exhaust sludge

Hello everyone I own a 01 cr125r and there is this black sludge running out
my exhaust pipe any ideas on what this is and how to fix it any help is
greatly appreciated

 

It's just 2-stroke "mung", which is carbonized oil that has thickened
and runs out around the exhaust pipe joint. If you're doing a lot of
slow running, the mung accumulates in the bottom of your crankcase and
then when you ride a little harder it gets blown out the exhaust pipe,
with some of it escaping...

You may even have some mung built up in a curve of the exhaust pipe if
it hasn't gotten hot enough to vaporize any liquid and turn into
carbon...

 

Hey youve invented the Scott oiler

 

Back in the early days of the last century, some motorbikes were
equipped with a one-shot oiling system. They had a Pilgrim pump. The
oil went through the parts it had to lubricate *once* and then dripped
onto the road. It wasn't such a bad thing, considering that roads were
dirt and the oil helped keep the dust down...

Early Kawasaki Z-1's were equipped with a pump attached to the
swingarm, as I recall. When the arm moved up and down the chain was
oiled. Too much oil, according to what I've heard, riders removed the
pumps...

 

Thanks for the help everyone

 

if your bike is spitting out oil of the exhuast it sounds like u are
jetted to rich. u should be able to run ur fingure in ur exhaust and
yor fingire should not be coverd in oil

 

ok I leaned out my jetts it seemed to help a little butt there is still
sludge comming out the pipe and the bike blubbers in the top of mid range
just before power band kicks in it kind of feels like its flooding any
ideas?

 

Your engine is "four-stroking". It's hitting on every other compression
stroke because it's too rich.

Move the e-clip on your needle UP one groove to lean up the part
throttle operation, ride it and report back here.

 

The exaust is supposed to spooge a little. That is what keeps your rear
brake lubed.

 

The first thing to check is whether you are using too much oil in the fuel.

ken

 

DING DING DING, we prolly have the obvious winner. Good job Kenny, hate to
find out this guy thought 50:1 meant 50/50 gas oil...


kenny enlightened us with:

 

Trying to cover up a jetting error with a hot spark plug can lead to
burning holes in the top of the piston when the engine starts pinging
badly.

A rider should not stray more than ONE heat range hotter or ONE heat
range colder than specified, and should know what pinging sounds like.

 

Absolutely. The only time I recommend this is when someone rides int
eh lower half of the rev range almost exclusively.

The only time I've ever had to go colder is when hotrodding a small
bore four stroke motor like a KLX110, for instance.

MX Tuner

 

the problem only occurs after riding (preaty much wide open all the time)
for awhile and only in 4th & 5th gear
my ratio is correct

 

If you're running 3/4 throttle, you're still running on the needle's
taper, so you can drop the needle by raising the clip a notch or even 2
notches.

If you're running full throttle, wide open, and you still get
blubbering, you need to install a smaller mainjet. Don't go more than
about 4 sizes maximum. Like if you had a #110 mainjet, and you
installed a #100 mainjet, that is four sizes smaller, because there's a
108, 105 and 102 between the 110 and the 100...

 

Excellent advice.

But, is your fuel air ratio correct?

Very good advice, although I wouldn't recommend going down more than
one size main jet at a time. (ride and test between changes.)
I still like the advice about the moving the needle clip up a
groove.

If the bike is blowing that much spooge, then the exhaust pipe may
need to be emptied and the silencer repacked before jetting can be
correct. You'd be surprised as to how much spooge some pipes can be
holding. The power valve may even be sticking from the cooked on
spooge.

I used to always be able to tell when my silencer demanded to be
repacked. It would catch fire on long (1 mile + straight stretches.)
Now, I just repack it before it gets that bad.



Jim Cook
'04 Gas Gas DE300 Woods Pilot
Team LAGNAF
SMACKOVER RACING
BJEC/SERA/TSCEC/AHSCS
www.smackovermotorsports.com

 

ok its as lean as i care to go helped a little but still sputering could
this be clutch? maybe reeds?

 

What does the spark plug look like? Is it wet with fuel or oil when you
run hard, or is it white as bone? If the plug is wet and fouled from
running at fuel throttle you need to lean up the main jet.

Your carb comes with a #360 or #380 hexagonal mainjet. There are jets
in the OP Carburetor fiche from 300 to 440 so owners can tune their
engines for running at high altitude and in hot weather.

The standard air atmospheric conditions that the carb is set for from
the factory is sea level and 59 degrees F. If you are running at 3000
feet and the temperature is 86 degrees, the correction factor is 0.92,
meaning you'd probably want a 330 main jet instead of a 360.

http://hondaex.com/techtips/carb101.htm (Look at figure 9)

The clutch would have nothing to do with sputtering. You might have a
damaged reed petal though. The carburetor doesn't know which direction
the air is flowing through it and will pick up a doubleshot of fuel.

Other possibilities are that the air filter is over-oiled or dirty, the
floats might be set too high, or the choke might be on all the time.
The "choke" isn't a plate like on a car, it's a little valve in the
carb that sucks fuel straight out of the float bowl. If the valve
leaks, your mixture could be too rich.

 

What did you change? How lean do you care to go? What circuit? Did you
try the pilot jet?

Tell us what you *did* do.....

MX Tuner