1999 XR600R Jetting and Uncorking

I just picked up a 1999 XR600R in SoCal for $1800 for my brother!! It runs good and starts good with the choke on. Once it warms up, it will cough and stall at idle if I am not carefull but will run fine as well with the choke off. I am assuming the previous owner might not have rejetted when he put on the pipe. I noticed it has more emissions stuff than my old 92 XR600. I went through the uncorking stuff on my 650, but I only had to change the jets on my 92. Is there anything special I have to do on the 99 such as an intake boot replacement (like on the 650)? What pilot and main should I run for about 2000 feet elevation? It has a supertrapp on a stock header.


Okay, I just noticed Baja Designs sells a kit with alot of parts. Looks like I was right about the intake boot. Also lookes like I have to replace alot of the little internals, like the needle, jets, and some other stuff. I have not looked into the carb yet to see what's in there. So if someone could give me some needle and jet numbers and tell me whatever else to check, so I can see if it's been at least partially or completely uncorked. The boot thing should be pretty noticeable.

I'm no expert, but my setup should give you something to compare against. I'm running a 68 primary, 160 main, and what I think is the stock needle in the middle groove. Runs just a hair rich at 3500ft+. Totally free breathing and I dont use the choke.

The information I have shows that the Kalifornya bikes do run a different needle (as well as the restrictor manifold you've found). The Cali needle is 16012-MAG-L01, and the 49 state needle is 16012-MN1-751. Actually these are the part numbers for the needle jet sets (ie both parts). Unfortunately I don't have the Keihin needle numbers (e.g. A16A, B53E, etc) to tell you, as they aren't in the service manual and I can't find them anywhere else at the moment.

Good info Hairy. Thanks.

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