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is this jetting correct?

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carb is from carbpartswarehouse and since I just put on rs3 exhaust I thought I would ckeck and see what jetting they used.bike is a drz400s stock except for the exhaust. Elevation is 500 ft roughly.

ocemm needle clip 4

fuel screw 2 tuns out

main jet 160

pilot jet 38

main air jet 200

pilot air screw 1 turn out

runs pretty good but it seemed like it started hesitating when it warmed up at mid to wot like it was running out of gas. never did that till I put on the rs3

any help would be aprreciated.

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I searched through all the jetting info an d the only thing in question is the 38 pilot and the emm needle I quess.

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Needle is correct, though you may want to try clip #3.

Main may be large, pilot is small (You did take out the #100 slow air jet from the carb bell, right?), you need to do the tests to confirm.

When you saw pilot air jet, you mean the fuel screw on the bottom of the carb, right?

Fuel Screw/Pilot Jet

Fuel screw settings in the 'book' are recommended starting points. Every bike is different, as is the temp and altitude. Set the screw according to this method.

Gently turn the screw all the way in. Now back it out two turns. Start the bike and fully warm it up, go for a 10 minute ride. Set the idle to speed to 1,500~1,800 RPM as best you can (I know, without a tach this is tough, just set it to were it idles relatively smoothly). Once warmed, slow the idle to the lowest possible speed.

*** When turning the fuel screw, keep an accurate 'count' of the amount you are turning it and record it in case you have to reset it for some reason. Makes life easier when you can just set it from notes Vs. going through the procedure again.***

Turn the screw in until the idle becomes rough or the bike stalls.

if it stalled, open the screw about 1/4 more turn. Restart it and slowly screw it in till you can just perceive a change.

If the screw can be turned all the way in and the bike still idles perfectly and does not stall, then you need to go down a size in pilot jet.

Now very slowly, open the fuel screw till the idle is smooth. Blip the throttle, let the bike return to an idle, wait say ten seconds. Confirm it is the same smooth idle.

If the screw has to be opened more than 3 turns to get a smooth idle, you need to go up a size in pilot jet.

If you find it does not stall with the larger jet but has to be open more than three turns with the smaller pilot jet, put the larger one in and set the fuel screw at 1/2 turn.

If the idle speed increased, adjust the idle speed knob to return the bike to a real slow idle speed. You must then re-visit the fuel screw. Keep doing this till the fuel screw is opened just enough to provide a nice steady idle at the lowest possible RPM. Once this is done, increase the idle speed to the normal one for your bike, typically about 1,500 rpm, but go by the spec in your manual.

Main Jet

Starting with the recommended main, remove the airbox door and go for a ride (bike fully warmed up). Is it better or worse?

If it is better, you need a smaller main.

Go down one size, replace the airbox door, ride. Remove the airbox door and test again. Better or worse? If better, go down a size again. Keep repeating this till the test with the airbox door is worse.

If it was worse with the airbox door removed, tape over 1/3 of your 3X3, test.

If it is worse now with the tape and was worse with the airbox door off, your main is just right. You are done!

If it seems better, you need to go up a size in main jet. Test it again (remove the tape). Replace the tape, test again. If with the tape on it is better, go up another size in main. Keep repeating this till having the tape on is worse than with it off.

To finish up and ensure you are set accurately, retest the bike with the tape off, ride it, then remove the airbox door. Best performance should be with the airbox untapped, airbox door on.

Remember, the main only operates at WOT. Ideally, you want to be in 3rd of 4th gear doing the tests, hitting max revs (just shy of the limiter) for at least 10 seconds to get an accurate representation of the jet status.

Be sure to keep notes of your settings. You may find you need to make a change, say if you're riding in the mountains or down at the beach. Returning home, it is a simple matter of referring to your notes to restore things.

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sorry,pilot air screw old style fcr. seemed a little better with airbox lid off and the insert in the rs3 but still does not seem to rev out and the more load on the engine the worse it is.

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seems better at clip 3 but still bogs at wot and only in gears 3rd through 5th. I did notice the pump squirt seems weak at first then shoots a steady stream. At first it dribbles out.

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the bike ran fine before the rs3 and the rs3 has the insert in it I was under the impression it would be about the same.could the rs3 cause it to need a 155 main instead of the 160.

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