pin on both pistons.
The scoring really wasn't bad, enough to feel, but no major gouges. Hopefully I hear back today as to how much they need to be bored so I can order pistons ASAP. Really wanna limit downtime at this point
Last edited by Jasper86; May 31, 2013 at 08:50 AM.
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The scoring really wasn't bad, enough to feel, but no major gouges. Hopefully I hear back today as to how much they need to be bored so I can order pistons ASAP. Really wanna limit downtime at this point
The 3 guys I talked to already, (who are all builders) said the bottom end should be fine as long as the rod bearings are good. Either way I don't have the cash to redo the bottom end too. Odds are this hit the first time it was turned over and that's why it's been clacking since day one. I won't know more until I get home from work and can dig in a little deeper
Don't forget, it's been running for 2500 miles or so like this. I only tore down because I recently bought a leak down tester and realized the rear cylinder was low.









