This is called theft by receiving. The penalties for this felony crime are the same as if you stole the bike yourself. You are responsible for making sure you are not purchasing stolen items, therefore the theft by receiving charges.
You can be arrested for receiving stolen goods.
You can go to jail for theft of a car.
If you know it was stolen, yes, it would be illegal. If you purchase it through the police department, that would be legal.
The motorcycle is not there anymore.
You get charged with possession of a stolen vehicle I believe. If you knew it was stolen when you bought it then you are handling stolen goods (or a similarly fragrant nosegay of legalspeak, depending where you live) and the police will be keeping a close eye on you and they will be very interested in you. If you did not know it was stolen, then the motorcycle will be confiscated and searched so they can try and find out who had stolen it and where it came from. How you then get your money back, if at all, depends again on where you live.
Gsxr
There are many places where one can purchase motorcycle windshields. A good place where one can purchase motorcycle windshields is the website "eBay".
Yes.
A.C.V. (Actual Cash Value)and or (loan to value) blue books. Your purchase receipt will help determine the real value.
If there was a lien on the motorcycle for a loan used to purchase it the lienholder should receive the check. Any amount over the balance due on the loan should be sent to you. If you owned it outright and are the only person on the title then the check should go to you.
One can purchase a Scrambler motorcycle from a Triumph Motorcycle local store. One can also make such purchase using their official website or using the AutoTrader UK website.
If the Motorcycle is local you could try the local police, but chances are that stolen motorcycles are shipped interstate. You need to get the VIN from the motorcycle frame and get a report on this which will tell you what information is stored against this motorcycle. Look for other clues from the seller, are they too keen to sell, is the price too cheap?
Someone could purchase an automotive motorcycle at a local motorcycle dealership. There are also ways to obtain used motorcycles such as autotrader or craigslist.