Drz idle problem

I have just recently put an fcr, rs2 and 3x3 on my 2009 drz 400 sm.

After some initial dramas the bike now seems to be running fairly well bar for a slight idle issue.

When cold and with the choke out the bike idles at warm speed, not slightly higher as you would expect when the choke is on. When you give it a slight rev it then settles on the higher choked revs.

When riding it has a very slight surge issue, kind of like it running out of fuel. Only very slight though, it also lets out the odd back fire whilst cruising too, just small ones.

Then when you pull up at the lights it sounds like it's about to stall. Give it a slight rev and it comes good.

Any ideas friends?

what is the current jetting? does the idle react to fuel screw adjustments properly? did you get the correct air boot adapter?

- 200 Main Air Jet

- 160 Main Jet

- 45 Pilot Jet

- 100 Pilot Air Jet

- EMN needle

2.5 turns fuel screw

Yes I did get all the correct parts. It 90% solved the problem so I didn't bother pulling the carb apart. The idle screw does make a difference but you need to put a full turn or two on it to make a difference.

I have not touched the fuel screw yet. I set it at 2.5 turns before I put it in and have not changed it, awaiting educated advise.

with the fuel screw fully closed does the bike still idle?

Haven't tried anything with the fuel screw yet.

What does it mean if it still idles with the fuel screw in?

would mean the pilot circuit is too rich.

What would be the fix for that?

If it doesn't idle with the screw in what could the problem be, and it's solution?

I will play with the screw over the weekend


I didnt get to play with the fuel screw over the weekend but I decided to bite the bullet and pull this mongrel of a thing out once more this coming weekend. This time i want it to be the last time.

So while it is out this weekend i want to give it an bit of an overhaul and check everything over.

I ordered some new jets, since i dont know what is in it or the condition of the parts.

I just want to know what else those more knowledgible than i recommend i check while its out and any settings those parts should be at.

Should i be tinkering with things like the acc pump?

You tell me guys, what should i go over?


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