Injector - lean mixture long injection time

Hi all, i have a question regarding injector testing with oscilloscope. This is for a maxi-scooter not a car, it's a Yamaha Majesty 400cc (one cylinder), with very lean condition. I have adjusted valve clearance (now in spec). The only downside befor valve adjustment compression pressure was 9bar, now it's 10 bar and should be around 12-14 bar, so probably piston rings worn out. Previous spark plug didn't had any oil sign and looked with a camera inside the cylinder all good.

I find unusual that hump on the mechanical movement. It's the first time i see it so pronounced. Usually on all bikes i've tested it's a bit smaller. This looks exagerated. 
I've tested with Pico 6 Automotive also and the same.
Also injection time it's a bit too much from my experience near 4ms (usually 2.5 even on a one cylinder engine)
Do you any see a problem with the injector?

*injector was cleaned ultrasonically and tested with bench machine (it wasn't dirty, before and after clean the same atomisation and fuel qty sprayed)
*coil primary/secondary all good, also with CKP sensor spark and injection timing ok, no issues, even on constant throttle or just blipping.
*scooter was dropping idle when comming to stop and engine shut down if not blipping the throttle (cold and warm)

Wow, that's a cool waveform! I don't have any insight for you, but I've never seen such a pronounced pintle bump working on cars.

yeah me too, but another pro in bikes said it's ok, depending much on the design of the injector, on others can barely see the pintle.
for me personally it's not ok until i have 3-4 the same model and check for all of them...