So yesterday afternoon after riding home from work I decided to clean the carb and downjet. This was my first time working on a carb. at all so please excuse my noobness. It's a stock Maxi with a Dellorto 14.12 SHA. Also, I recently de-rusted and cleaned the gas tank, which was pretty bad.
So the carb was in fact pretty dirty. My decision to downjet came from some signs that the bike was running rich. I had some other symptoms that were probably related to the carb being dirty - there was a bunch of rusty sediment in the bowl.
Anyway, I cleaned it and went from a 60 to a 58 jet. Put it back together, started it up and it ran great. Rode around town, seemed just as powerful as before, etc. However, I couldn't really get it to run this morning. It would start up, but want to die out when I revved it up. I had to give up and drive to work. I'm just wondering if going down 2 jet sizes could be enough of a change to cause this.
Since it ran fine yesterday afternoon, the only thing I can think is that the 58 isn't delivering enough fuel when the engine isn't warmed up and it was also cooler this morning (about 60 degrees vs. 75 yesterday pm.) In my noob mind 60 to 58 doesn't seem like a big change but maybe it is? I guess my next step is to take the carb off and maybe try a 59 or just even go back to the 60. Thanks for any input.