Rear cylinder piston carbon buildup? worse?
i've been chasing a weird metallic tapping sound that occurs from 2800-3000rpm that sounded like rocker arms flapping or a lifter not pumping up. only happens while driving and while moving and only through that rpm range. i couldn't replicate it on the bike lift.
so far i totally went through primary, compensator, clutch. replaced lifters, readjusted pushrods, serviced and check rocker boxes and arms, pulled cam plate and checked cams, bearings, and lifters.
finally was able to put a borescope down the cylinders and found the rear piston looking like this. anyone have any ideas if this is normal??? the front cylinder had carbon but it wasn't broken apart and it looked like a normal piston that had been running.
think this has something to do with the noise i've been chasing?
2012 FLTRX - stage 1.5 headwork, dragos 580 cams, 10.25 comp, FM stage 1 intake, dragula 2, TTS, 13" windvest, 14" evil apes, JRI 12" shocks, progressive monotubes, hertz and alpine, hawg wired amp, custom LED gauges, custom dynamics LED signals, lots o' powder coat
San Diego, CA