THE PROBLEM WITH CARBURETOR NEEDLE CLIPS: MR. KNOW-IT-ALL

EYE OF THE NEEDLE
Dear Mr. Know-It-All,
Here’s a good one for you. I recently was riding my ’08 KTM 300. Upon accelerating, the bike suddenly bogged out as if it had seized or fouled a plug. It still had compression and wanted to fire up but would not rev at all. So, I limped it home and popped the carb off. Upon doing so, I was greeted with the needle sitting in the jet block not attached to the slide. Upon further investigation, I found my E-clip split into two with only one piece in the slide. Searching for the other half, I was sly enough to remove the reed cage before firing the bike up again and found the other half sitting in the corner of the cage. Talk about being lucky. I ordered a new needle and e-clip from JD jetting and am now back on my way. How do you think this happened? I can’t believe how lucky I got.
Lucky Lou
via [email protected]

Oh, you’re a sly one, Lucky Lou, but please never vomit your accolades on any missive sent my way. Keep to the point and don’t play the wordsmith and you’ll go places. I’m going to speculate that you have made many needle clip position changes over the years and have never exchanged the needle, or clip, for a new one. I have never experienced this drama or seen it happen, but my best guess is that your needle’s grooves and the e-clip were fatigued and worn out from years of jetting changes. This most likely led to a little bit of play in the e-clip and the grooves. When you are turning your throttle and the needle is moving up and down with the slide, then factor in the air velocity going through the carb, it puts a lot of stress on that area. I’m guessing it finally just snapped. You have learned a valuable lesson, Lucky Lou; these are wear items and should be replaced periodically. Another staffer says this is because you gripped the clip with a pair of Vice Grips when removing it earlier. This is a no-no because the clip cannot flex as it was designed. You are always better pushing the clip off the needle against a hard surface.

And by the way, good job on Sherlock Holmes-ing the recalcitrant missing clip that was hiding in the reeds! Well done!