EMM vs DTM - WR vs YZ timing



It's good to see your jetting results are coming together. It makes posting here on Thumpertalk more worthwhile, primarily due to the efforts of Taffy providing suggestions and guidance. Looks Good!


Seems we all tend to the same settings :)



PJ 35

PAJ 55


Feul srew 1 1/2

EMM #4

APJ you can't really call it a squirt

Great power in low revs, kind of a kick the ass type power delivery (but controlable, great for wheelies) from midrange to top.

Very crispy in low revs but A little bog is subsiting in the very low revs, only have to shoke for a few seconds when cold starting, so I'll try to close and open the PAS to check and try clip#4.


when i went from 65 to 60 starter jet mine was happy to sit on choke whilst i put my helmet and gloves on. no 8-stroking.

so MUST it have the choke off because it would stall or is it because you can?

you may need to drop your needle to lean it?

you may need to lower your PAJ to 45 as there is a low speed shudder if the PAJ is too open.

however the bog will be a rich setting so lower the needle first.

the settings in europe are VERY similar but those in the states are ok at sea level but that now appears to bew only 50% of them. altitude setting without having been there is difficult but worthwhile.



I can put the choke off because I can, not because it will stall.

In fact my actual clip pos is #5.

At one side you advise me to richen the PC by closing the PAS to 45 and at the other side to lower the needle to lean out the transition from PC to 'Needle circuit'.

Well, let's just try it. Guess this is the best training to get some carb tune feeling.

Thanks. :)

i only say it like that because you must have the results of what the needle does before you do the PC! that's the only reason.


I got my EKN needle in and here are some results:

Test 1



Needle-EMM c#4 > EKN c#4


PA(J) Screw-45 (1/4 turn out)


PS-1 > 1.5


This did not run good from 0 to 3/8 throttle, felt like misfires. I know that the EKN is 1 clip richer but thought maybe a little more midrange.

Test 2



Needle-EKN c#4


PA(J) Screw-45 (1/4 turn out) > 60 (3/8 turn out)

PJ-35 > 38

PS-1.5 > .5


This ran slightly better than the original EMM setup in Test 1, 0 to 1/4 throttle, but idle (tickover for you Taffy) is rich. The mid range did seem stronger, but I didn't test it much. I'm thinking the 0 to 1/4 trottle was actually lean when I thought rich.

My thoughts are the EKN c4 w/38PJ-60PAJ(S) gave me better 1/8 to 1/4 because of the richer needle setting. The PC had to be richened to match the needle root diameter, but this is causing my rich idle (tickover). Set the idle with the root dia., right!

I am going to put the EMM back in at c#5 and put back the PJ35/PAJ(S)45. This should improve my 1/8 to 1/4 throttle without the rich idle (tickover).

One thing I had overlooked was my APJ. I thought I had .024 , but was really running .003, must have messed with it then not reset. I set to .024 and did snap wheelies, changed to .032 and they got even better, getting scary now as there was no problem will roll on wheelie or lofting the frontend for logs and such before. I will go back to zero APJ for jetting, but that was fun!!!

[ July 11, 2002: Message edited by: Littlefoot ]

a little hard to follow your words but the test does speak for itself. perhaps you need to reflect on how long the APJ had been virtually turned off because you've based some of your testing on the results after all.

the other thing is that even lifting the needle once will richen your idle and if it was rich anyway then the EKN could still be the needle for you. that root diameter will be what you need perhaps.

little things like "how little choke did i need?" etc can all help you form an opinion. infact it should be one of the figures you use. a typical example would be to go from needing choke to not (two twists of the wrist anybody?).

the other is how long before it eight-strokes.

if you do lift the needle i would try the following test and that is;

35PJ and 70PAJ. then try turning that PAJ(S)in a little at a time and you will feel what's happening and the results will virtually complete your work.


[ July 11, 2002: Message edited by: Taffy ]


Reading your post carefully, it looks like you are on track. Give the EMM#5 a try with your best PJ/PAJ setting. The EMN has the leaner straight diameter 0-1/4 and the richer taper start narrows it down less than that. Thanks for the update.


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