Motorcycle Repair: lack of power, air fuel mixture, gas filters

Question
Ive got a 1987 Ninja zx600r, It starts fine but when u take the choke off its really boggy and does not want to stay running,i have to keep reving it to get any type of power, plenty of spark, and is getting fuel. once I do have it started it goes from running good then boggy, back and forth, I can give it throttle and it will be really boggy, then good, then boggy. Thanks for any help u can give me on this...

Answer
Hi Mike,

Engine bogging is a sign of overly rich air-fuel mixture. Does the engine perform better with or without a bit of choke added? Spark plugs must be read to know what the air-fuel mixture is doing. Tune accordingly.

Otherwise, I suspect the carburetors may need cleaned and synchronized due to varbishing of the gas in the float bowls.

Other things to check:

Check the air filter and clean if necessary. Check gas tank and petcock for rust. If present, must be repaired (sealed). Once repaired, clean carbs again. Fine rust particles pass through gas filters. Particles collect in float bowls and obstruct jets and passage ways.

Send me your email address if you want carb cleaning, tuning, and synchronizing files returned to you.

Mark