2003 Xr650r Jetting Question

03 XR650R I bought this bike used last fall but it still had the rubber nipples on the tires and no sign of wear on the cases and no dirt underneath the bike or under the plastic at all so it is pretty much like new. When i got it home i had it uncorked. I put in the HRC exhaust tip and removed the things out of the air box. I had the dealer put in the carb manifold, carb needle and seat B53E 16012-MBN-641, MAIN JET #175 99101-357-1750, PILOT JET 68S 99105-MBN-0680. I am in Ohio at 1549 ft above sea level. I had the normal thing where the bike reved some on its own and the idle would hang and not go down for a few seconds and i also had the gas leaking out the tube when tipped to the side but after some riding these things went away on their own. It also took a while to find the right idle speed where it was easy to start but not idle to high but i have it going now where it starts easy but idles low. Here is my problem. After I had it rejetted and working thru the other problems the bike runs pretty good and starts easily but after 3 or 4 rides it eats a plug and won't start till I put in a new one. I didn't use that many plugs when i was riding two strokes. It runs good at all levels of rpms so I don't know why it is eating plugs. I had the suspension done, taller bars and seat, bigger foot pegs. It is fun but the plug thing is getting old. Any help would be great from people who really know the bike. :ride: Thanks Rick

Don't know if you tried the jetting forum, but I am finally done with the jetting my 05. I'm at 4600' and went back to the 65 pilot, and 162 main. The needle is still in the middle and the other stuff is like you did. The 68s or the 65 was a close one with the 65 resulting in more choke time, so I used that one figuring it would help with hot starts or flooding after a dump. The main just would not work richer than about the 162, I started low near 158 and went up to 175. At my altitude, it was really boggy. I've looked at 3 plugs and while the 175 wasn't dripping, it was black and the 162 is brown. I'm thinking maybe you could lean the main out some and see what happens...

From the setup you have, I think you should be running the needle at the 4th spot from the top, a 172-175 main jet, and a 70 or 70S pilot jet. The main jets & the 70 pilot jet are standard Keihin parts, so you can get them anywhere. The 70S pilot jet is prefered, but I'm not sure the part number. Tell the parts guy to look it up as a Honda part.

If you're running the stock air filter, I'd recommend ordering a Twin Air Power Flow kit. Got mine from Bike Bandit.com.

After all is set up, start & warm up the bike. You might have to adjust the idle just a bit, but mainly the pilot adjustment screw. Start at 1.5 - 2 turns out and play with it 1/4 turn at a time until you feel low-end performance is at it's best. Right = richer, Left = leaner. The pilot jet always likes being a bit rich.

My setup is almost identical to yours. Except I cut out the holes in my airbox side panel and riveted screen to them. Doing that will require 1 size larger main & pilot jet. I ride at 5,000 ft. or higher, and I run a 170 main and a 70 pilot. Before the cut out side panel, I ran a 168 main, and a 68S pilot jet. My pilot adjustment screw is currently 2.25 turns out. My HRC needle has always liked being at the 4th spot from the top. All this was with the TwinAir PowerFlow kit installed.

The gas dripping from the side while leaning is a slightly mis-adjusted float. You have to VERY SLIGHTY bent the tab on the float that holds the needle so the fload sits slightly lower in the bowl. In other words, bend the tab up.

Thank you both for the replies. I forgot to tell you it is in the third position and the pilot screw is out almost two turns out. I did notice when i turn the pilot screw and it had the most snap on the bottom I was starting to get some popping out of the exhuast so I settled on a mix on least poping but still good power. I am no jetting expert as you can tell and most of what I have learned about it is from this forum. Thanks again, anymore opinions would be welcomed but if not i will start going down some on the main and readjust everything. RICK

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