Waqar Bukhari Yes bro AX-5 is relatively better than the other local available. LM is the best affordable oil you can procure,there is absolutely no match.I have tested all brands AHL,Caltex,Kixx,Ax-5 but when i poured in LM i experienced notable change in engine noise as well as transmission.
Falat1ty brother 20w40 is an all rounder for pakistani conditions.The grades are primaly influenced by engine make and model rather than climate(oil clearance and stuff,though the latter is also considered).@20w40/50 behave exactly same on cold start,and can be easily substituted without any noticeable change.Thin oils are generally not recommended for our local bikes and the conditions are not that severe to use 10w/5w viscous oils.I am using LM in both winters and summers and there is no issue at all.
Amjad sir oil turning black is a good phenomena.Instead of turning the deposits into sludge the oil displaces those deposits and keeps them within itself so as to prevent formation of sludge.ANd when you drain the oil those deposits drain aswell.A clean oil which has clocked more than 1500 kms and there is no noticeable difference in color is a sign of great concers as the oil is unable to clear deposits from the engine. That's how oil does its job
Lm drain is dependent on vehicle make/manufacturer conditions for e.g for GS its 2500,for CD 100 its 2000 (but i drain it at 1.5k +/- 100 Kms for my own satisfaction.The oil can stretch till 2k without causing any harm