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Jetting DRZ400k4

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I know, I know... There are already a million threads specifically for this issue, and I've read about a dozen of them in the last 10 minutes.

My request is this.

I need a jetting chart, with elevation and temp recommendations.

I can't seem to find anything that will tell me where to even start with jetting my FCR39 according to my altitude and riding temperature.

I ride between 6000' and 8000' in SW Montana, so 50° - 75°. It currently has what I believe to be stock jets already.

As far as I'm aware, everything on my bike is stock except for the White Brothers E-Series exhaust.

Advice from my previous post leads me to believe that this is my issue with starting when the bike is warm.

Any help is appreciated.

Thanks

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I would use the stock OBDXP needle clip 4 and  a 145 main jet for quoted riding elevation..Airbox snorkel removed... higher than that re insert the snorkel for easy fix

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9 hours ago, Craigo said:

I would use the stock OBDXP needle clip 4 and  a 145 main jet for quoted riding elevation..Airbox snorkel removed... higher than that re insert the snorkel for easy fix

Now it's time to show my ignorance for mechanics... What is the airbox snorkel?

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6 hours ago, kodiak2010 said:

Now it's time to show my ignorance for mechanics... What is the airbox snorkel?

I believe he means the 3x3 mod.

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4 hours ago, zDirtyDeedz said:

I believe he means the 3x3 mod.

So, it looks to me that the 3x3 was cut from the previous owner, but I don't believe it was re-jetted afterwards. So swapping to a 145 main jet would be a good place to start and see what happens?

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2 hours ago, ohiodrz400sm said:

The E model doesn't need the 3x3 unless it is the California E33 or later models with the CV carb(I think)

Sent from my XT1650 using ThumperTalk mobile app
 

Mine is a kick only model with the FCR39 if that makes a difference?

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2 hours ago, ohiodrz400sm said:

The E model doesn't need the 3x3 unless it is the California E33 or later models with the CV carb(I think)

Sent from my XT1650 using ThumperTalk mobile app
 

I was under the impression all DRZs were severely deprived of air from factory and that the 3x3 would help all, but I own an S so what do I know lol

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13 hours ago, zDirtyDeedz said:

I was under the impression all DRZs were severely deprived of air from factory and that the 3x3 would help all, but I own an S so what do I know lol

 

Kicker models and FCR equipped E models have a 3"x3" hole in the top of the air box (with snorkel removed) straight from the factory. That's where the "3x3" part of the 3x3 mod comes from - it is so the air box opening is the same across all model DR-Z400.

The mod accomplishes (2) things: 1) it opens the air box for more air, and 2) it standardizes the air box opening so jetting information can be shared with some accuracy.

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47 minutes ago, 38super said:

According to this chart, the closest to my setup is the 00 Y, which is a 162 main, 45 pilot, 5th position. My carb is currently set at a 138 main, 65 pilot, 4th position.

The information I've been getting has been all over the map and I'm really confused.

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Look at lines 5 & 6.  Bracket the MJ from 142 to 152, match pilot , air jets and needle.  Consider purchasing the R&D flex jet and Boyeson quick shot for easier fine tuning.  Jets R Us is a good source for jets and needles. 

162 MJ is normal for sea level.  4000' altitude is a drastic air density change compared to sea level, you're above that so jetting will be more linear.  You will have to experiment to find the best jetting combination for your riding.

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According to this chart, the closest to my setup is the 00 Y, which is a 162 main, 45 pilot, 5th position. My carb is currently set at a 138 main, 65 pilot, 4th position.
The information I've been getting has been all over the map and I'm really confused.
Jetting is a trial and error thing. You're not going to find a difinitive answer in a chart.

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On 8/12/2017 at 7:12 PM, 38super said:

Betty Crocker doesn't ride dirt bikes.

Well she should.

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