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Jetting - Confused

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I have a athena big bore ,full rs-3,fcr mx(TT kit), 3x3 mod,ext. fuel-screw(Kientech)

Been readin jettingposts whole day ,but gets confused by different opinions

Here's the adwise I got about jetting from Eddie:worthy: :

158 main jet

200 main air jet

EMN needle

clip 3

45 pilot jet

pilot air jet removed

2 turns fuel screw

o-ring mod.

I've got my jd-kit today,and they suggest blue needle #3 clip and 165 mj.

TT shop suggested Blue needle(Norway) 3 clip

165 mj and 1-1 1/4 turns on the fms.

Some also adwise to go down on the pilot jet when applying ex. fuel screw

What do you suggest will be the best (It wasen't a 158 mj in the kit...),so I'm stuck with 155,160,162,165 mJ

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Follow Eddie's advice. I cannot state that strongly enough.

Not having a 158, run the 160 and do the main jet test.

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 or 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.

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Tanx a lot :D:)

Very good adwise ; why isn't this in the faq???

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my suggestion is using the EMN needle.

if you are using the jd kit,the setting they give is good.

You're the boss , I'll stick with the EMN needle :)

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Is the JD Jet kit intended for the FCR MX carb? The last time I talked to James Dean he only had a kit for the DRZ OEM FCR? There are enough differences in the OEM style vs the MX style that the jetting is not completely interchangeable. Eddie's advise is always good. If you try the JD Jet kit go with the advise that goes with the JD kit parts.

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Thanks for helping:applause:

I've decided to follow Eddies adwise, and ordered a bunch of jets from tt-shop(and a lot of other stuff...).

The bike runs ok for now with the 160 mj ,but struggles with coming down to idle when riding. Could be wrong position on fuelscrew(Haven't got my ext. in yet),or something else,so I'll just have to wait for the parcel to arrive.

Last time I ordered from TT-Shop, it took only 6 days incl. weekend to get the goods(To Norway),so I'll be going for rejetting and finetuning next week.

Thanx again for good answers and help:applause:

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My new jets arrived from TT-Shop today ,together with the genius jet-tools:applause:

Changed my main jet from 160 to 158,as Eddie adwised, and I can't belive that a so small change in jet-size should give so much difference.👍

The bike is now jetted as Eddie suggested, and runs better in all parts of the register.

Eddie: Thanx a lot ,you are absolutly the king of jetting:worthy:

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