40 Pilot Jet

[chris46250r]

I just bought a 07 400ex a couple weeks ago and I was changing oil and cleaning the filter this afternoon and I decided to up the 38 to a 40 pilot. Took the 38 out and it was a short stumpy pilot jet. I compaired it to the 40 I had and its exactly the same from threads up but it is a tad longer on the other end. The 38 was up in the hole a little and the 40 sits flush with it. I went ahead and put it in and it runs fine. I guess my question is whats the difference in the two other than the obvious? I looked at all the other 10 or 15 pilot jets I had from 250r's, CR's, 450r's and I dont know what else and they were all the same length. Whats up with this?

[GPracer2500]

Series 21 vs. Series 26. The Series 21 is more common. As you mentioned, the only difference is the length from the threads to the slotted end. My experience has been that in carbs that originally used the shorter Series 26, as long as the 21 physically fits in the carb without clearance issues it will work just fine.

[chris46250r]

Thanks. Like I said it sits flush with the hole it goes in and the white splash guard fits back in like its supposed to.