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how much bottom end torque?

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so i am getting some time on my new 05 yz 250 as the weather gets nice. previous bike was an 07 yz250f. i have been playing with the pilot jet/needle and seem to have it pretty crisp on bottom. it has 15 52 gearing. i am able to pull second gear from almost a stand still 90 degree corner with just a slight lug before it hits the pipe. if i don't roll onto the throttle and jsut rip it open it will lug for a second before it screams..doesn't feel like a bog.... it feels to have about the same low rpm torque as my 250f, does this sound right? it is stock with an 07 pipe with r304 shorty silencer. just curious how to get more low end torque if this is about right for my stock pipe and r304 shorty silencer. i feel confident the jetting is pretty good. also have the timing 2 degrees retarded.... thanks for any insight!

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I've ridden several 250Fs and properly setup the YZ250 has more bottom end power.

1. 15 52 gearing will lug the motor a little more than stock 14/50.

2. How is your compression? How old is top end?

3. What is your current jetting?

4. Retarding the timing may have cost you a bit of that bottom end "hit", but it shouldn't have been much.

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the bike has about 30 or so hours on it stock top end. looks like new. compression was 230 but my gauge reads a little high, probly more like 200 or 210. leak test was also good.... jetting is 45 pilot 1 turn on the air screw, n3cj needle 2nd clip and 178 main. temp is about 70 and humid at sea level. i know the main is fat, but it is going to be 40 tomorrow, so until it stays steady warmer temps i was going to leave it.this way i can turn the air screw and change needles for the colder temps.. i figured the main does not have that much effect on the bottom 1/4 throttle. oh, amsoil 30 to 1 premix with real 93 octane gas. i know the gearing is a little tall but i was wondering if it should still pull similar to a 250 4t. i had 14/52 gearing but that was a little too low. it did pull harder off the bottom though. made first gear not really usable for my type of riding. the bike came with 13/52! seemed really low to me.... brand new renthal rear sprocket so i was trying to make it work:) i think stock gering would be about right.

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Lower the clip one on your needle. Might need a 48 pilot too. Your exahust combo should make the bike want to pull out from underneath you. 👍

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ah, you think it is a little lean for 70 degrees? with the 50 pilot 2.5 turns out the bottom was mushy at 75 degrees. the n3ew needle feels good up till about 75 degrees then the mid feels mushy to me. that was with a 50 pilot also...today the mid felt pretty crisp with the n3cj.......i think the n3ej may be a good needle....maybe i will try a 48 pilot next.. not sure i want to richen the midrange one clip . it is tough right now the temps are always changing....i thought the jetting was good today, maybe it was lean...all the black inside the tip of the silencer is gone but there was spooge coming out of the seal for the silencer and pipe...maybe residual from last ride.....the idle was kind of hanging now that i think back, unless i turned it way down, you might be right about the pilot.... oh, the bike does pull out from under me when it is past 1/4 throttle... almost literally if i am not careful 👍 not sure how much pull these things have just off idle....

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so it is supposed to be 50 to 60 here for the next week. i didn't want to make another jetting thread, but, i am going to try the 45 pilot with the n3ew needle and see how that feels at 60 degrees. the n3ew needle will aso richen the pilot slightly correct?

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so it is supposed to be 50 to 60 here for the next week. i didn't want to make another jetting thread, but, i am going to try the 45 pilot with the n3ew needle and see how that feels at 60 degrees. the n3ew needle will aso richen the pilot slightly correct?

Yes, and from my experience that needle is pig rich for slow speed trail riding. N3EJ mo better. I used the N3EJ in the winter and CJ in the summer.

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it sounds like you're way lean on that pilot.

i have a 50 in mine, 178 main, 2nd needle position. (im in ny too)

whats your plug look like?

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This is what I use for racing/riding in NY , and it works great for me. N3EW top clip, 48 pilot, 178 main, 2 turns out on the air screw. That will get you damn close for our riding conditions for this time of year. Put the timing back to the stock marks.

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the plug looked good actually, dark tan looking, maybe a little rich. i like the timing 2 degrees off to get the more linear power for now. i agree the n3ew is rich, it seems ok for around 60 degrees though on the second clip. i am not sure how to tell if the mid is lean, so i am being cautious. i realized i had the n3ej, not cj in yesterday. it felt lean to me, how cold did you run the ej needle in shrubit? i want the pilot circuit really crisp since i tend to go back and forth from lugging to mid range as i ride instead of changing gears. maybe i will try the 48 pilot also. thanks for the tips. my problem seems that if the mid range is nice and crisp(n3ej) the pilot circuit feels off. then i feel the mid is lean... with the n3ew needle, the pilot circuit feels better but i know it is rich in the mid. hence, the lean pilot jet.... i had the air screw at 1 turn, so it might be close to a 48 at 2 turns? thanks again, i will get out tomorrow with the n3ew and 45 pilot in 50 degrees to see how it feels....

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Have run the N3EJ down to about 35*. Round about 60* is when I switch to the N3CJ.

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IMO, the 45 pilot is too lean, especially @50 degrees. Your problem is you're running into a compromise, being strong lowend = timing back to stock, or smoother power= timing retarded. I run my bike with an 11oz ffw an the timing at the stock setting for the best of both worlds. I race the bike in the woods, so I know all about having to have smooth tractable power, but yet have strong lowend.

I also race a 09' CRF 250 and that bike feels as though it has just as much lowend as my 07'yz 250. I may even use the clutch less on the 4 stroke than I do on the yz. The yz is much quicker from the upper midrange through topend.

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IMO, the 45 pilot is too lean, especially @50 degrees. Your problem is you're running into a compromise, being strong lowend = timing back to stock, or smoother power= timing retarded. I run my bike with an 11oz ffw an the timing at the stock setting for the best of both worlds. I race the bike in the woods, so I know all about having to have smooth tractable power, but yet have strong lowend.

I also race a 09' CRF 250 and that bike feels as though it has just as much lowend as my 07'yz 250. I may even use the clutch less on the 4 stroke than I do on the yz. The yz is much quicker from the upper midrange through topend.

Fully agree with all 'dat. I run a 50 PJ in the winter and a 48 all else. Timing is stock.

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ok, you convinced me..48 pilot jet it is...i did not think the timing change would take from the bottom end....after i try the 48 pilot and ride it i will ponder putting the timing back... thanks for the insight! i think i will stick with the n3ew until it gets up to 70 or so. 48 pilot 2 turns out, n3ew 2nd clip and 178 main until it gets warmer 👍

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Try the clip in the top position also, it leans the bike out in the middle and makes the throttle response just a little crisper. Let us know what you think of the changes.

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top position even at 50 degrees?

No problem on a N3EW. That needle wasn't stock until 2007 anyway. N3EJ preceded it as the stock needle.

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Yes, even at 50 deg.

I believe the n3ej needle is 1/2 clip position leaner than the n3ew at all clip positions,and that's the only difference.

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ok, so i looked in the manual about this needle stuff. the n3ew is the same taper as the n3ej but has a richer straight portion. this effects 1/8 to 1/4 throttle only, then the needles are the same. the n3ew on clip 1 is richer till 1/4 throttle then the n3ej clip 2, but then leaner by one clip position over the n3ej once you are into the taper. i bet this produces a ton of mid pull from 1/4 throttle up? considering it is on the first clip, more straight portion is being used, delaying when the taper comes into play, delaying the mid hit also? i decided to just change one thing at a time for now. last ride was 45 pilot and 3ej needle on 2nd clip. i am going to try 48 pilot, same needle 2nd clip to see if it makes a difference. after i am happy with the pilot then i might try the ew needle on the 1st clip.... i am gettng the idea of the needles, last letter is the diameter of the straight portion( 1/8 to 1/4 throttle) the first letter is a change in the taper, which is basically a .5 clip position change. n3ej on 2nd clip is .5 richer then n3cj on 2nd clip....lots of choices in tuning the needle 👍 it seems you can manipulate when the taper comes into play and how rich it is before the taper......i wish needles were as cheap as pilot jets🤣 will post up later tomorrow.

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