I have a Derbi SLE Variant, vintage 3/1983, that I just got out of storage after several years of non-use. In fact, it has hardly been used, with only about 300 original miles registering on the odometer. I bought it brand-new. A friend of mine took the carburetor apart to clean it, and when he put it back together, it leaked fuel through the screw-down cap on top of the carburetor when running. Obviously, that has to be fixed. I think the cap on the carburetor needs to be replaced. Sorry for the lack of proper phraseology in regard to the part, but I'm definitely no mechanic. Anyway, does anyone know where I can get a part for my moped? All I need is this one little part to the carburetor, and I'm off and running again. The moped is in beautiful shape, and begging to be ridden. Thanks, Bill P.S. How do I establish a value on my moped? Is there a credible service that establishes values on older mopeds?