DRZ 400s with FCR39

My DRZ400S have FCR 39 slant body and a complete exhaust from a DRZ400E with this jetting

160 main jet

48 pilot jet

stock DXP needle clip 4

2 turn fuel screw

This bike works good with this set-up

I make yesterday 2 others mods

1- DRZ400E cams

2- FCR 39 jetting whit TT set up

155 main jet

45 pilot jet

200 main air jet

100 pilot air jet

EMN needle clip 3

2 1/4 turn fuel screw

and i remove the coast enrichener

Whit this set-up the bike runs but it is less powerfull than my first mods (6-8 mph moore and better throttle response without E cams and my first jetting)

I rechek my cams timing and it's at the right place

What i do wrong with my jetting :smirk:

it's not the good jetting for my set-up ???

Give me answer to make me out of trouble

THANKS Pat

I added E cams last week to my drz400s with the E header also (I also have a FCR-MX). I didn't notice much of a difference. I'm wondering if the E cams would like higher compression. Would higher compression move more air?

The cams don't change compression ratio.I don't know the specs difference for the DRZ E and S cams but normaly a more performant cams give greater valve lift and duration opening

What's your FCR-MX jetting ?

I ride at sea level to 1500ft

The cams don't change compression ratio.

but they do change the dynamic compression and affect cylinder pressure.

post a picture of the cam timing from the sprocket end with the tdc mark lined up in the window.

what year E cams ? ie what letter is stamped on the sprockets. later year E cams are in fact S cams

The cams is from a 2001 DRZ E sold in Canada ,not a Californian one. My S cams and supposed E cams are marqued with 29F (all 4 ) I remove the E cams and have about .025-30 " more in lift than the S cams.

Eddie, i have anything to take a picture to show you . When i buy the bike at 2800 milles from a 60 years men , now at 3050milles.

Whit the TDC mark line up the ex cams arrow 2 are perfectly up and the int arrow 3 is verry slightly backward .When i change the cams i mark the chain link in front of his arrow.

I'm sure the cams are at the good place.

My whinters 2001 DRZ 400 E When i put a MCCT and adjust valves after winther the cams timing is not as good of my 400 S ( a new chain needed ) and it runs better than my 400 S Whit cams and jetting

My jetting written earlyer is good for my aplication ???

or some mods are needed ???

marking the chain does no good. the chain can move off the teeth of the lower sprocket.

the jetting is reasonable.

You are wright for marking the chain, but after chain + MCCT and turn engine 2 time to return next TDC and rechek the mark and it is OK .

Q for jetting. The need of the 100 pilot air jet it's only for the CE removal ???

this mod lean the air/fuel mixture ???

The pilot air jet is for the air/fuel mixture for ( only ) the pilot Jet ???

The CE is only for backfire in engine deceleration ???

I verify the color of my plugs and the mix is lean ( on normal riding )

what's the best for me

1- pilot jet 48 , 1 turn fuel screw , 160 main jet

2- EMN needle clip 4

3- reinstal the CE

4- or ?????

Thanks Pat

You can't tell lean/rich by looking at the plug with modern fuels run in the DRZ.

I added E cams last week to my drz400s with the E header also (I also have a FCR-MX). I didn't notice much of a difference. I'm wondering if the E cams would like higher compression. Would higher compression move more air?

I have now changed to a 160 main Jet. Didn't think I'd need it because I still have the stock exhaust with the spark arrestor removed. On the freeway with the 155 my bike would hesitate when I opened the throttle, better with the 158. Now the hesitation is gone and I feel like I have more power. Yesterday I speed tested my bike because it was 103 degrees outside. I figured if its jetted to rich, it will run like crap. It ran the best it ever has.

I was wondering if you have discovered any solutions? I still can't believe my bike needs a 160, and maybe I'll try a 162.

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