The problem below was solved by rebuilding the bottom end. Esp new crank seals. All on Kawasaki's tab.
Bike starts well each ride, one kick, often w out choke.
====================
Have 04 KX250. Plenty of plug fouling.
(See startup patterns at end)
Tried what dealer recommneded (seems like a cop out rather than a fix) - less choke and high revs all the time - not always possible - could cold sieze.
Hotter plug NGK B8ES as well as other dealer recommended plugs.
High octane gas.
Many starting techniques tried.
Have read many posts on diff forums, all say change main and pilot jet to leaner. Tweaked air speed screw to my elevation. Raise needle clip. (each in 1 step increments)
Mix is 40:1. Recently even tried 45:1. Started w Kaw racing oil, went to honda.
Appears that float might be sticking, although dealer says it's ok.
This is more comlicated than it needs to be. Haven't changed jets, needle yet. Dealer disagrees with changing any jets, needle. Say could cause serious problems.
Appears to be fuel related, but to me seems carb related more than anything else. One post said that the trans oil could be leaking in thru main seal at end of crank, but tran oil level stays in good shape.
Today? I am leaning towards changing jets, needle. What else is there?
Here are some patterns:
===Pattern A===
-bike sits with fuel in tank, line, carb. Could be over night or 30 minutes.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-plugout is usually wet due to flooding, no spark at electrode
-starts right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Power difference between fresh plug v after 30 minutes riding is BIG. Fresh plug = hang on tight, immediate strong low end torque. AWSOME! Then things get mellowed out. Not as jumpy on low end. Still good on high end.
===Pattern B===
-after prior ride, turn off gas, run engine until all gas is out of line and carb.
-bike sits with fuel in tank over night.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-start right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Same power difference between fresh plug v after 30 minutes riding.
===Pattern C===
-after previous ride, turn off gas, run engine until all gas is out of line and carb.
-bike sits with fuel in tank over night. carb empty, line empty. Tip bike on side to make sure any remaining fuel is drained.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-start right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Same power difference between fresh plug v after 30 minutes riding.
Best success with draining all fuel from tank, line, carb after ride. BUT I DON'T THINK I SHOULD HAVE TO DO THIS.
-----
Have tried other techniques but same problem almost w each day's ride.
===HISTORY 2005-05-28 Mods, Test, Fouling Persists
First, I'd like to thank every one for pitching in their views. Always, welcome and appreciated.
a. Reduced main jet one size down from #165 to #162 (this is how they are numbered).
b. Reduced slow jet one size down from #52 to #50 (ditto numbering).
c. Kept Needle Position in #2 position, unchanged.
d. Air filter very clean.
e. Trans oil was consumed during period of time from after test ride to next day am. Dropped from showing 1/3 in window to non-visible. NO TRACE OF EXTERNAL TRANS OIL LEAKS. Gotta be going somewhere. This may be cause of initial fouling, spooge, excessive oil burning at start of each day.
f. runs a little warmer, but not excessive.
g. power range is good from 1/4 throttle and up.
h. idle much better.
i. examined plug - dry & black w/ non-gassy smell, (formerly wet, sooty, gassy smell)
j. Examined float: operation is ok, no obvious obstructions to movement, carb was formerly tilted some, installed so float does not move at angle. Chkd for holes, no gas inside float.
Cold Start after mods:
-started & ran for about 45 secs w choke.
-top of radiator started to get warm.
-during that time, tried to turn off choke but wanted to stall, feathered throttle very slightly
-fouled plug
-put in new plug & started up, no choke
-plenty of spooge, thick smoke, moderate revs, seemed like it was going to foul also, but burned past thick smoke. ran ok.
-rode for a while, great power in full range.
-hand refurbed fouled plug, installed, started up, no choke, ran well, rode some more.
! We'll see what happends next startup. Will need to add more trans oil though.
The amount of spooge at the beggining of each day is way too much than what could be extracted from gas in carb - let's say starting with petcock off.
Did the math last night. So far from brand new, used 7 tanks of gas (on 8 now), 18 rides, has fouled plugs 50 times. Has fouled @ start of each ride day, even w new plugs from getgo. This is, in my opinion way out there! Dealer says its starting and riding style that causes this. Geez! I'm not as stupid as dealer implies. Esp since I've followed Kas and Dealer's recommendations by the book. Have moved on to concepts like you all's.
Thanks for the views. I'm looking at this with all angles.
Thanks to every one.
Problem still there.
Edging toward replacing crank seals. I think dealer should pay for it. What do you all think?
Bike starts well each ride, one kick, often w out choke.
====================
Have 04 KX250. Plenty of plug fouling.
(See startup patterns at end)
Tried what dealer recommneded (seems like a cop out rather than a fix) - less choke and high revs all the time - not always possible - could cold sieze.
Hotter plug NGK B8ES as well as other dealer recommended plugs.
High octane gas.
Many starting techniques tried.
Have read many posts on diff forums, all say change main and pilot jet to leaner. Tweaked air speed screw to my elevation. Raise needle clip. (each in 1 step increments)
Mix is 40:1. Recently even tried 45:1. Started w Kaw racing oil, went to honda.
Appears that float might be sticking, although dealer says it's ok.
This is more comlicated than it needs to be. Haven't changed jets, needle yet. Dealer disagrees with changing any jets, needle. Say could cause serious problems.
Appears to be fuel related, but to me seems carb related more than anything else. One post said that the trans oil could be leaking in thru main seal at end of crank, but tran oil level stays in good shape.
Today? I am leaning towards changing jets, needle. What else is there?
Here are some patterns:
===Pattern A===
-bike sits with fuel in tank, line, carb. Could be over night or 30 minutes.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-plugout is usually wet due to flooding, no spark at electrode
-starts right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Power difference between fresh plug v after 30 minutes riding is BIG. Fresh plug = hang on tight, immediate strong low end torque. AWSOME! Then things get mellowed out. Not as jumpy on low end. Still good on high end.
===Pattern B===
-after prior ride, turn off gas, run engine until all gas is out of line and carb.
-bike sits with fuel in tank over night.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-start right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Same power difference between fresh plug v after 30 minutes riding.
===Pattern C===
-after previous ride, turn off gas, run engine until all gas is out of line and carb.
-bike sits with fuel in tank over night. carb empty, line empty. Tip bike on side to make sure any remaining fuel is drained.
-start w fresh plug. warm up minumal choke, then warm rest of way w/out choke.
-runs for a short time, fouls plug. Put 2nd new plug in.
-start right up
-spooges out exhaust for couple minutes, burns a lot of oil, then burn normal oil/smoke.
-runs for rest of day ok.
-Same power difference between fresh plug v after 30 minutes riding.
Best success with draining all fuel from tank, line, carb after ride. BUT I DON'T THINK I SHOULD HAVE TO DO THIS.
-----
Have tried other techniques but same problem almost w each day's ride.
===HISTORY 2005-05-28 Mods, Test, Fouling Persists
First, I'd like to thank every one for pitching in their views. Always, welcome and appreciated.
a. Reduced main jet one size down from #165 to #162 (this is how they are numbered).
b. Reduced slow jet one size down from #52 to #50 (ditto numbering).
c. Kept Needle Position in #2 position, unchanged.
d. Air filter very clean.
e. Trans oil was consumed during period of time from after test ride to next day am. Dropped from showing 1/3 in window to non-visible. NO TRACE OF EXTERNAL TRANS OIL LEAKS. Gotta be going somewhere. This may be cause of initial fouling, spooge, excessive oil burning at start of each day.
f. runs a little warmer, but not excessive.
g. power range is good from 1/4 throttle and up.
h. idle much better.
i. examined plug - dry & black w/ non-gassy smell, (formerly wet, sooty, gassy smell)
j. Examined float: operation is ok, no obvious obstructions to movement, carb was formerly tilted some, installed so float does not move at angle. Chkd for holes, no gas inside float.
Cold Start after mods:
-started & ran for about 45 secs w choke.
-top of radiator started to get warm.
-during that time, tried to turn off choke but wanted to stall, feathered throttle very slightly
-fouled plug
-put in new plug & started up, no choke
-plenty of spooge, thick smoke, moderate revs, seemed like it was going to foul also, but burned past thick smoke. ran ok.
-rode for a while, great power in full range.
-hand refurbed fouled plug, installed, started up, no choke, ran well, rode some more.
! We'll see what happends next startup. Will need to add more trans oil though.
The amount of spooge at the beggining of each day is way too much than what could be extracted from gas in carb - let's say starting with petcock off.
Did the math last night. So far from brand new, used 7 tanks of gas (on 8 now), 18 rides, has fouled plugs 50 times. Has fouled @ start of each ride day, even w new plugs from getgo. This is, in my opinion way out there! Dealer says its starting and riding style that causes this. Geez! I'm not as stupid as dealer implies. Esp since I've followed Kas and Dealer's recommendations by the book. Have moved on to concepts like you all's.
Thanks for the views. I'm looking at this with all angles.
Thanks to every one.
Problem still there.
Edging toward replacing crank seals. I think dealer should pay for it. What do you all think?
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