Keihin FCR 39 on a DRZ400S

I was buying a FCR39 on ebay to use on my ´05 DRZ400S. I am not sure what bike it was installed on before, so I guess I need to rejet it before installing it.

I ride from sea level to around 2000 feet altitude. Normal temperature is around 40-60 degrees. Of course I will enlarge the air intake when changing the carb.

Can anyone tell me the best jetting for this setup?


got a link to the auction?

oh,thats good.its a oem drz carb.

you will need the intake manifold,air boot,throttle cables and assorted clamps from a E model.

you to check what jetting it has.most likely pretty stock.

3x3 air box mod

160 mainjet (142 stock)

DXP needle (stock)

5th clip (4th stock)

45 pilot jet (stock)

2.5 turns fuel screw


Finally I´m installing the carb on my bike....

I´ve got two questions:

1. There is a breather hose coming from the crankcase, through a box and to the intake manifold. The "E" manifold I have now does not have a hole for this hose. What should I do with it?

2. The Mikuni I´m replacing did have 2 electrical plugs, 2 pin and 3 pin. The FCR does only have the 3 pin. Can I just leave the 2 pin plug as it is (not connected)?


you extend the vent line and run it down toward the ground.make sure it doesnt get kinked.

you plun in the 3 pin connector (tps) and just leave the other unplugged.

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