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Drz will not idle!!!!!!!

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My bike will not idle.

I had a slant 39mm fcr on it. tried everything. here is the link to the thread.


i just got a 41mm fcr-mx off of a ktm 450 sx

BIKE IS DOING THE EXACT SAME THING!!!!!!!!!!!!!!!!!!!!!!!!

i cannot get it to idle or run down low for the life of me. I am seriously considering setting the bike on fire.

I have never been so frustrated in my life

my jetting is

175 main

48 pilot

100 pilot air

stock KTM needle 3rd clip. ( I have an EMN needle that im gonna throw in later)

Please someone help me. I will ship the carb to someone if they want to take a look at it for me.

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yes the square plate is down.

I will make sure I get the EMN.

I have an EMM in my box of jets, is that richer or leaner than the EMN?

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I canabalized my slant 39mm fcr for its slide plate gasket.

The idle has gotten better, it will now idle for a few seconds before dying (5-10) seconds.

Also the idle doesnt "hang" like it used to.

The slide does have some wear on it up at the top and the plate has wear on it toward the bottom. I can wiggle the slide inside of the carb body a little bit. Is this ok?

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so i just called sudco and ordered another slide seal

the guy that i spoke to told me that the slide seal is the most important part of the carb.

he felt confident that the issues that I am having are slide seal related. Apparently these little seals need to be replaced every couple of years.

20 bucks for a new piece of rubber.... I really hope this fixes it!!!!

I w

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so after more research i found that Honda sells the entire carb plate with the rubber gasket for 57.83 in the TT store.

This is the part number from Honda

16037-meb-671 Honda VALVE SET, FLOATING

I am going to order this as well as i have read a ton about these carbs and apparently some people replace this part every 25hrs.

I will keep updating this thread with my findings, I want this to be a resource for others with the same problem.

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I've been reading these posts because the motor has been acting up for me as well (with a really new TT store FCRMX39), so I am starting to think that the motor has an issue or the cams are causing an issue.

I found two major issues with your set up:

1. the slide plate on the FCR carb you had instealled was shutting completely when you let off the throttle. I replaced the carb with a new one so that isn't an issue anymore.

2. The clearances on the intake valve were at 0.04mm and less than 0.04mm. I shimmed the valves so that they are back in spec.

Now that both of those issues are addressed, the bike still wont idle correctly. I am able to get the bike running, but it idles really high, then dies shortly after. The automatic decompression mechanism has been removed from the exhaust cam, but I am not sure if this is enough to cause the poor idle.

One other thing that concerns me is that when I got the bike from you, the exhaust header was not firmly mounted. It was actually wiggling around and the exhaust port was exposed to outside air.

I am hoping that the motor is just acting funky because of jetting, but I can't even get it to idle normally with eddie's recommended jetting. And furthermore, the FCR39 carb you had installed was running -

160 MJ

45 PJ

EMM Clip 4

#100 PAJ

Fuel mixture screw w/ no o-ring (not sure if that makes a big difference, but I know it should have an o-ring)

Eddie recommended:

158 MJ

45 PJ

EMP Clip 3

PAJ removed

Fuel mixture screw around 2.25 turns.

The bike idles much better with the #100 PAJ installed (unlike Eddie's recommendation) and I am not sure why. To me it seems like it runs too lean with the #100 PAJ removed... I say that because the header was glowing red when I ran it that way and the bike would rev really really high when I started it.

Do you mind answering these questions?

1. Was the bike ever idling correctly at any point in time?

2. Did you change the jetting when you were running the high octane fuel?

3. You had a thread talking about how you were riding the bike a lot at the track, how was it running then?

I need to figure out how to get this motor running correctly because it was supposed to be my daily driver. I have put a lot of time into this bike and a bit of money buying tools to fix it, and I am not seeing much progress. Any help and extra info would be greatly appreciated.

And please keep me posted on the registration issues we talked about today (keep me informed via phone). Thanks.

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