Question about warranties, and lemon law?

I bought a brand new scooter from a dealership. I liked it after test driving it, and thought it ran great. I bought the scooter for $1300. 5 weeks after owning the scooter, the battery went dead and would not start the scooter. I called the dealer who sold it to me. He said he would be happy to take a look at it. He came out to my house and took the scooter back to his place of business to look at it free of charge. He then called me, stated that the battery was weak, that the warranty does not cover wear and tear items such as the batteries, tires,clutch,etc., and that he would not charge me to put in a new battery as a one time good will jesture to make me happy. He then installed the new battery, checked everything over on the scooter to make sure it was in sound running condition, and returned the scooter to my home. He did not charge me for the battery, or anything else. Three weeks later the scooter was not running right as it would stall or idle improperly. I called the dealer again and complained. He stated that to me that everything was in great condition when he had the scooter the last time to put in a new battery, and asked me what I did to it. He said that he doubts anything is wrong with the scooter, but he would be happy to take a look at it again. I declined to have him look at it again as I was lead to believe I bought a lemon scooter. Another four weeks passed, and the scooter had 160 miles on it. Then, the rear wheel locked up on the scooter and would not move. The scooter would not start as well. I called the dealer again and complained. The dealer asked me what I had done to it, and I said nothing because all I did was ride the scooter around town. He said he would come out immediately to take a look at the scooter. He then came out to my house and took the scooter to his place of business. One day later he called me and said the clutch in the engine of the scooter is totally destroyed, that typically clutches in scooters last at least 1-2 years on average, and that something abusive had to be done to destroy a clutch within such a short period of time. He said that the warranty does not cover the clutch, or the labor to repair or install a new clutch, and that he would have to charge me $100 for parts and labor to install a new clutch in the scooter. I complained back to him that he sold me a lemon, and that I either want a new scooter, or a refund back. He then replied back that all sales are final, with no refunds, or returns, and that I signed the warranty agreement, and the bill of sale that stated all of what he claimed. He also stated that lemon law does not apply to scooters, motorcycles, or mopeds in our state of Pennsylvania. I then threatened to sue him for selling me a lemon scooter, and hung up on him. My question is, do I have a case to sue him for a defective product, lemon law, express warranty, fitnness of merchanibility, or any other legal standpoint? The next day he called me back, and offered to either fix the scooter for $100, or buy back the scooter for $700. I declined both as I feel he should give me all of my money back. He then stated that he is under no obligation to fix the scooter for free, or give me a full refund back, and that he offered to buy back the scooter just because he said he doesn't let his customers hang. What do you think?