Godofchaos

So i have a really annoying problem. Imagine riding your bike and everytime you pedal you hear an old rocking chair. Thats what i hear 24/7 and i can't figure out what it is. Ive greased both rims and checked them for any damages and i ended up with nothing. Its not the pedals because ive tried multiple different pedals. Everything is tight, no loose bolts or anything. The back rim in aligned near perfectly. It only does it when i pedal (or spin it backwards) but it needs to have pressure on it, like someones on it.
I suppose a little more detail would help. Its a 24in mcs (before you say scrap it, i plan on using the parts to build a 24 in diamondback), 3 peice crank with a European bottom bracket (cant be changed to anything else). I dont know what else you need to know but like ANY suggestions at this point would be amazing.

-ps the chain ring is NOT bent. It came off an old bike and it worked just fine and i made sure there wasnt a bend in it

cbrstar

Creaks can be a number of things so a few things to check.

1) Loose hubs or worn out bearings
2) Loose spokes
3) Loose crank arms or worn out crank bearings
4) Loose headset or stem

When you pedal you are applying torque which is why something loose is creaking. BTW MCS is an awesome bike especially if it's an older one.

tds101 

Bottom bracket is shot,...needs to be replaced

Bikerider007

The most common creaking experiences I've had with cranks on BMX bikes is aluminum crank works loose and will strip if not tightened. Chromo cranks will get cracks that creak.

Typically those types are from jumping, 180/360 type stuff where your weight drops while pedals are horizontal.

This is a fairlly recent one for me. Doing some BMX type stuff on a PK Ripper fixed.




This is

EdwinHeadwind

The cheapest and least invasive first step should be to remove the pedals (left side is reverse-threaded), grease their threads and re-install. But I would bet dollars to donuts that it's the BB. The good news is that cartridge Euro bottom brackets are inexpensive and super easy to replace. A new BB, some fresh grease and proper tightening of the cups (and the crankarms) ought to take care of it. My advice would be to let your local bike shop pull the old one to make sure the replacement is the same shell width and spindle length.