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Discussion Starter #21
The larger "38" may well have been drilled by someone being a cheapskate. The holes in the smaller jets need to be mega accurate if you are ever going to make sense out of your carb, what I mean is that if you buy a 38 and the hole in it is bigger than a 40 due to poor tolerances then that would screw up any form of comparison between them. (Drilling jets for methanol is OK apparently).
I did wonder if it had been drilled, however, the 'small' 38 is waaaaay smaller than the 40 and bearing in mind its measured in microns, I doubt I should be able to visually tell the difference between a 38 and 40, where as between the small 38 and 40 its easily visible!
 

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Get NEW original Keihin pilot jets from your dealer. Then try from there and get back to us.
 

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I’ve the Husky Te 250 2015. MJ:178. PJ:40, stock exhaust. Pv brass screw is flush with the case with green spring. Fitted are an sx head and xc cdi. Compression tested last week but with a short reach adapter - 195psi. Bikes done 2000 miles. It idles fine with no noticeable power band. Gearing 13/50. Used for trail riding. Mpg is 50+. Smooth ride. Currently on the lookout for an sx cdi - if anyone knows or can point me in the direction thanks. With regards to the cdi (correct me if I’m wrong) the three different cdi’s (enduro, xc, sx) are fixed state ignition advance/retard units.
 

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Discussion Starter #26
Right guys - update!

From the original settings when I got it - PJ 38 / MJ 175 / N2Z H Needle / 2nd Clip wouldn't idle and felt rough on light throttle.

Changed now to PJ 40 / MJ 172 / N2Z W needle / 3rd clip as per suggestions from these guys -https://twostrokeperformance.com.au/husky/ idles now but still rough as a badger on light throttle. Again, still ok when you wind the throttle on but gentle throttle, so basically any cruising or general green lane use, its a nightmare!

There also seems to be so much discrepancy on people's thoughts in what part of the throttle range is controlled by what.

My understanding is: Idle = PJ and air screw / Light throttle = pilot jet and needle / light to 2/3rd throttle = needle and full throttle = main jet. With the obvious overlap between each.

Is this the definitive answer?

I've only had the bike a short space of time but if this is what owning a carved 2 stroke is like its getting flogged asap, nightmare!!

Reeds are fine, no fuel blockages or gunk, new plug fitted and the air filter is clean!

Any thoughts guys? Thanks so much in advance
 

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Stock needles are no good for light throttle work. It’ll always be rich and rough.

Get hold of an NECJ or NEDJ needle. It’s a Suzuki RM needle but it’ll be very different. It has a longer straight diameter before getting on to the needle taper. This straight section (diameter) to taper change is your issue on the stock needle.
 

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If you aren't a jetting nerd the JD kits can be of great help. I used them on many two strokes and they worked on almost all of them.
 

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Discussion Starter #32
Stock needles are no good for light throttle work. It’ll always be rich and rough.

Get hold of an NECJ or NEDJ needle. It’s a Suzuki RM needle but it’ll be very different. It has a longer straight diameter before getting on to the needle taper. This straight section (diameter) to taper change is your issue on the stock needle.
Ok cool - will get one ordered! Thanks dude
 

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Thanks dude but I'm sure the bike should run reasonably well with stock needles - there's no way anyone would've bought one if this is how they run out the factory!
I still think you're chasing a unicorn. They all run like that under light load and constant throttle. It's because they are simply not designed to be ridden like that. They are supposed to be ridden like this:

Brap, brap, braaap, braaaaaaaaaaaaap, brap, brap, braaaaaaaaaaap.... Ring ding ding ding...

But the NEC/D needles do make it a lot better at the expense of a rich top end.
 

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Discussion Starter #35
I still think you're chasing a unicorn. They all run like that under light load and constant throttle. It's because they are simply not designed to be ridden like that. They are supposed to be ridden like this:

Brap, brap, braaap, braaaaaaaaaaaaap, brap, brap, braaaaaaaaaaap.... Ring ding ding ding...

But the NEC/D needles do make it a lot better at the expense of a rich top end.
Haha that made me laugh out loud! I know what you're saying, but its currently a nightmare laning. Is there a real downside to a rich top end?
 

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They can be made to work on light throttle and load. You do have to do a lot of testing though to find the right blend of pilot, AS setting, needle diameter and it’s straight length (in relation to your float level). Most don’t have the patience so make do and just put up with it. The smaller the motor the harder this is I feel.

Very satisfying when nailed though. It ain’t cheap buying all the jetting options though.
 

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All of Pindies advice plus knowing that the pilot will be at its best between 1 and 1.5 turns out on the airscrew. Having to have airscrew turned in further because of hanging revs means richer pilot required whilst winding out further than 1.5 due to overly rich condition will mean weaker pilot required.

I have used ktm and jd needles but for me jap needles were the best (trail riding in the main)

The main jet will be best as rich as you can get away with if you do lots of fast stuff / road work.

Remember pilot will deliver fuel all the way through the range.

The 'smokn' easy adjust airscrew and idle screw will save carrying a screwdriver to adjust.

Get your float level right and make sure reeds and breather pipes are good. Ensure also no airleaks on intake.

If that fails .......
 

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A good test is remove your main jet then ride. It’ll run absolutely as normal until you get to the range the main is important. Without a jet in place it floods, puts the fire out and will be rough as you like. Most will be surprised with this test. Some will find out they don’t even need a main jet in place. If you are the latter then your focus needs to be at the lower end and clip/taper. Don’t piss about micro analysing jetting areas you don’t use. Most of people’s throttle use on trails and road (unless a drag loon) is on the clip and taper at best. Same goes for woods. You ain’t on the main unless on a 125.
 

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Seems all you need are additional two strokes and a pink helmet ;-)
 
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