An update on things done last month:
Dismissed exhaust header temp difference after polishing them both: IR thermometer was lying due to different reflectivity.
Got digital oscilloscope-multimeter combo gadget.
Scoped coil primaries, look fine. Used this guide as reference wasted spark ignition...
Quick update, found this thread https://www.600cc.org/threads/2011-xj6n-cylinder-1-4-misfire.34266/
TL;DR on hot engine ECU stops driving injectors 1&4, causing misfires and symptoms similar to mine.
I've tried bridging injectors 1 & 4 from 2 & 3, both power and switching contacts, as...
I'll try dumping media openly then. I think after first 4 they stop embedding and just show up as a link.
Injector test, since then I swapped to old ones that came with bike, and tested them too. They work just as fine.
Spark plug test.
Interesting that I stopped riding bike since Monday...
I spoilered vids to avoid spamming one post with 3 videos, but only links to imgur show up that way.
Picrelated are spark plugs in June, before I changed them and before other manipulations with bike. They looked even and fine, nice white porcelain isolator down the middle.
Valve job was far...
I did that today through diag menu. All injectors spray fuel properly. I don't know how well it can be seen from the video though.
While I was in there, I did spark plug test too, all spark plugs work but there is a BUT
The BUT is that Cyl1 & 4 spark plugs are all crapped up, barely can see...
So I have tested terminals that feed into coils from harness with multimeter:
Ignition ON
Black probe to BAT -
Red probe to Orange-Black terminal Left Coil and Red-Black Right coil terminal
This returned 12V properly. Then I connected the coils and put red multimiter probe on a tiny exposed...
So I bought a lazer temp gun and took it to exhaust header temps. Roughly 5cm down from engine block, collected about 20-30 datapoints for each cylinder, below are averages.
Outer cylinder 1 & 4 headers are ~40% cooler than inner cylinder 2 & 3 headers. And difference persists when revving bike...
I did the throttle sync. Not the final result on the pic as a ended up moving it a bit closer to 20 across all cylinders, but looking at the manual now it's 238mmHG so maybe I should up it a bit. I knew not to mess with center screw but I didn't find it anyway on my bike. Syncing was done at...
Old ones looked fine (picrelated), I recently replaced them with iridium ones.
200 200 200 195 Psi.
I'll look into it. If I understand procedure correctly you TDC the cylinder, pump air through spark plug hole and see how much pressure escapes, correct?
Would it show on intake vacuum lines...
TPS on my bike only goes up to 90 in diag menu. But smoothly so, without any dead spots or drops. More generally, I'm trying to nail down reason for violent vibrations after ~4K RPM. Just noticed the TPS thing in the process.
2D1-85885-01-00 & 2D1-85885-00-00 TPS are used across many yamaha bikes, including some years of FZ6, R7, R1 etc. So it should still apply. But thanks for reference.
I've 2011 FZ6R (XJ6 Diversion) and TPS goes from 16 to 90 in diag menu. Is this normal? It's smooth without any faults between min and max. Just worried that MAX is too low. The bike does suffer from vibration and seemingly loss of top power.