Dirty Carb/intake chamber after 3x3 and JD kit

I'm looking for some opinions on what would cause this kind of filth in less than 200 miles after 3x3 and JD kit. The carb was clean when the jet kit was installed. I followed the JD instructions and installed the 155 main, red needle on clip position 3 (Arizona heat, 2500-4500ft elevation), kientech extended screw 2.5 turns out. Runs like a raped ape, slight backfire during decel at high RPMs. Stock pipe. The only reason I found this is because the float malfunctioned causing fuel to pour out the vent tube. Noticed some corrosion on the float needle. Wasn't there when I rebuilt the carb 250 miles ago. Brand new UNI was in during the 200 miles. No dirt between airfilter and carb, all filth is between intake valves and within the carb. Please help. Backfiring through carb cause this? Hope the pictures work.





where are you in az,recently did jd rejet, i run the blue needle.550 ft asl though. I have no answer for you bit i'm interested to find out whats causing this, gunk is getting in somwhere..looks rich, but i'm no expert.

Looks like maybe too much filter oil.

I'm in Tucson and switched to the blue needle today while I was in there. Third clip from top.

I could see oil causing some gumming, but there is nothing between the filter and carb. It's clean and oil free. Just the carb itself is dirty. The filth on the intake side is almost like carbon build up and looks burnt, like it's backfiring through the carb. I just don't know if it was. Didn't sound like it, more sounded like a sharp pop through the exhaust during high RPM downshifting. I really wasn't concerned with it until I found this.

Edited by NateSD

bump..let us know what you find that caused this..

Unfortunately, I have no clue. I have since cleaned the carb and put the blue needle in on clip 3 to see if it's better. I will break the carb down again after another ride or two and see if it's happened again.

what filter are you running

My carb throat and cylinder head intake port were absolutely covered with a slightly-sticky carmel-coloured varnish.

But the bike ran fine, for the most part. I'm going to a new filter and wondering about flooding. I hadn't changed the filter since purchasing the bike.

looks like dirt ingestion to me.

Intake boot not fully lined up with carb intake?

The filter that was in it was a brand new UNI. I currently have a No-toil in it. I just swap them out every couple of rides and clean and oil the dirty one so it's ready.

I'm going to triple check my air filter box for holes/tears and make damn sure the boot is on properly. I didn't see any thing out of the ordinary when I broke it down to fix the carb. I am, however, starting to second guess myself with questions like, 'was the filter installed properly?', or 'was the boot attached to the carb properly?.' I hate not knowing what may have caused a problem. I will keep a close eye on it. I just hope there's no serious engine damage. I'm also thinking I may go back to the red needle on clip 3. Seemed to run stronger. Any suggestions there?

Well, something caused the problem, so thwart it by double-checking everything when you do the re-assembly!

Then I doubt you'll ever see THAT problem again.

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