I have a 1978 Kawasaki kz650. I cleaned the carbs, changed the oil/ oil filter, and change the spark plugs. When changing the plugs they where black. I know its running rich, so I adjusted the piolet jet. It runs fine when I am up and going. I just cant hammer it from a stand still. I have staight pipes on it as well. I am thinking of putting smaller main jets. Anything will help a tons. Thanks!
2007-04-02 06:03:52 · 5 answers · asked by Marc V 1 in Cars & Transportation ➔ Motorcycles
like guardrail said, changing the jets wont help. u really need to take the straight pipes off. they're the worst choice of pipes for street riding. dyno sheets have proven that straight pipes hurt street performance; the engine wont even wake up until past 4500 rpms.....and u'll never be in that area even on the interstate unless ur at full throttle. u'd get much better performance with a slightly louder than stock pipe. check what guardrail suggested also.
2007-04-02 10:04:09 · answer #1 · answered by Anonymous · 2⤊ 0⤋
Black plugs could mean rich jetting, but could also be oil deposits from sloppy pistons, etc.
I second the opinion on the straight pipes, if you've still got the stockers (or some good mufflers for the headpipes you're running), put 'em back on.
After that, you will need to re-jet. Here's a great site with some basic information about what each jet circuit does, and how to check jetting: http://www.powroll.com/tech_specs_jetting.htm the company doesn't sell anything for your model, but their jetting info works for any engine.
2007-04-02 12:29:37 · answer #2 · answered by ducatisti 5 · 0⤊ 0⤋
Check the valve clearance. Tight valve clearance can cause these symptoms.
Running straight pipes will not give the exhaust enough back pressure. That would mess up engine performance.
The valves might be leaking. Running straight pipes can burn the valves. Perform a cylinder leak down test to check for valve leakage.
A jet change will have no affect on acceleration from idle.
2007-04-02 06:52:00 · answer #3 · answered by guardrailjim 7 · 2⤊ 1⤋
hows the advance working, also straight pipes on a rice brner ar a recipe for disaster (burnt,warped valves, these engines were design for a certain amount of back pressure
2007-04-03 09:54:54 · answer #4 · answered by macautobody 1 · 0⤊ 0⤋
Let the clutch out at 5000 rpm.
2007-04-02 06:20:35 · answer #5 · answered by Anonymous · 0⤊ 1⤋