Japanese Bikes, Build Threads & How-To’sBuild threads, tech Q&A and conversations centered around custom-built motorcycles from the Land of the Rising Sun
Please help me before I throw these carbs into the street. I was running 100 main jets but at the top of every gear it seemed to fall on its face. like i would have to shift way earlier than I should have to but it was really great at the lower end of the gear. I figured since I am running open headers that maybe I needed to jet it up a bit. I bought a jet kit went up to 115 and that seems to run crapy as hell at the bottom but decent at the top. So i went to 110 and now the damn thing just falls on its face all over the place. if anyone has a cb550F with open headers and can let me know which jets seem to work best for them please let me know otherwise Im pushing it off a cliff. thanks for any help or suggestions.
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Join Date: Oct 2009
Posts: 394
Honestly, the wizardry that goes on in carb tuning bewilders me (especially on Cb's) to the point that I just stopped trying to do it myself. Call me lazy, but I would take the bike to a shop with a dyno and have them do it right the first time and be done with it.
Have you synced the carbs?
What filters are you running? Pod filters, velocity stacks?
Have you tried running the bike with no filters to see how it does?
You might want to try CycleX's jetting on the fly option.
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Join Date: Jul 2012
Posts: 74
Thanks guys I think I will take them to a shop or someone that is better at carbs than me. One minute I think i got it then the more I ride it the worse it gets.
Im running pod filters and as of now have 110 main jets in. the only other issue I think one of the seals isnt sealing well on one of the bowls so i may try to see if I can get better seals for it. I think it might be sucking in some air.