Re: Fly cast without flies is great, but...
Have you actually measured how far? There is a difference in distance between your with and without flies of 50' to 70'. I'm not sure how big your bubble is, but that fly should not make the slightest difference. Your rod is an 8wt so you should be able to cast much much bigger flies. Is the fly/bobber hitting the running line on the final shoot so that the end of the mess is 30' and still getting the 80' to 100' of line out of the rod? Without a better idea of what's happening it would be hard to say. My best advice would be video tape yourself casting and look at it. More than likely you would be able to see the problem. If you still can't see the problem, post the video and someone here will be able to.