Piston rings failed to seat


I have come to the conclusion that the piston rings has failed to seat on my 1441 bigbore hayabusa. The compression is only 200psi with stock cams and 12.88:1 CR. Spark plug threads are oily and when I applyed 14psi compressed air through spark plug hole, there is a lot of air exiting the crankcase breather hose. I did the compressed air test to both this 1441cc motor and my stock spare busa motor. The 1441 motor filled a 1 liter plastic bag with air completely in 3 minutes via the crankcase vent hose. The stock motor failed to the bag with air, stopped the stopwatch after 10 minutes.
The motor has done 2500kms after rebuild with bigbore and new pistons. I used 10/30W mineral oil for break-in, but did not realize that is was important to apply load and rpm during break-in. I drove it very gentle during the first tank of gas. Basically I the worst thing :-(
Now I will have to order new piston rings and head gasket. Do the cyilnders need a re-hone??

14psi test.jpg

did you gap your rings ? Get them installed in correct direction ?
The cylinder hone actually look a little rough (coarse) to me but that could be the photo.
Did you oil the rings when you put it together?
This is what I use and the rings seat pretty quick.
Usually though I warm it up after overhaul, check for leaks then off to the dyno.
We all have learned lessons

I did check gap i bores before installing rings, with "n" stamp facing the top. I used 10W30 mineral oil to oil the bores and pistons before installing.
Here are some pictures taken today, I desided to take the motor apart..
I dont know how to "read" the rings and what to look for. But the top ring edge is smooth and feels round-ish. 2nd ring edge feels sharp when you drag a finger across.






Can you have a machine shop hone the cylinders?
If you hone them by hand you can never be consistent with the speed, stroke length, and angle, and essentially put 'waves' in the cylinder walls.
The bores look ok in the pictures, but under the circumstances, I would have a shop hone them on a machine.
With proper ring gap, And gap spacing.
Were your ring gaps spaced evenly apart?
The ring gaps Cannot be in alignment with each other.
And yes, a hard break-in is what they need, up throughout the rpms and engine braking down, repeat, constantly varying the rpms.
Yes, we have a machine shop nearby, I can ask them if the have the tools for honing nikasil cylinders.
I spaced the gap in the rings 120deg apart like stated in the workshop manual.
I will place on order for new JE rings and headgasket and this time go for the hard break-in
Just for reference, I'm using Wossner pistons and my top ring gap is .45mm and I don't have those issues. So no you shouldn't be getting that much blowby. Did you check your valve seals? Replace? How about the valve guides? Potential head issue?

Also, don't hone on the nikasil. If the nikasil is good leave it be. Get someone that knows how to work with it if needed. Unless you're seeing gouges in the cylinder walls, I don't think the cylinders are the issue. Tough to see from photos but they look okay. The one photo in the sun looks like cylinder 1 and 2 have a drag line on the left of the cylinder a quarter of the way down, but that could also be a reflection.
Judging by the photos cylinders fine. Did you do a couple idle heat cycle before you rode it? I think your supposed to do like 5 of those and then go ride it. I did that when I rebuilt my bigbore motor. I didn’t have any issues doing it that way.
When I had my cylinder head streamlined this winter, there was installed new intake valves. All the valves where seated with paste and checked for leaks. I replaces the valve stem seals with new ones after the head work was done. I checked the valves for leaks before I took motor apart yesterday, they seal just fine.
When I first installed the pistons I did gap the ring to JEs specs for "street motor". I didnt realize at that time the gen2 stock ring had smaller gap tolerances, but mabye the JE rings expand more and seals the same?!
Due to new camshaft installed on first startup I was focused on letting the bike run for 30+minutes above 3000rpm without load, specified by the cam manufactorer. Then followed by some runs with partial load.
It seems JE recomends the hard break-in:

"According to JE’s Senior Technical Account Manager Alan Stevenson, “You don’t want to break-in an engine at idle. You want to keep the rpm above 1,500 and vary the speed continuously for about the first 20 minutes.” After bringing the engine up to normalized coolant and oil temperature, put the engine under load. The cylinder pressure from 50 to 75 percent and eventually to 100 percent load will place additional pressure on the back side of the rings which will quickly establish the proper wear pattern for seating. With today’s rings, especially moly-faced versions, this can be achieved in a very short period of time and certainly within 20 to 30 miles of street driving. In WOT dyno testing, likely the rings are seated by the end of the first few runs."
I am having a hard time finding oil specific for break-in oil here local. Do you guys think it will work using "classic car oil" SAE30 mineral oil with low detergents and no zinc? I am thinking that mabye conventional mineral car oil will have to much friction reducing?!
I am having a hard time finding oil specific for break-in oil here local.

Porsches are factory filled with the same Mobil 1 oil that we can buy, and Porsche even requires a fairly long break-in.

In that light I suggest that you follow @ColdBusa's advice and fill the engine with the high quality motorcycle oil that you use to maintain your bikes. Never again be distracted by the myth of "break-in oil."

Hopefully you identified the very specific reasons why the build did not work right, but those reasons do not include the oil selection. Oil cannot and will not prevent an engine from seating.