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Jetting and exhaust help

By redleger,
in DRZ400/E/S/SM

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redleger

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Just found a pristine DRZ400E. Scooped it up for a good price. Came with FMF exhaust and airbox mod. Flat slide carb was what drew me to it. 

First issue is the slip on now melts the airbox above it. I have ordered some exhaust wrap and I am hoping this will fix that problem. Has anyone else seen this/ had this issue?

 

20130911_094537_zps250e5889.jpg

 

Next, looks like the PO did not jet it after installing the FMF exhaust system. Does anyone know which size jet I should order? None of the bike shops around here keep many parts in stock so I am stuck ordering everything. Because of this I do not want to order a jet kit since I only need one jet. The airbox has also been cut according to the airbox mod. 

 

Which jet size should I order to install. I also have never worked on the flatslide, only the CV carbs so where would I find a diagram telling me which jets are which. I know how to do it, I am however not all that savy so still need help on small stuff like that. 

 

Thanks in advance for any input in advance.

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DRJH1999

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Isn't that the crankcase breather? I'd say either the PO didn't line up the exhaust right or its getting way too hot from running lean.

I don't have a FCR so I got nothing for jetting advice. Search "FCR Jetting" and you should find tons of threads about it.

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  • 4 weeks later...
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redleger

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Ok got a new box on and jetting richened up. Not running too hot or melting the box. I had it too rich and blackened the spark plug. Backed off the jet one size down and raised the needle up one notch to the middle. Everything was running great last night for about ten minutes then on the return home it started backfiring on acceleration. I had been doing hard accels and decels previously trying to make sure everything was good. Why would it run well for 10 + minutes then start horribly back firing on accel? I am not new to jetting and carbs but this one is seriously making me lose hair I can't afford to lose. Accel popping usually means rich right? It happens at 1/8 - 3/4 throttle. Is that needle or jet? Any input would be appreciated.

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redleger

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Which Fcr carb ?..Is it the stock fcr or an fcrmx..?

What needle are you using?

Pretty sure its stock FCR. Stock needle possibly but PO did put in dynojets so possibly dynojet. Does have the adjustable ring. I have needle in middle after trouble shooting. I am gonna mess with it more this weekend but I really just am trying to figure out if I am rich or lean. I am guess ing lean but I am starting to think I am not as smart on jetting as I thought.

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redleger

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You need to inspect the needle and look for id markings...

Knowing what the present carb settings are is step one..

I can tell how to set it up but we need to know .....

1) current carb settings

2) riding elevation and climate

3) open or corked piped

4) any engine mods

1. Current stock jetting except dj kit. 155dj main currently installed

2. 100 meters (300) feet dry oklahoma climate

3. Fmf slip on . Not sure if weld was ground out or not.

4. Snorkel pulled and moose racing foam filter installed.

Sorry for delay but work has been crazy. Messed with it some today and still can't get it idling right. Carb placement makes fuel screw adjustment a pita. This bike has no seat time since I bought it and I am getting quite frusterated.

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Craigo

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1. Current stock jetting except dj kit. 155dj main currently installed

2. 100 meters (300) feet dry oklahoma climate

3. Fmf slip on . Not sure if weld was ground out or not.

4. Snorkel pulled and moose racing foam filter installed.

Sorry for delay but work has been crazy. Messed with it some today and still can't get it idling right. Carb placement makes fuel screw adjustment a pita. This bike has no seat time since I bought it and I am getting quite frusterated.

 

What needle...??....DJ or JD or stock OBDXP 

 

Current clip position from top...?

Edited by Craigo 485sm
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Craigo

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To be honest with you I have never used a Dynojet needle in an fcr.....

I prefer a Keihin OCEMN or JD needle

However I do know the recommended needle setting for under 3K ft is clip #5 and a 136DJ main jet...

http://www.dynojet.com/pdf/3111.pdf

 

This is how I would set up that carb...

160 main jet

OCEMN needle , clip #3

45 pilot jet

2,25 turns fuel screw

60 pilot air jet

Remove the Coast Enrichener, join the ports on the carb with a left over piece of hose,cap the port on the head...

https://www.thumpertalk.com/topic/980891-jetting-for-removal-of-coast-enrichener-drz400e/

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redleger

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To be honest with you I have never used a Dynojet needle in an fcr.....

I prefer a Keihin OCEMN or JD needle

However I do know the recommended needle setting for under 3K ft is clip #5 and a 136DJ main jet...

http://www.dynojet.com/pdf/3111.pdf

This is how I would set up that carb...

160 main jet

OCEMN needle , clip #3

45 pilot jet

2,25 turns fuel screw

60 pilot air jet

Remove the Coast Enrichener, join the ports on the carb with a left over piece of hose,cap the port on the head...

https://www.thumpertalk.com/topic/980891-jetting-for-removal-of-coast-enrichener-drz400e/

I assume you meant a 160 dynojet and not keihin jet.

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redleger

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Does the main jet look like this?...If so it should fit.......If not are you 100% it's a Keihin Fcr...(picture?)

Posted Image

OVERALL LENGTH = 16.5mm

THREAD DIAMETER = 4.9mm

The main jet is round however I am sure its an FCR carb. That is why I am asking if when you install the dynojet kit if you also replace the piece the jet screws into.
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Craigo

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Everything works great. Ended up having to go up a jet size but rode her to work this morning no issues except a small atumble at just over half throttle. Ill play with the needle later. It was cold thos morning so might have been running a bit rich.

 

What carb settings do you have atm..?....

If jetted correctly for mild conditions ,in very cold temps you would more likely to be lean than rich...

(The theory = cold air holds more oxygen, so more fuel is required..)

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