2000 honda cb250 I recently bought this cb250 and was going to do a tune up a saw that the plugs are milkish dark . (pic1 and Pic2) Pic1 http://i1315.photobucket.com/albums...3-19AC-48DE-8B2D-8C0BB6B98E70_zpskjw21zod.jpg pic2 http://i1315.photobucket.com/albums...3-A2F5-4E2C-B1A6-6A164FFE78AE_zps0puroqke.jpg Maybe Running Lean????? the spark plugs that came out was the NGK C6HSA. The previous owner gave me NGK C7HSA.I read on other forums that CR6HSA so went out and bought CR6HSA. Which is the correct spark Plug?? One more Question In Pic 3 below is these the adjusment for the Air/Fuel? what adjustment are in pic 4? Pic3 http://i1315.photobucket.com/albums...6-3DBC-49E6-A587-ECDE4988E269_zpsw2ax3pre.jpg pic4 http://i1315.photobucket.com/albums...C-D692-4055-831F-2BD1034A0D59_zps9zmpqsig.jpg
actually that brown colour is good fuel/air. if it was me i would keep using the c6hsa's. ORRRRR you could try the "brisk NAR15YS" and tell me if it gives you a 3% hp increase =p?????
Pic 3 is the drain screw for the fuel bowl. Pic 4, the black knob is for adjusting the idle speed. What plugs does the manual say should be in the motor? Try running the C7HSA and see if there is any difference. If not, the CR6HSA should work ok.
This is the only reference I found. http://www.manualslib.com/manual/784221/Honda-Cb250-Nighthawk.html?page=104#manual
A '7' is a colder heat range than a 6. If CR6HSA is the standard plug then go with that (unless you plan to run at Bonneville). The idle mixture screws would most likely be on the side or bottom of the carb bodies.
The air adjustment screw this down the neck of the carburetor intake you need a short screwdriver no corras mas que tu angel de la guarda pueda
