LT racing jet kit report...

[pobit]

Originally Posted by iancp5

Rode the bike with Pobit's jetting in an event yesterday and it was the best it's ever been but I still want a 250 thumper. There was one bit of the course where I was glad of the power (2 foot deep mud) but most of it cut up badly in the trees, was slippery and tight and a 300 2 stroke just isn't the tool. I might keep it though for when I do more open fast courses. Yesterday's event was over 90% in trees so close you often had to stop and squeeze the bars through. I'd like to try a GG 200 in an event but that's difficult to arrange. I like 2 stroke simplicity but I really struggled with the 300 towards the end of the competition - just couldn't open the throttle slow enough for my tired arms and shoulders even with a G2.

Of the three bikes listed, the 300 has the most easy to use bottom end. 200's squirt through the woods easier but they require more throttle skill than a 300 does. 250 four strokes do work well for tight and slippery conditions but they leave you wanting for more power any time the trail opens up.
If you have a DE model with the small ignition, you may want to try adding some flywheel weight to smooth out the power. Here in Minnesota where I live, it is always wet and sloppy in the spring and I run a small weight on my 300 to make slogging through slippery roots and rocks easier for long enduros. Dave

[pobit]

Originally Posted by GG27

I have just bought a new 2008 ec250. Its a fantastic bike! I have owned 3 250 exc KTMs and a YZ 250 but the suspension and handling of these GG's is just incredible.

My only complaint is the recommended factory jetting is off, being a little rich of the bottom to mid but has a strong linear pull from mid to top.

My current settings are:

PJ 40
Needle NIEF #3
MJ 180

Temp 50 to 70 F

I lowered the needle to #2 and she runs a bit crisper but still not ideal. The local agent recommends the following settings which he says works on many bikes here in Greece:

PJ 42
N1EG #3
MJ 178

I feel these settings will be really too lean. I called the Keihen agent for a CCK needle but the don't have it in stock and will not import them. Should I go to the equivalent Honda needle if available. Any suggestions?

Your not too lean. Your agents recommended setting is not much differant than your original setting. The leaner G needle diameter is offset by the richer 42 pilot. I doubt you would notice any differance in performance.
Jetting is a personal choice so you have to try a few differant settings to see what works best for you. Skill level, riding style and your riding area will dictate which jetting is correct for you. For an 08 250EC used off road for trail riding, I would try a 42 pilot CCK#3 178 main, #7 slide and compare it with a 42-45 pilot DDK#3 175 main #7 slide for sea level, 65 degrees. The CCK will be smooth on the bottom with a good upper pull. The DDK will have a harder off idle pull with a torqy mid to top pull. The DDK needle will require more throttle control at small openings and likes to be rode under a load at wider throttle openings so it is for more skilled or open riding areas. Dave

[GG27]

Originally Posted by pobit

Your not too lean. Your agents recommended setting is not much differant than your original setting. The leaner G needle diameter is offset by the richer 42 pilot. I doubt you would notice any differance in performance.
Jetting is a personal choice so you have to try a few differant settings to see what works best for you. Skill level, riding style and your riding area will dictate which jetting is correct for you. For an 08 250EC used off road for trail riding, I would try a 42 pilot CCK#3 178 main, #7 slide and compare it with a 42-45 pilot DDK#3 175 main #7 slide for sea level, 65 degrees. The CCK will be smooth on the bottom with a good upper pull. The DDK will have a harder off idle pull with a torqy mid to top pull. The DDK needle will require more throttle control at small openings and likes to be rode under a load at wider throttle openings so it is for more skilled or open riding areas. Dave

Thanks for the reply Pobit. Today I tried the following:

178 main
42 pilot
n1eg #3

The bike would stumble just before the power valve was starting to open so I lowered the needle to #2 and the stumble nearly disappeared. Weather was cold (about 45) and damp and engine was revving up too quickly.

I'll try to see if I can get the DDK or HONDA needle. On what bike was the CCK a standard nozzle?

[Eugene]

I've been on the Keihin site and cannot find the correct "reference" to the N3EG needle, they all list 3 letters as the reference after the N427-48 part number start. What would be the straight equivalent, or the closest to it on the Keihin site's number/letter scheme?

[GG27]

The equivalent OEM needle diameter number for G is 66

It is the second pair of numbers, the first pair is the Taper and the last letter is the L1 length. These are for straight single taper needles, For multi-taper needles I can not find the equivalent on the Keihin site either. Maybe Pobit can help on this one since he has a lot of knowledge on jetting.

[GMP]

N3EG or any N series is not a standard Keihin needle, is a triple taper OEM needle for Yamaha. All you will find on the Keihin site is the standard single taper needles. The JD jetting XL spreadsheet is handy for comparing various needles, except his own of course!

[Harry]

The N3EG is also a optional needle for KTM

[GG27]

Hi again Pobit.

I have been trying to set me 2008 ec250 but just can't get it right.

I have tried the HONDA needle at 3.5 clip position 42pj and 178 mj air temp around 20 to 25C and the bike would really sputter all over the midrange so I changed the needle to the original N1EG #3 42 pj and went to a 175 mj. The 1/4 to full open throttle reposnse was goog but was rich right off idle to 1/8.

It seems that this bike works better with the needle at #2. Should I try dropping the needle one clip?

Can I put the 1369D at #2 or#3 and drop the main?

I race in enduros and scrambles and I need power across the board but more in the low mid rev range. I like the motor to screem on top and lug on the bottom.

Thanksj

[gasser]

Glenn I have an 07 250 with the heavier EC ignition that runs very clean except just off the bottom from idle to 1,000 rpm. If you run it that slow on a hill it will load up and require a down shift or clutch slip to clean out. Any suggestions?
Ken

178 main
42 pilot
#7 slide
stock needle clip : #3 position(temp. 40-50 degrees)
next position leaner (51-75 degrees)
top (76 degrees and above)

[GG27]

It seems I'm in the same situation as you with the exact symptoms. I went down on the main to 175 but lost a little on the top. Maybe if you go to a 40 pilot the off idle rich spot will go away. What needle are you using?