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jetting basics - ignorance is bliss or....

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Hi there thumpers.

Here`s the problem:

1) I´m a newbie at this

2) I´ve just received a jetting kit. JD.

3) I´ve got a 2001 DRZ-S bored to 440 wich hopefully should work now after a year of trouble and incompetent mechanics.

4) I´ve done the 3x3 airbox massacre

5) I´ve got a "faxtory" jetting kit innstalled wich is not set up for the 440 kit.

Is there a basic setup I can try just so I can be sure the bike will fire up and work?

If it mathers: I´m living in Norway, by the coast. low altitude.

6) I know theres been a million pluss post about this. Its a lot to sort through and hard to find exactly what I want. Is there a website that summarises the best options or something?

Ps. sorry if my english is bad. I usually write in norwegian :naughty:

Chartan

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1) I´m a newbie at this-- OK

2) I´ve just received a jetting kit. JD.--??? JD (James Dean) kit is for the "E" FCR carb. Is that what you have? Or do you mean DJ (DynoJet) for the "S" CV carb?

3) I´ve got a 2001 DRZ-S bored to 440 wich hopefully should work now after a year of trouble and incompetent mechanics.---- OK

4) I´ve done the 3x3 airbox massacre---OK

5) I´ve got a "factory" jetting kit installed which is not set up for the 440 kit.---OK, but it will work if it was working before.

Is there a basic setup I can try just so I can be sure the bike will fire up and work?---- Yes. Go with what you have. It would help if you posted the specific tuning parts. "Factory kit" does not mean much. Need to know for sure what carb you have to recommend JD or DJ kit parts.

If it mathers: I´m living in Norway, by the coast. low altitude. ---OK

6) I know theres been a million pluss post about this. Its a lot to sort through and hard to find exactly what I want. Is there a website that summarizes the best options or something?--- I don't know.

Ps. sorry if my english is bad. I usually write in Norwegian--- Better than some english speakers.

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2) I´ve just received a jetting kit. JD.--??? JD (James Dean) kit is for the "E" FCR carb. Is that what you have? Or do you mean DJ (DynoJet) for the "S" CV carb?

K&N Dynojet for the Mikuni. Sorry 'bout that.

Anyway, I've jused the parts from the kit. And it runs ok at low to mid rpm at least. But then it stops. I'm guessing the main jet is to small?

5) I´ve got a "factory" jetting kit installed which is not set up for the 440 kit.---OK, but it will work if it was working before.

It wasn't broke, but I fixed it anyway.

>Is there a basic setup I can try just so I can be sure the bike will fire up >and work?---- Yes. Go with what you have. It would help if you posted >the specific tuning parts. "Factory kit" does not mean much. Need to know >for sure what carb you have to recommend JD or DJ kit parts.

Its a Mikuni. I'm guessing I shold at least move up to a 150 or larger main jet?

- Chartan -

2001 DRZ440S

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Also, what kind of exhaust head pipe do you have on that DRZ? The factory "S" header or aftermarket?

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I've got the stock exhaust.

The big bore kit is Wiseco with the E cillinder foot gasket and a 13.5-1 compression. So far I've been using 100 octane gas.

The main jet now is 136.

- Chartan -

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would it help (short term) to go back to the 142.5 stock main jet?

Anyway, thought I could give a litle update on what's been happening to my engine.

It was bored last june, then I ran it for about 2000 km before it sounded so strange it was brought back to the dealer. They couldn't figure it out. Then I brought the cylinder to the shop that had fitted the wiseco kit, and they found out it was oval(!). Then it was rebored and refitted with a new wiseco sleeve. The dealer then put it together (sounds easy? the process took 5 months!).

Then I drove the bike home, and it started sounding strange again. The pipe glowed a minute after starting.

At that point I was ready to give up the entire project.

But in January I plucked out the engine, put it in a crate, and sent it the 8 hour drive to Norways only suzuki motocross dealer.

Turned out my local dealer had assembled the engine with the S foot gasket and standard top gasket. How could they not understand that the top gasket for a 400 doesn't fit a 440?

Anyway, I now have the engine back in the bike with the correct E foot gasket for my 440 wiseco kit and a wiseco top gasket.

The thing sounds a whole lot better. Hopefully I can sort out the jetting and run it in nicely. I want to ride the damn thing. It's already cost me too much money and way too much time! :naughty:

- Chartan -

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Yes you can use the stock 142.5 main jet, but I suspect burned (as usual) is closer to correct recommending the 140. The 142.5 will not cause problems. If you are that close, it will be just a little fat (sluggish) on top. At this point, you really need the Keihin FCR carb to take advantage of your other engine mods. Do not mistake the rev limiter for a jetting problem. Once you hit the limiter it will always run like crap.

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