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[BarrySEUltra-103]

Ok guys just looking for some opinions from maybee some builders on here , heres the story

I have a 2006 se 103 ultra i built a 107 with dome pistons  from zippers did the whole 9 yards pump plate cams ect except the crank (stock) and after 700 miles it developed a massive piston knock the skirt was smacking the bottom of the cylinder on up stroke. So i had the stock crank rebuilt trued and welded , rebuilt the motor again now at 1400 miles same problem theres a sticky spot in the crank again. So my question here is am i missing something? Is something causing this orr was it just a bad crank rebuild , the first crank had 60k miles on it so i chalked it up as wear . I was using a thunder max to tune no sign of excessive detonation on plugs or piston tops 🤷‍♂️🤷‍♂️🤷‍♂️

[BarrySEUltra-103]

More pictures

[HD Street Performance]

What did zippers say? What brand are the pistons? How long did it take to fail. What was your breakin procedure?

[BarrySEUltra-103]

What did zippers say? What brand are the pistons? How long did it take to fail. What was your breakin procedure?

Carillo (cp) pistons from zippers , havnt had much luck talking to zippers in the past so i have not tried to talk to them since the failure . Break in i do a sequence of heat cycles then a few short rides letting it cool , changed the oil at 25 miles then 100 miles then 500 . Didnt do any highway cruising until it had 300 miles of in town riding up and down in the rpms . I dont think this is a break in failure it had almost 1500 miles on it . Bot failures happened on 5th gear above 100mph

[BarrySEUltra-103]

Sent a email to zipper see if i get a reply

[HD Street Performance]

What about the tune? Was this done by dyno with AFR monitoring.
You say crank is stock. Did you check runout and for stiff rods?

[BarrySEUltra-103]

No dyno ,thundermax with auto tune adjustments and i made some timing adjustments to take out knock . I had sticky rods the first failure had the crank rebuild trued and welded. Thinking that was the culprit but now i have a second failure in the exact same way and timing. Both failures were in 5th gear 100+mph under load 4500 rpmish zippers seems to think its a oiling issue and want me to check the camplate its a new s&s plate and pump

[HD Street Performance]

What was your cleaning routine before build #1 and #2. Was the oil pan replaced? All lines and passages cleaned and bottom end disassembled and reassembled?
And the wide bands.. are they right out of the heads in the pipe? Thundermax, as you know, uses throttle position and RPM to direct fuel delivery, what was the target AFR at your 40% ish throttle and 4500 rpm?