Non-MX FCR 39 carb issue

I recently bought a 02 S model bike with very low miles (2k). The engine has a lot of good parts: 434 Athena BB, Hotcams, FMF Powerbomp w/Q2 muffler, 3x3 mod, FCR 39 with Eddie's jetting specs. I don't think the carb is the "MX" version. The body casting has the slanted look and it doesn't have a hotstart knob on it. I'm having 2 problems with it. First when starting cold the choke seems to over-choke it. It will flood easily yet when choke pushed off it dies. While cold with choke off it hesitates terribly and stalls. Once warmed up, it starts perfect but still has a slight hesitation taking off from a stop. Other than that is runs great. Any ideas? Does this carb need the o-ring mod also?

have you tried just pumping the throttle a couple of times and starting it with out the choke

Carb of unknowm origin could have a rich starter jet. You say it has Eddie's jetting but it may not be correct for an unknown carb. The OEM FCR needs different jetting than the aftermarket FCR MX. An unknown slant body may be different still.

Post the jetting to start with.

yes it will fire right up if I "pump" the throttle a few times, but it won't stay running and if I try to keep it running with the throttle it dies also

is the OEM FCR the slant body model? How can I tell if it's an OEM model or aftermarket?

Any itty-bitty numbers and/or letters stamped or printed on the carb body just above the float bowl gasket area?

Also, a pic from both sides of the carb is handy.

If it is indeed a DR-Z400E FCR39, when jetted to Eddie's recommended specs and there are no faults with the carb, itself, it should start and run like a dream.

This is what's on my bike (2009 DR-Z400SM), and the installation couldn't have been any easier.

The bike starts easily in any weather and runs flawlessly.

My bike has a similar setup to yours, too:

3X3 airbox hole

FCR39 from DR-Z400E with Eddie's jetting specs

Stage 1 Hotcams

Cylinder Works 94mm big bore kit

FMF Powerbomb header

FMF Q2 muffler

If twisting the grip a few times on cold start gets the bike going, it is not a lean choke condition, rather it is not rich enough. Try a larger starter jet.

The starter jet is definitely too rich. It may start and die with the choke on and to get it restarted I have to push the choke off and hold the throttle open slightly. Of course, once it starts it won't stay running unless I keep playing with the throttle until warmed up. I'll check for the small numbers-letters near the fb gasket and take some pics as soon as I get back. I have to leave town until Friday and won't have internet access.

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