Thanks in advance for evaluating my AWA essay!

The following appeared as part of an article in the business section of a local newspaper.
"Motorcycle X has been manufactured in the United States for over 70 years. Although one foreign company has copied the motorcycle and is selling it for less, the company has failed to attract motorcycle X customers—some say because its product lacks the exceptionally loud noise made by motorcycle X. But there must be some other explanation. After all, foreign cars tend to be quieter than similar American-made cars, but they sell at least as well. Also, television advertisements for motorcycle X highlight its durability and sleek lines, not its noisiness, and the ads typically have voice-overs or rock music rather than engine-roar on the sound track."
Discuss how well reasoned you find this argument. In your discussion be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.
---------------------------
My answer:
The argument is claiming that the loud noise made by motocycle X is not the only or primary reason for the loyalty of motocycle X's customers.
There are several questionable assumptions that undermine the strengh of this argument. First, the author makes a generalization that foreign cars are quieter than American-made cars. However, cars and motorcycles are different products, each with their own unique set of purchase criteria. Quietness is not necessarily an attribute that people are looking for in a motorcyle. Another assumption is that the only variable that is different between American-made cars and foreign cars to determine how well they sell is their noise level. However, there are other important variables that they differ on. For example, in an extreme case, if an American made car was $25,000 and louder than a foreign car and a foreign car was only $5,000, then it's quite possible that price, not quietness, becomes the reason why someone would buy the foreign car over the American-made car.
It's also possible that the reason the foreign company has failed to attract motorcycle X customers is because American customers are not the target for that foreign company. The foreign company may be solely focused on advertising and selling to customers outside of the US. This means that some US customers may not know that this foreign company's version of motorcycle X even exists, and thus this option would not be considered when they are deciding which motorcycle to purchase.
Additional evidence could be included in the argument to make it stronger. For example, the author could have included information about the loudness, in decibels for example, of the sound produced by motocycle X compared to other motorcycles. If motorcycle X is indeed louder than the rest of the popular motorcyles in the motorcycle market, then this means that loudness is a differentiating factor for motorcycle X. While this wouldn't prove that customers value loudness when choosing a motorcycle, it would show that this is a quality unique to motorcycle X.
There is also evidence that could weaken the argument. For example, the author could include the results of surveys or interviews of people who have purchased motorcycle X to see what features of motorcycle X drew them to purchase it. If the results show that the loud noise that the engine makes is the most attractive feature, this would refute the argument because it would confirm that the loud noise is the primary reason for the loyalty of motorcycle X's customers.