How do you get bike chain grease out of trousers?

Apply some Dawn dish liquid directly to the stains...

Butter! It's an old kitchen remedy that really works. Just rub some butter into the grease stain with your fingers. Keep rubbing some more in as it lifts the grease. It will smear it around, and it will look horrible at first, but it really does work.

After you have done that, wash the clothing in warm water really well.

I've saved white pants with that remedy!

This sounds wierd, but I swear it works! To remove grease stains on clothes, especially those dark ones used in bolts & nuts of cars, apply margarine over the grease & rub gently. Apply more margarine if stain is still visible. Wash article as usual afterwards.

"Oil Eaters" and you buy it anywhere the sell auto accessories. I've sprayed it directly to the stain, and it come ou after laundering, or follow the directions on the bottle for laundry. It's awwesome stuff!~~

Dry cleaner might be your best choice. Over the counter products won't do and not much you can do about the chemical odor after it.