Spoogey Stuff on Carb Slide - Normal?

[Smit-Dog]

Pulled the slide out of the carb for the first time. Bike has close to 2000 miles on it. KTM 2004 200 EXC.

Noticed all this spoogey stuff on the intake face of the slide. Is this normal?

I just wiped it off, changed the needle, and put it back in.

FWIW, running Klotz R-50, 40:1 (but ran it at about 36:1 for the first 1300 miles). Using No-Toil air filter oil. Intake boot behind air filter is always clean... other than a very small puddle of filter oil. Wiping with finger, it's clean. Carb cap is snug, hose clamps are tight. Carb vents are routed up into the air box (ala' PC Racing vent kit).

Is this normal after a couple thousand miles? If not, any ideas as to the cause?

Thanks!

 

[ellandoh]

just a thought ........do you lube your throttle cable?

 

[Smit-Dog]

Yes, I have lubed the throttle cable. I could see the lube oil running down the cable, and down the needle, but not accumulate back up on the slide face.

:think:

 

[ellandoh]

:think: :think:

 

[Rich Rohrich]

Smit - Are you running filters on the end of the vent lines, or are they just routed into the air box? This looks like normal draw through gunk from unfiltered vent lines.

 

[Smit-Dog]

The vent lines that run up to the air box go into a little plastic box with a very coarse foam element. I use No-Toil on the element, but it is so damn coarse... kinda like the foam element in the mouthpiece of full-faced helmets. Doesn't appear to stop any real dust, and the oiling of this element is probably not doing a whole lot.

Attached are pictures taken when the vent kit was installed (and the bike was obviously new!).

There are also the vent lines that drop down behind the swing arm that aren't filtered.

Is the gunk on the slide anything to worry about? Any suggestions? Should I provide better filters for the upper vent lines and/or lower vent tubes?

Thanks!

 

[Rich Rohrich]

Is the gunk on the slide anything to worry about?

It will probably increase slide, needle, and needle jet wear but that sort of wear comes with the territory on any dirtbike.

Any suggestions? Should I provide better filters for the upper vent lines and/or lower vent tubes?

Providing better filtering might help BUT, if you cause a pressure drop on the end of the vent line due to a restriction from a better filter, you'll be chasing your jetting forever.

It looks like your setup up is pretty smart as is. Given your mileage it's clear you aren't hurting the engine, so I wouldn't fix what isn't broke. ;)

 

[Smit-Dog]

... Given your mileage it's clear you aren't hurting the engine, so I wouldn't fix what isn't broke. ;)

Cool... that's what I was most worried about. Had me second guessing my choice of No-Toil filter oil.

Based on where this gunk is accumulating and how it's formed, it appears that the movement of the slide is scraping the gunk up as it returns. It's clean where the incoming air would hit it in its down position.

Any chance it could be the pre-mix oil (Klotz R-50) just collecting and gunking up on the slide? I used to run a higher oil ratio for the first year, but now run 40:1.

 

[LoriKTM]

For what it's worth, the slide on my 2000 200EXC never had build up like that. And the slide on my current '99 250 MXC never gets build up, and it's had over five good years of riding and racing. Also use No-Toil exclusively for both bikes, but do not have a PC Racing vent kit. Vent hoses are trimmed at an angle so they don't get clogged. Running Mobil MX2T at 40:1.

 

[ellandoh]

try lubing the throttle with it apart and see what comes out the end. it is nasty stuff , i dont do it with the slide in, or clutch cable either for that matter.

 

[Smit-Dog]

Worth a shot ellandoh, as it's currently apart. I'll try it tonight. I just don't see how the cable lube would drip down needle, then work its way back up and congeal like that.

 

[ellandoh]

i cant see it happening either but it can puddle up in their and over flow the edges, run down and dry id suspect and if done often enough :think: other than that i know that my slide, however is a different style is always moist regardless how long its been since ive ridden ....so i know its not straight gas and that leaves premix because AF oil is stringy when touched

 

[elf]

Smit, I use klotz r-50 in all my bikes at 32:1. I have never seen anything like that on my slides. So i don't think its the oil. I don't lube my cables either.

 

[hoosierf]

I bet that's filter oil. And I bet your vent tubes are drawing it in.

 

[Smit-Dog]

I bet that's filter oil. And I bet your vent tubes are drawing it in.

So you think that the vent tubes routed up to the airbox are drawing in filter oil?

The vent tubes terminate into a plastic box. In the plastic box is a small, very coarse filter element. I use No-Toil on this filter element, but I wouldn't think that the vacuum would be strong enough to draw oil from it.

:think:

 

[hoosierf]

It wouldn't take much and your gravity fed with the lines routed that way. Not saying its wrong, just my guess. you could take the lines out and stick a q-tip in there and see what comes out.