Thanks for waiting. I find it interesting that they believe that they are attempting to obtain a lien when they no longer have possession of the bike. In California, a lien sale can only occur if the lien holder has actual possession of the bike. In fact, the statutes states that the lien is dependent upon possession. Thus, if they don't have possession, they don't have a lien.
That being said, this means you are not in any sort of imminent danger
of losing your vehicle to a lien sale. Something about this situation makes me think that the two company is confused about the motorcycle they are trying to get a lien on. I say that because it is pointless to send you the Notice of Lien Sale form you mentioned above if they don't actually have possession of the bike.
I've looked up the Notice of Lien Sale form and see the spot you fill out to provide notice of your opposition. Go ahead and provide the information requested and sign it. This will show your opposition.
I would send a letter to the tow company, explaining that California Civil Code
Section 3068.1 states that there is no lien on your vehicle because you have possession of the vehicle and removed it from the lot after they towed it there on the same day. State that you dispute the amount charged by them, as you have already paid them for their services for towing, and they informed you that there would be no charge for storage of the bike, as it was picked up on the same day and they did not charge you for storage when you picked it up. Tell them that they have no right to file a lien and that you owe them no money for the prices they incurred in doing that. Along with the letter, send copies of the receipt.
In the long run, they may have a valid claim for a storage fee of less than 8 hours, although $250 sounds insanely high. Please let me know if this answers your questions.