Factory Needle/Jet Setting EC250

T

theexception_03

New member
Hi,

I have just got myself a 2005 EC250 and this is how it was set up by the previous owner

Needle N1EF clip pos #5
Main Jet #180
Pilot #38
Air Screw 3

FMF Gnarly Pipe

With this set up it was running very rich and had a massive problem in the mid range, it was like the engine was 'missing' but top end was brutal
It also leaked fuel from the carby out the overflow when idling on the side stand

..........................................................................................

So I have decided to run the factory settings

Needle N1EC clip #3
Main Jet 185
Pilot 38
Air Screw 2.5

Fuel/Oil 50:1

I have just put a new fuel intake Valve in the carby and checked the float height.
It also has a new crankcase oil seal.

Obviously I have never run the the 'stock' settings, can anyone tell me how the bike should run with factory jetting setup?

Thanks
Tim
South Australia
 
Looks like way over the top rich to me.Go back to original setting and drop the needle one clip at a time till it runs right.If still not right go to n1eg needle or suzy nedw.JD blue works good too.Heaps of info in this forum on this,ala jackobi.
 
As for the float height:
Is is still leaking on the side stand? If the needle valve replacement didn't solve the problem, you will have to adjust the float height a little.
It seems the new and old carb versions can benefit from a slight lowering of the fuel level. Just a mm or 2 at most.
 
If you do a search on the float level you will find heaps of info. When it comes to standard jetting they are thirsty and way rich!! Depending on what sort of power delivery your after will determine what needle you use. Search that aswell and you will get loads of info. You will also need to tell us where you are what elevation,temps etc
 
Clip 5 is towards the pointy end of the needle and clip 1 at the top. At clip 5 it would be so rich the bike would be flat out running. Without knowing too much about the 2005 models, I can tell you the newer ones benefit from leaner jetting. As suggested start at the bottom end work your way up.

1. Float level. http://www.gasgasrider.org/forum/showthread.php?t=11886 (This has been stickied) Note: that this is for the newer carbs but same basic principals. I think the float level on the original PWK was 16mm.

2. Needle Diameter and Pilot Jet. Needle in middle clip. Idle screw backed out so the slide is only a few mm up. Air screw at 1.5 turns and then change pilot jets until you get one that allows the bike to idle. I'd suggest starting with a W/I diameter needle. Maybe a 48/46 pilot but you may find you can come down as low as 40.

3. Needle choices. N1EI/NOZI (GG/TM. Rich off the bottom.) NEDW/NECW (Suzi needle. Smooth transition) N3EW/N3CW (Yamaha. hard transition). There are threads to read if you use the search. Start in clip 3 and change it as required.

4. Main jet. The size will vary depending on the needle and profile taper you choose. Start rich and work down as required, checking with plug chops.

In relation to what you have changed, if you went from clip 5 to 3 you have leaned the needle position. You have however gone 2 sizes richer on the needle diameter which will make the richness off idle worse. You've also gone richer on the main. Ideally you want to follow a strategy as I've posted above where you set a starting point and work on each circuit independantly until you are happy and then move on to the next. If you change all 3 at once you won't be able to know exactly what each change makes and will just be stabbing in the dark.
 
Jakobi said:
Clip 5 is towards the pointy end of the needle and clip 1 at the top. At clip 5 it would be so rich the bike would be flat out running. Without knowing too much about the 2005 models, I can tell you the newer ones benefit from leaner jetting. As suggested start at the bottom end work your way up.

1. Float level. http://www.gasgasrider.org/forum/showthread.php?t=11886 (This has been stickied) Note: that this is for the newer carbs but same basic principals. I think the float level on the original PWK was 16mm.

2. Needle Diameter and Pilot Jet. Needle in middle clip. Idle screw backed out so the slide is only a few mm up. Air screw at 1.5 turns and then change pilot jets until you get one that allows the bike to idle. I'd suggest starting with a W/I diameter needle. Maybe a 48/46 pilot but you may find you can come down as low as 40.

3. Needle choices. N1EI/NOZI (GG/TM. Rich off the bottom.) NEDW/NECW (Suzi needle. Smooth transition) N3EW/N3CW (Yamaha. hard transition). There are threads to read if you use the search. Start in clip 3 and change it as required.

4. Main jet. The size will vary depending on the needle and profile taper you choose. Start rich and work down as required, checking with plug chops.

In relation to what you have changed, if you went from clip 5 to 3 you have leaned the needle position. You have however gone 2 sizes richer on the needle diameter which will make the richness off idle worse. You've also gone richer on the main. Ideally you want to follow a strategy as I've posted above where you set a starting point and work on each circuit independantly until you are happy and then move on to the next. If you change all 3 at once you won't be able to know exactly what each change makes and will just be stabbing in the dark.
Click to expand...

Thanks for all the info, the needle clip was actually in postion 1 at the top. not postion 5 like I said (sorry)

Float is spot on at 16mm
 
nato said:
If you do a search on the float level you will find heaps of info. When it comes to standard jetting they are thirsty and way rich!! Depending on what sort of power delivery your after will determine what needle you use. Search that aswell and you will get loads of info. You will also need to tell us where you are what elevation,temps etc
Click to expand...

South Australia
Elevation 0-1000ft
temps at this time of year 10'C to 18'C (50'F to 65'F) these are averages
 
theexception_03 said:
Thanks for all the info, the needle clip was actually in postion 1 at the top. not postion 5 like I said (sorry)

Float is spot on at 16mm
Click to expand...

In my 300 I personally found the same with the stock needles. Really rich off the bottom and would rip up top. Would load up and smoke like a chimney if I wasn't hard on the throttle all the time. Ie 2 minutes of ST and it was chuggin. I needed the idle screw right in to make it idle and even then it only just did at full temp.

I'd suggest grabbing a handful of jets and a couple needles and playing to see what works best. My suggestions for starting are a NEDW and a N3EW. 40-45 pilots. 172-180 mains. I've purchased through http://www.powersportsplus.com/ before and although it often takes a week or two for them to arrive and some needles are on back order, its just as quick as trying to get them locally and a fair bit cheaper.
 
theexception_03 said:
South Australia
Elevation 0-1000ft
temps at this time of year 10'C to 18'C (50'F to 65'F) these are averages
Click to expand...

work your main done a size at a time till it revs out clean. then bump your pilot up a size or 2. i'm betting you'll end up somewhere around here:

175, #3, 42 pilot, 1.5 a/s


180/185 seems realy rich, but jetting is totally machine dependent...
 
Start out by switching out the needle - yamaha yz needle or leaner n3ew, etc. And with correct needle - pilot should be richer on the pilot (42/45/48) indicating you have good separation of the carb circuits. Back out idle screw and air screw should be at 2 turns or so and should be "effective" - e.g. you should be able to adjust it and see some effect.

With the stock n1ef needle - "you can't get there from here"...

jeff
 
Thanks to everyone for their suggestions and info, it has really helped me to make a few changes and experiment with the settings. I should get the bike back from the shop this week and will let you know what works best

Thanks again!
 
stainlesscycle said:
i have no problems with n1eg on a 300. maybe the 250 wouldn't like it. a little snappy at 0-1/4 but i kinda like it that way. teaches throttle control :p
Click to expand...

My bike will run with N1EF/N1EG as well. It just drinks alot of fuel and will load up if chugged around off idle too long. IE rainy wet days. The snap off idle comes from the rich-lean transition off the first taper into the second. It can be achieved by running a rich pilot and needle diameter with any needle in a lean position. To be honest I think the N1E/NOZ would actually do better in the 250 than the 300 as they tend to like a bit richer jetting (or thats what I have noticed with mine - Same bottom end, same trails, same conditions).
 
Jakobi said:
My bike will run with N1EF/N1EG as well. It just drinks alot of fuel and will load up if chugged around off idle too long. .
Click to expand...
i've not had a problem with it loading up and i did 2:30 today without even hitting reserve.....and there were lots of open fields where i ran outta gears... i thought for sure i'd hit reserve..
42, #2, 172, n1eg, 1.5 - it's snappy enough i gotta be careful for sure - can't really use 1st gear at all.. but it idles and doesn't stall out, so i'm happy with the jetting
 
Can't ask for much more than that Stainless. There are definately quite a few variables involved and we're often reminded what works for one doesn't always work for another. I'd have to imagine the stock jetting would be close, at least in Spain. Some people have been happy with it in their 2011 and 2012 models. Others have found better solutions.. It all comes down to trial and error, and at the end of the day the best you've had is the best you try.
 
I always put my bike on reserve at the start, don't wan't to have to reach down at a bad time IF I should run low.
 
stainlesscycle said:
i've not had a problem with it loading up and i did 2:30 today without even hitting reserve.....and there were lots of open fields where i ran outta gears... i thought for sure i'd hit reserve..
42, #2, 172, n1eg, 1.5 - it's snappy enough i gotta be careful for sure - can't really use 1st gear at all.. but it idles and doesn't stall out, so i'm happy with the jetting
Click to expand...

i failed to mention i'm running 50/50 92/112 - that may be a factor in my fuel economy and definitely in jetting/how it runs overall. so i would think ymmv..
 
GMP said:
I always put my bike on reserve at the start, don't wan't to have to reach down at a bad time IF I should run low.
Click to expand...

i've considered it, just never done it - i'd rather take the 10 seconds/pull of course to switch then be totally stranded. i think i'd be stranded either way, i stopped carrying extra fuel can completely ;) - only doing 2 hour races this year.
 
Yeah, in harescrambles why not do it? In enduros, it may give you a warning to bum gas off the next check crew to get by, plus you have a lot more time to fiddle with the petcock. Sometimes its hard to find a good place to grab my mouthpiece for a drink much less reach down for the petcock. It wouldn't matter anyway though usually, Sunday I had at least a gallon left, lots of throttle control and finesse though less wide open stuff. I'm only doing a couple enduros this year, doing more harescrambles as I seem to be doing very well in them.
 
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