JD needle cutting off fuel at 1/2 throttle on my DRZ CV carb

I own a DRZ400S and tried using the JD jetting kit with my airbox mod and stock exhaust.

 

So I put the new 25 pilot and 150 main jets in and my bottom and top ends are  fantastic with the stock exhaust and the 3x3 airbox mod. 

 

I swapped the dynojet needle for a JD blue needle, on the suggested clip #2. But it simply cuts off fuel and won't rev up at 1/2-ish throttle. So I put the dynojet needle back in on clip #4 as per Dynojet's manual and it runs better, but it feels very lean in the mid range (gets very noisy and very uncomfortable when revving, I think it's lean because the engine sounds like it's hitting the limiter at 1/2 throttle and I absolutely hate the noise.)

 

I'm at 50ft above sea level, anybody have any ideas? I want to try the JD needles but don't want to take the carb out a million times tuning it, so I was thinking I'd put the Dynojet needle on clip #5 to try and richen up my mid range. But then again maybe I'm completely wrong.

I own a DRZ400S and tried using the JD jetting kit with my airbox mod and stock exhaust.

 

So I put the new 25 pilot and 150 main jets in and my bottom and top ends are  fantastic with the stock exhaust and the 3x3 airbox mod. 

 

I swapped the dynojet needle for a JD blue needle, on the suggested clip #2. But it simply cuts off fuel and won't rev up at 1/2-ish throttle. So I put the dynojet needle back in on clip #4 as per Dynojet's manual and it runs better, but it feels very lean in the mid range (gets very noisy and very uncomfortable when revving, I think it's lean because the engine sounds like it's hitting the limiter at 1/2 throttle and I absolutely hate the noise.)

 

I'm at 50ft above sea level, anybody have any ideas? I want to try the JD needles but don't want to take the carb out a million times tuning it, so I was thinking I'd put the Dynojet needle on clip #5 to try and richen up my mid range. But then again maybe I'm completely wrong.

Have you tried adjusting the needles. I would take the adjustment to the top and bottom positions to determine if you are in fact rich or lean.

Get a caliper (harbor freight) and measure the width of the needles, so you can see if you are going lean or rich with your problem.

Probably lean.

 

JD sells only two needles.

 

Keihin sells over 35 different needles for that carb

 

Don't mix Dyno jet and JD jet brass in the same carb. 

Dyno jet jets are not flow tested, and are inconsistent.

 

You should  be posting this in the DRZ forum where the knowledge is deeper


I just re read your post...' sounds like it 's hitting the rev limiter'....that is 'rich blubber', and the needle is too rich.

Its a hollow sound around 7k rpm. Its high pitched and hurts my ears. Doesent pull well when the noise happens. Basically high pitched note instead of braap in the midrange.

If the motor goes dead, like a kill button, that is lean

If the motor sutters, that is rich

 

I would put in a new plug and check your plug wire first

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