16-05-23, 11:10 AM
Hi. I would do (I did) this, to avoid an endless suffering with the carbs:
0. while engine running spray brake cleaner around carb boots to check if they're airtight; idle should not change
1. order full seal, gasket and O-ring kit from [ https://www.litetek.co/ ] (thai company, best quality and they have the proper sizes, quantities in their kit, and made of modern, ethanol infected fuel compatible materials (viton, etc.); don't buy from Yamaha!)
2. total carb disassembly, except butterfly + shaft
3. total cleaning with ultrasonic bath + compressed air, multiple times if needed, untill clean
4. check and replace every brass parts, which have signs of water (ethanol) erosion, or other damage
5. reassembly with new seals and new parts, put silicone grease on rubber parts while assembling
6. initial settings according to service manual (CO2 screw, etc)
7. carb balance, idle adjustment
8. success
0. while engine running spray brake cleaner around carb boots to check if they're airtight; idle should not change
1. order full seal, gasket and O-ring kit from [ https://www.litetek.co/ ] (thai company, best quality and they have the proper sizes, quantities in their kit, and made of modern, ethanol infected fuel compatible materials (viton, etc.); don't buy from Yamaha!)
2. total carb disassembly, except butterfly + shaft
3. total cleaning with ultrasonic bath + compressed air, multiple times if needed, untill clean
4. check and replace every brass parts, which have signs of water (ethanol) erosion, or other damage
5. reassembly with new seals and new parts, put silicone grease on rubber parts while assembling
6. initial settings according to service manual (CO2 screw, etc)
7. carb balance, idle adjustment
8. success