Proper cleaning is the most important part of the service manual process.
A common starting point is 2 turns out from lightly seated, though this varies by bike model. Key Helpful Resources XJRider Rebuild Guide: The XJRider forum
The best source is the OEM manual for your vehicle (e.g., Hyosung GV250 Service Manual).
Comprehensive Mikuni BDS26 Go to product viewer dialog for this item. Service Manual Guide: Rebuild & Tune The Mikuni BDS26 Go to product viewer dialog for this item.
:
According to the Mikuni Tuning Manual , proper tuning is vital:
Standard sizes range from #87.5 to #90 depending on the cylinder (front/rear). Pilot Jet: Typically #20.
: Gasoline is explosive; work in a well-ventilated area away from sparks.
This guide serves as a comprehensive service manual to help you tear down, clean, and rebuild your Mikuni BDS26 assembly. Anatomy of the Mikuni BDS26 mikuni bds26 service manual
Before working on the carburetors, know your specifications. Note that FRONT and REAR carbs may have different jetting. Mikuni BDS 26 (Double) Bore Size: 26 mm Main Jet: #90 (Front) / #87.5 (Rear) Pilot Jet: #22.5 (Both) Needle Jet (N.J): O-6 (Both) Pilot Outlet (P.O): 0.75mm Starter Jet (G.S): 1.2mm Float Height: 17mm ± 1.0mm Idle RPM: 1,450 – 1,550 RPM 2. Required Tools & Supplies
If you experience fuel leaking into the intake after a rebuild, check the dimensions of the needle seat; even a 1mm difference in aftermarket kits can cause overflow. Fuel System | ATKUSA
It dissolves the diaphragm rubber and the plastic vacuum piston guide rings.
| Symptom | Likely Cause (per manual) | |--------|----------------------------| | Rough idle, one pipe cold | Clipped diaphragm or vacuum leak at that throat’s manifold seal | | Hesitation off-idle | Accelerator pump timing or nozzle clog | | Hard cold start | Enricher plunger not fully sealing (or cable slack) | | Rich surge at cruise | Needle clip too low (rich) or float height too high | | Poor hot restart | Fuel boiling – missing heat spacer gasket or low float | Proper cleaning is the most important part of
Spray aerosol carb cleaner directly into every single orifice, pilot circuit hole, and air bleed jet. Verify that fluid sprays out cleanly from the corresponding exit holes inside the venturi throat.
Carefully seat the diaphragm in its groove before tightening the top cap. 5. Tuning and Setup Once installed, the BDS26 needs to be synchronized.
For a complete overhaul, use a high-quality rebuild kit from retailers like All Balls Racing
Allow the float tab to lightly touch the spring-loaded needle rod without compressing it. Comprehensive Mikuni BDS26 Go to product viewer dialog
If you can tell me what you are experiencing (e.g., hard starting, stalling at idle, high speed hesitation), I can provide more specific troubleshooting advice. Alternatively,
