what can you substitute for grease for fixie bikes?

I use car lithium grease. Autozone or walmart

Bike Grease Alternative

I'm assuming you are referring to the bearings. You wouldn't want to use much other than the proper bike bearing grease. Grease is made for specific uses and is relative to rpm, generated heat, etc.. As someone else correctly answered, you may need the thick bearing grease to hold the bearings in place. You should take the time to get the grease you need.

On the rest of the bike, you should use an appropriate bike lube, either wet or dry. Never use WD40 on a bike; it is not primarily a lube. The WD in WD40 means "water displacement". It feels slippery, and it does contain a thin oil, but it will not lubricate bike parts.

There are probably some other products that may work ok but I've found a pretty good grease to use on my bike. Its called bike grease. Do you want to sacrifice your bearings to save a couple bucks?

You can buy grease from the auto store or Walmart. I bought a can of MultiTech in the auto section at Walmart for $3.77 it's more conveniont then the tube grease used in grease guns. Walmart also sells bicycle chain oil now if that is what you need.

depends

what part of the bike do you want to use it on?

you can use other stuff

anything slippery

it just may not last long

oil won;t last long where you are supposed to be using grease

if you don;t use grease in the wheel bearings you may not be able to assemble them - the bearings may depend on the grease to temporarily hold them in position during assembly

why not just get the right stuff to begin with>?

wle.

wd-40