You are right about ustaad log those who claim there hand is feeler gauge
but here honda mechanic in my city has really surprised me and i have checked
bike tappets after tuning the settings come out accurate just giving you example
of last tuning he never uses feeler gauge i personally requested him to set the
intake valve little tight & exaust valve little loose (means to factory settings)
after tuning i came back home and checked the settings with feeler gauge
exaust valve was exactly perfect 0.05mm and feeler gauge was also going in intake valve
but just with some drag little force
and this is not the first time from last three tuning i have been monitoring his settings
First tuning he set the valves Intake just little tight & exaust exact 0.05mm
2nd tuning he set the valves Intake exact 0.05mm & exaust little tight
3rd tuning he set the valves Intake exact 0.05mm & Exaust little too tight (Gauge was not going)
4th last recent whose experience i shared above this i personally requested him to
set the valves as Intake if little bit tight ok but let the Exaust valve loose as compare to Intake
as this is recommended and he acknowledged that said aise h hoti hai correct settings
i told him i have been monitoring your valve settings from last 4 tunings and told him to
set the valves like you did in first tuning and he done the exact same settings which i told him
Though i personally have experimented setting tappets of bike and i personally too used to feel
& still feel its very very hard to set the valves to factory settings as 0.05mm without using feeler gauge
as very very little movement of tappets adjuster bolt ruins settings but i was amazed when started
monitoring honda mechanics work here in my city the years & years of experience has really given them
idea about valves position they can judge the clearance with hand by moving rocker arm or valve
he is very senior mechanic and has 30+ years of experience i have been going to him from 2012
but from last 8 months i am very satisfied with his work some time he does very foolish mistakes
like one day he had left my bikes carburetor bolts untighten and in the past i was not really satisfied with his work
now its been excellent experience with him and i really enjoy my bikes ride