November 22, 200817 yr I was wondering if there was anyone out there with some experience with these carba. I wanted to know about slide number or type, needle number and low speed, high speed, and starter jet sizes??? Thanks.
November 22, 200817 yr Hi I put one straight off a Fantic 249 (212cc) straight onto my Mont 242. Ran a treat with no re jetting. Maybe wort starting wit an old carb straight off a trials bike. Probably wont be too far off.
November 22, 200817 yr I was wondering if there was anyone out there with some experience with these carba. I wanted to know about slide number or type, needle number and low speed, high speed, and starter jet sizes??? Thanks. Believe it or not, I did this swap on a friends Cota and it ran quite well. The oval port PHBH26CS (air screw model, known as the "large body" Dellorto) was off a 96 GasGas 338cc (JTR370) and worked essentially with the GG jetting (at sea level). MAIN: 115 PILOT: 45 NEEDLE: X18 (2nd CLIP POSITION DOWN FROM TOP) SLIDE: 55 AIR SCREW: 1.5 TURNS OUT TO START Jon ps. Forgot to add: These carbs often work well on the early bikes due to their throat bore design, which is oval (like the early four-stroke Keihin models) rather than round. This makes them act like a smaller than 26mm carb at low slide openings and maintains a higher velocity of air over the needle jet tower promoting better atomization of fuel and aiding the "idle circuit-to-pilot jet-to-needle jet" transition of the fuel/air mix. As for the starter jet, they often come with #60 or #70 and seem to work better with a #80 starter jet, or you can drill out the jet with a .8mm or .031" pin drill (best to do in a lathe if you have one). Edited November 23, 200817 yr by JSE
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