this is in my continual quest to add useful information to our performance section. i'm also adding the links to this stuff into the wiki. feel free to add to it. BUT here's how to do it, translated from the dutch. NOTE THIS IS DONE WITH A VESPA TUNER IN MIND.
p.s. this works on other sizes as well examlple: 14/12 to 15/15 or 16/16 etc. BUT other dellorto's past 16 do have more than one main jet, so stick to the smaller sizes MMMKAY?
What tools do you need:
Very small-screwdriver for removing the SPRAYBAR
8mm for the removal of the clamp bolt and the fuel hose connector. Flat-screwdriver to remove the chokelever, washer and etc. boxcutter for the removal of cotterpin and spraybar
dremel, and propane torch for removal of the nozzle holder.
Now you disassemble the entire carburetor with the removal of the spraybar being the most difficult, but can be done in a few minutes. First heat the nozzle holder with the torch. you must heat. it because the spraybar is fitted with a clamp, and needs to be heated to remove.
If you think this piece is hot enough, use the very small screwdriver in the biggest hole of the spraybar, and if you can move the spraybar left & right by turning then you can push it out. . can't move it? then it's not hot enough.
once it is where you can push it out,, then you can just pull the spray bar out with a pair of pliers.
should look like this after youre done.
From left to right:
-Enclosure with plastic wear and clamp bolt
-cover
-cotterpin & fuel valve
-choke lever screw and spring
-choke lever bolt, fuel filter
-spraybar rule needle, washer and spraybar
now you can decide how big you want to go. (but DO THIS VERY SLOW AND ON A VERY SLOW SPEED)
11?
12?
13?
after you've cleaned the inside of the carb back up you Now you mount the spraybar with the 2 holes to the side where you put the carburetor on the crankcase. and reassemble the rest of the carbuerator
this will actually only take you about 30minutes if done correctly
and blamo! 13:13 dellorto!!
you can do this with all the other dellorto sizes as well!