Hi kowalski the green supreme is much rarer than the 500 twin. As the 500 was indeed the first of the twins and was sold in larger numbers,however the gold supreme is even rarer than both. I'm still chasing one myself. About the weak spark on the rear cylinder,it was infact compression problems. There has been lots of talk on spark problems but it was infact compression problems. There has also been talk on revised coils. Through my experience there is no revised coils and I have done (and got a few twins) a lot of work with twins. I would be interested to know what the engine number of it is,as I'm trying to find some patterns with the numbers. If you have any questions on this twin or others please ask always happy to help.
