I had cycling crash and had liver laceration grade 2, how long and time should i recover (rest) and start cycling again?

Good question: No one really knows for sure how long liver lacerations take to heal, but it depends on extent of damage, associated organ injury, location of injury, etc. I would say 3 months to resume, if you are doing competitive cycling. If you are just riding with low risk of another crash, you can probably resume as soon as pain resolves. Ask your trauma surgeon for specific recommendations in your case