Plugged muffler?

[mudpack]

Anyone ever have the stock muffler clog up to the point it effects the running of the engine?

Last week I was on my return route after riding about 10 miles and the engine on my '06 KDX200 started running "funny"; the top end was not crisp, had a funny sound on overrun, and would not idle. It was down on power everywhere, especially on top. When I got home, there was tremendous spooge on the bike around the pipe/muffler joint.
I pulled the airbox and carb off last night, everything looked clean. I'm wondering if the spark arrestor is plugged. I plan to do the "rubber-hammer/muffler plug out" routine today (never did it before) after work and see what happens.
Anyone had success cleaning out a stock muffler and how did you go about it???
Thanks

 

[julien_d]

As far as I know, removing the drain plug and beating on it with a rubber mallet is the only way. I'd even start it and try to blow some of that crap out the drain hole. I guess you could throw the thing in a campfire and let it burn out?

 

[pesky nz]

YOU MAY RUN FOWL OF YOUR NEIGHBOURS but this method works on any steel muffler or chamber that is not repackable.
1 open top 5 galon container made of metal
2 quart of pertol
3 place engredients inside container and light (from a safe distance or loss of facial hair will result
4 cook muffler until petrol fire inside drum has gone out for itself
5 your spooge should now be dust and able to be blown out by motor
-
-
The muffler will have glowed red hot so external paint will likely be gone and need replacing. The burning should take about 1/2 to 3/4 hour.
ONLY START THIS OUTSIDE AND AWAY FROM KIDS AND ANIMALS AND HOUSES

 

[jaction125]

Dear god. Please don't do that.

 

[Joburble]

I'd do a quick lap around the block without the muffler just to see if the muffler was the problem. I know it won't run the best with the muffler missing, but it should let you know if that was the trouble.

 

[mudpack]

I'd do a quick lap around the block without the muffler just to see if the muffler was the problem.

This was the first thing I thought of. :cool:
I've ordered an FMF PowerCore2 for it: I'll put that on and then do a quick lap around the block........


Tried the factory-approved method of cleaning out the spark arrestor; nothing came out. I didn't expect it to with all the spooge.

 

[mudpack]

Put the new muffler on it.
Now it won't run at all under load. I can't describe what it is doing except it will barely pull under a load and sounds terrible.
Starts and idles fine, will rev under NO load, but but a load on it and it falls on its face.
I'm thinking "reed valves" and will start the tear-down in about 10 minutes....

 

[dirt bike dave]

Is your KIPS valve working right?

 

[sr5bidder]

This was the first thing I thought of. :cool:
I've ordered an FMF PowerCore2 for it: I'll put that on and then do a quick lap around the block........


Tried the factory-approved method of cleaning out the spark arrestor; nothing came out. I didn't expect it to with all the spooge.

Mud,
you have put a new spark plug in to eleminate a fouled/ damaged plug havent you???

 

[whenfoxforks-ruled]

Jetting, worn top end, or riding with the plugged silencer blew a seal/gasket?

 

[mudpack]

Found the problem: float bowl fuel level was too high. Been so long since I've had that happen to me that I didn't recognize it. :(
Appears that the rigid foam floats have absorbed some fuel, which makes them too heavy and raises the fuel level in the bowl. (I measured the float height and it is within specs, so a "waterlogged" float is the only answer.) I will order both a new float and the factory fuel level gauge tomorrow. The gage will let me set the level even with soaked floats.
Too bad I spent the $$ for a new muffler, but I'll just have to consider it my "stupid tax"! :)

Yes, a plug check was the first thing I did; it looks normal. I also pulled the KIPS cover off and ran the engine; it's going through the complete range of motion. Reeds are fine, too. Looks like everything is fine, mechanically!
Thanks for the suggestions, guys!! I should be back on the trails by Saturday....riding the ol' KLX450R is fun alright, but I really like my KDX....

 

[sr5bidder]

just had to ask about the plug seeings how you did not mention that you had checked it ...glad your back up anyhow :cool:

 

[motopsycho87]

I had the same problem with my float height quite recently, turns out someone had fitted the wrong needle valve (about 5mm longer), so it was impossible for me to achieve the the 6/8mm float height (PWM), I figured it must have just gone to the parallel lines on the carb, then it started wedging the needle and leaking so I ordered a new one, load and behold it was a completely different size, the height could be set properly and the bike ran well! HAPPY ENDING!!!

 

[mudpack]

Well, I found the problem and it wasn't the float level, or the muffler, or the reeds, or the KIPS.
I'm too embarassed to tell you what it was; should have been the first thing to check.
All is good, and the new FMF seems to add to the top end just enough to feel. I'm pleased.

BTW, I rode a customer's KTM 200sx at the shop this week. Man, that thing has a LOT more power than the KDX!!!
Felt more like a 250 motocrosser than an enduro.....but, it's also louder, pipey-er, and taller. Might be more of a handful for persons of short stature (like me) in the tight trails...?
I was also surprised at the crude rear suspension: it's not a link-type; the shock bolts directly to the swingarm. It seems to work fine, though. Different breed of bike, that's for sure.

 

[Joburble]

You can't leave us hanging Mudpack, what was it?

 

[whenfoxforks-ruled]

You can't leave us hanging Mudpack, what was it?

Come on, like you honestly believe you have done something new? For the thread Mudpack!

 

[pesky nz]

don't feel too embarased to tell us which step was overlooked so others can learn from it. Anyone who has fixed things has also bent broaken or totally stuffed something along the way

 

[helio lucas]

yeah, i have tried to rejet a bike with a fouled plug before... :yikes:

yep ALL of us have done quite embarassing things before... well, all but pred...

 

[Joburble]

If you're not going to tell us we will have to start guessing.

My guess is you mixed the gas wrong and accidently put too much oil in and a fresh tank of gas fixed it? Anyone else?

 

[dirt bike dave]

I'll guess the plug looked good but wasn't.

 

[whenfoxforks-ruled]

Dropped the plug, and darn near closed the gap?

 

[sr5bidder]

thinking the plug :nod:

 

[mideastrider]

:bang: Maybe forgot to push the choke off

 

[mudpack]

I'll guess the plug looked good but wasn't.

Ding! Ding! Ding! Ding! Ding!
...winner, winner, chicken dinner!
:cool:

 

[pesky nz]

just finished working on a bike yesterday that had good fat looking spark at the plug but would not go. If I had done that test properly I would have found the spark could only jump about 3 mm instead of the 7minimum and over ten once the weak stator was replaced.
Assumption really is the mother of all f.....ups as mentioned in Die Hard. Now if I could just get the memory to work properly I would not have to learn the same lessons over and over