I think I can tune fine. I believe I did break it in properly, since I went off of the manufacturers break-in process which was similar to many guides that I have seen posted on the Internet. I also agree that I should get more than 1 gallon out of it which is why I made this post.

Here is a little more background. I had the Traxxas engine for a while and eventually got rid of it because it wasn't that great. I broke that engine in fine and it lasted a few gallons before I replaced it. At the time, there were not a lot of .15's that would bolt right on to the T-Maxx, and the HPI 15ss was one of the better at the time. I purchased that and had that running great. I recall only running about a gallon through it, but it is definitely no more than 2. The 15ss always ran great, it was the truck that sucked. Eventually I got tired of always fixing it, so it sat on the shelf for a few years. I decided to give it to my brother and shipped it off to him. When he got it the weather was totally different and it needed to be re-tuned. After trying several times to tune it I gave up and took it in to the LHS. The guy there, which may be no better at tuning than me, wasn't able to do any better than I was. He felt that the compression was low. There didn't seem like a great deal of resistance to me either, but I hadn't used it in years making me a bad judge.

All the fuel lines were replaced to eliminate the possibility of having an air leak in the fuel line. The tank was new as well, so that seemed like an unlikely cause. It had new gas in it. The only other possibility in my mind is there is a leak in the carb, or it is worn and needs a rebuild.