Hmmm, if 3 months palang ang bike mo, it can't be the bearings. Kung bearings
man hindi lang random, every time na ipe-pedal laging may aligas-gas.
But since you mentioned "lumalagutok" it can only be the chain. Malamang may konting
misalignment yung derailleur mo sa designated na speed ng cogs (e.g. pag shift mo sa
3rd speed kumagat nga sa teeth ng 3rd speed cog but hindi precise ung position ng
teeth dun sa holes ng chains), dahil dun, hirap yung chain sa designated teeth ng cog,
either gustong lumipat sa 4th or bumaba sa 2nd speed cog, so every time na gusto nyang lumipat,
dun xa lumalagutok, we can call it an "involuntary shifting", hehe. Perhaps in your case, changing
shift would do just fine pero xempre hindi naman permanently steady ung derailleur,
may spring xa and may adjustment screws, that's why gagalaw at gagalaw, at mawawala sa
alignment every now and then. You can always find some tut in youtube BUT if you wish to
do some adjustment, huwag mo na munang galawin yung front derailleur, kasi it's really tricky.
Rear derailleur is far more safer and easier to adjust. Check mo din yung front cog mo,
baka kasi "Umotso" kaya. Dapat smoothly parallel aligned yung front and rear cogs.
Need mo talagang "sipatin" sa likod/ back view kung aligned nga habang pinipedal.
check mo itong pic sa ibaba, ung misalinged, Dapat aligned yung rear cog mo sa pulley,
sa lahat ng shifts. dahil @ 2-3 mm misalignment, talagang magko-cause yan ng lagutok
(the width of the smaller hole in bicycle chain is only 3mm, kakasukat ko lang)
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