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I am sad that I did not get any further with my Gasser and I was unable to get rid of the pinging, but on the KTM we achieved a huge improvement.
Even though you and Sand are taking the piss out of my choice of needle I'm still prepared to help you! :p

I have noticed that I can get my engine to ping but only under certain conditions....70MPH at 50% throttle. I don't actually find myself in this situation very often, on the road I normally ride at 60MPH max and that is with 14/48 gearing. (The tall gearing may help me avoid the 'flip' that Sand believes to be inevitable! 🤪 )

I have started to modify a NECK needle so that it is richer from about 40% throttle up to WOT, its tricky to do because I needed to create a good method of being able to take diameter readings at various points along the needle, I've now good a good method, I'm only doing this as an experiment, I'm not suggesting that anyone needs to do this.

The only problem I've got is that I only took a couple of readings from the standard needle, I should have taken 5 readings, I have another NECK needle on order so I can measure that when it arrives.

All of this may be moot anyway once George and JD have their new needle ready.

By the way the NECK needle is leaner on idle, it has a thicker parallel diameter but that does not mean that it is leaner when on the actual taper at 30% to WOT, I will know for sure when my new NECK arrives.
 
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Sidecarbod, steveman, sand300, and others I may have missed, thank you for your time and effort to make the STIC Metering Block a better product. It was originally designed for aggressive MX riding, however, I soon learned there were more discerning (eagle-eyed, perceptive, judicious, shrewd) riders out there (you guys); that were more determined to have lower speed finesse, that led me to make the necessary changes to please many of the riders. Interestingly, the STIC methodology and circuit design and system activation remains unchanged, so, I know it is a great system, it just needed you guys, thank you. George
 

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Good to see this coming to a happy and productive ending with some good old fashioned tinkering where man meets physics and machine, thing obviously works and the poor old guy took some stick to get to this point. Great effort guys, well done.

Still like my Lectron... but more importantly a carby 300 so enjoyed reading that.
 

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Even though you and Sand are taking the piss out of my choice of needle I'm still prepared to help you! :p

I have noticed that I can get my engine to ping but only under certain conditions....70MPH at 50% throttle. I don't actually find myself in this situation very often, on the road I normally ride at 60MPH max and that is with 14/48 gearing. (The tall gearing may help me avoid the 'flip' that Sand believes to be inevitable! 🤪 )

I have started to modify a NECK needle so that it is richer from about 40% throttle up to WOT, its tricky to do because I needed to create a good method of being able to take diameter readings at various points along the needle, I've now good a good method, I'm only doing this as an experiment, I'm not suggesting that anyone needs to do this.

The only problem I've got is that I only took a couple of readings from the standard needle, I should have taken 5 readings, I have another NECK needle on order so I can measure that when it arrives.

All of this may be moot anyway once George and JD have their new needle ready.

By the way the NECK needle is leaner on idle, it has a thicker parallel diameter but that does not mean that it is leaner when on the actual taper at 30% to WOT, I will know for sure when my new NECK arrives.
Of course a bit of banter makes the whole story more fun. Your gearing is indeed tall and I wonder if you use first a lot in hard or extreme sections. However, my bike pinged a lot, Bossi's KTM didn't even when I tried to get it in that range at high revs with closed throttle. God knows why there is a difference.

As far as I know the NECK's straight diameter is one step thicker than the NECJ, which may lead to a very crisp and clean feeling at low throttle openings. Some people (not you!) miss that the NECK is a full clip leaner than the NECJ and I believe that this is the reason for the snappier feel, not the difference in the straight diameter. I am pretty sure that the NECK is leaner at all throttle openings, at least my bum says so.

SBC, I really admire how deep you get into this and I always appreciate your different approach compared to others. Please keep me in the loop!
 

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Of course a bit of banter makes the whole story more fun. Your gearing is indeed tall and I wonder if you use first a lot in hard or extreme sections. However, my bike pinged a lot, Bossi's KTM didn't even when I tried to get it in that range at high revs with closed throttle. God knows why there is a difference.

As far as I know the NECK's straight diameter is one step thicker than the NECJ, which may lead to a very crisp and clean feeling at low throttle openings. Some people (not you!) miss that the NECK is a full clip leaner than the NECJ and I believe that this is the reason for the snappier feel, not the difference in the straight diameter. I am pretty sure that the NECK is leaner at all throttle openings, at least my bum says so.

SBC, I really admire how deep you get into this and I always appreciate your different approach compared to others. Please keep me in the loop!

Hi Steveman, don't worry, I know it's only 'banter'

With regards to my gearing I guess what I do would be called trail riding (green laning in the UK). Speeds are anywhere from 10 MPH up to 60 MPH (Don't tell the TRF!), I've touched 70 on the odd occasion but that's really pushing it!. I find that even with my gearing I'm in 4th or often above most of the time. On the road I tend to keep 60 as a max MPH. The STIC and a high CR head allows me to just sort of 'float along' at low revs in a high gear, I can still pick up the front wheel when required.

The NECK is classed as being one step leaner than the NECJ, and it certainly is thicker on the parallel section, 108.40 thou compared to 108.10 thou. Having said that the NECJ has a parallel section that is approximately 1mm longer than the NECK, because of this I can say the the NECK is leaner on idle but it may well not be leaner as the throttle is cracked open. With a normal carb where the idle fuel is delivered by the idle jet then the needle might not make much difference to the idle mixture but that is certainly NOT the case with the STIC block.

When my replacement NECK arrives I can compare it to the NECJ at various points along the tapers as I now have a good method of doing this to work out which is leaner at 10%, 25%, 50% throttle etc.

I have thinned down my NECK from around 30% throttle to WOT in order to see if I can get rid of the slight pinging that I have. I still have a small amount but i think its getting better. (I really need a standard NECK so I can quickly swap between the two needles)

With regards to all the testing that I'm doing bear in mind that I'm 'working' from home, so I can either do 'work' or I can disappear into my garage to fiddle about with my bike, guess which option wins?
 
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After all these threads/pages, does this mean needles still work like needles after all? Diameter, clip position, taper and where taper starts are all relevant on a normal carb big time. Get one off and it affects the adjacent part to some degree. I was led to believe all that went out the window with a STIC and you all used the same needle (125-500cc) which always seemed a bit odd. Now it seems people are saying needles do influence things when using a STIC, same as without a STIC???
 

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After all these threads/pages, does this mean needles still work like needles after all? Diameter, clip position, taper and where taper starts are all relevant on a normal carb big time. Get one off and it affects the adjacent part to some degree. I was led to believe all that went out the window with a STIC and you all used the same needle (125-500cc) which always seemed a bit odd. Now it seems people are saying needles do influence things when using a STIC, same as without a STIC???
I can only comment on my bike really. The needle does change the mixture strength in the normal way from just off idle to around 3/4 WOT but the needle also has a big effect on the idle mixture and I think this is what differs from a normal block, I would say that the needle diameter and clip are about 95% responsible for the idle mixture (and I guess the air screw is too).
The STIC block does have an idle jet but in my experience it seems to effect the 2-10% throttle more so than the idle. From memory I seem to recall the STIC block being described as a single jet metering system. With the STIC block the clip position effects both the idle and up to about 10-20% throttle, at the moment I never seem to get off clip 1 but George and JD are developing a new needle, hopefully it will work for me on clip 2 or even 3!

People in the US seem to be able to run a different needle than the people in Europe but having said that a few people in the US also prefer the 'Europe' setup. The US setup is bad on my bike and I think Sand300 would agree. I have wondered if the US fuel differs in some way but I guess that is a 'long shot'
 
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USA fuel is ethanol heavy, far more so than europes (hence their better fuel additives to combat ethanol).

They will also have far greater elevation by and large l would have thought.
 

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How come clip 1? Is it to rich by going to 2 or clip 3? If so that’d make me thing I’m on the wrong needle series.

My reason for saying this is that there’s probably in excess of 5 needles at any one time that will work well, especially in my 150. It’s really noticeable if one tiny thing isn’t quite right. This is an issue if you want a certain feel/response at an exact point in the power- probably why many give up on jetting as they get lost in all the variables. On a 250/300 you can get away with it to a certain degree. On a small bore it’s the difference of the bike working and a joy or a nightmare.

With what is now being said about needles and STIC it makes me think things are now dialled in far tighter than before- especially for the UK/Europe region. Yank jetting never works for me over here on any bike I’ve owned which is why I couldn’t understand the insistence of one needle/jets do all. Now the info is more focussed it makes more sense.

I’d like to try a UK spec 125/150 with the STIC in comparison to my 150 which for me is bang on after many tweaks.
 

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Dear Pindie, you will be happy to know, in November this year 2020, STIC will have a new needle (white tip) with dimensional changes that will allow the needle to be in the 3rd clip with the same characteristics as the needles that sandman, sidecarbod are using in the number 1 and 2 clips. The new needle package that will come with each STIC block, will have a Red, White, and Blue needles.. Each new STIC block will also come with the longer air screw that will have a double spring set up, thus. allowing one to run the older air screw out to 4 and 1/2 turns out, further, the new Keihin carburetors coming from STIC will have air correction jets to replace the air screw, thus ensuring better tuning with greater reliability. George
 

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Newsletter # 60

STIC users, you will be happy to know, through the efforts of James from JD Jetting, in November this year 2020, STIC will have a new needle (white tip) with dimensional changes that will allow the needle to be in the 3rd clip with the same characteristics as the needles that are using in the number 1 and 2 clips. The new STIC needle package that will come with each STIC block, will have Red, White, and Blue needles. Each new STIC block will also come with the longer air screw that will have a double spring set up, thus. allowing one to run the older air screw to 4 and 1/2 turns out, further, the new Keihin carburetors coming from STIC will have an optional air correction jets to replace the air screw, thus ensuring more precise air filtration of the air correction system to ensure more precise tuning with greater reliability.

Yes, the STIC is a great lugging system even from idle, with great acceleration, over-rev, and temperature insensitive as evidenced in this TOKYO Off-Road video. Cheers, enjoy

 

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Hi Steveman, don't worry, I know it's only 'banter'

With regards to my gearing I guess what I do would be called trail riding (green laning in the UK). Speeds are anywhere from 10 MPH up to 60 MPH (Don't tell the TRF!), I've touched 70 on the odd occasion but that's really pushing it!. I find that even with my gearing I'm in 4th or often above most of the time. On the road I tend to keep 60 as a max MPH. The STIC and a high CR head allows me to just sort of 'float along' at low revs in a high gear, I can still pick up the front wheel when required.

The NECK is classed as being one step leaner than the NECJ, and it certainly is thicker on the parallel section, 108.40 thou compared to 108.10 thou. Having said that the NECJ has a parallel section that is approximately 1mm longer than the NECK, because of this I can say the the NECK is leaner on idle but it may well not be leaner as the throttle is cracked open. With a normal carb where the idle fuel is delivered by the idle jet then the needle might not make much difference to the idle mixture but that is certainly NOT the case with the STIC block.

When my replacement NECK arrives I can compare it to the NECJ at various points along the tapers as I now have a good method of doing this to work out which is leaner at 10%, 25%, 50% throttle etc.

I have thinned down my NECK from around 30% throttle to WOT in order to see if I can get rid of the slight pinging that I have. I still have a small amount but i think its getting better. (I really need a standard NECK so I can quickly swap between the two needles)

With regards to all the testing that I'm doing bear in mind that I'm 'working' from home, so I can either do 'work' or I can disappear into my garage to fiddle about with my bike, guess which option wins?
I see, I am riding in the first three gears 90% of the time so doing 80kph is something that almost never happens. Also we do not ride on public roads or tarmac except it is necessary to get from one playground to the next. If we do it, it is illegal :)
I think that the length of the parallel section has no or almost no affect on idle, I believe it is just it's bigger diameter that makes it crisper drom idle to about 5%, just talking about the smallest throttle openings possible. But I am always learning new things so you can always teach me something.
I am looking forward reading your comparison between NECK and NECJ. Can't remember that anyone has ever done it so precisely.

Didn't know you work from home but I had put my bet on the garage :) LOL I am unemployed since years and that has lots of advantages, so the garage is my second living room. Sometimes I just sit there, drink a coffee and look at the bikes. Bit strange I know but unfortunately I can't afford a Porsche to drive around just for fun. A lotto jackpot would make live easier but it seems that wont happen. The good part is, I had already everything necessary (apartment, bikes, cars) when I was fired and my van will survive the next 5 or 6 years and that is all I really need for having fun and it is still affordable. Overall I am a happy man and I love spannering and improving things. That is why I always wanted to try a STIC. It seems the STIC works with KTM's. I had two units installed on KTM's, the first version with the .114 tube. Funny thing is they both worked well but not as good as the last one. The strange part is, that I used JD_red needles, but not those designed for the STIC, I used the older ones from a KTM kit and they worked very good (in clip 2).
 
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The white tip needle is the leanest of all 3? The fatter diameter of straight section makes it leaner at 1/8th throttle (just as you open it). The Suzuki needles have a longer straight section so are great for slight throttle movement on a bigger motor and for the rider who doesn’t want kick in the nuts power at that part of the throttle. Yes it’ll feel sharp (because it’s a leaner needle) but that’s only good if your nibbling at the throttle opening.

In my experience, if I tried the same needle in the 150 it’d be utterly horrid and very on/off power as you tend to use far more throttle range than on bigger motors. I.e. I run N1EF in clip 4 and a 48 pilot. Heading to a needle like NECJ in clip 1 or leaner and it’d be terrible. NECJ around 5 steps leaner diameter at a crucial part of throttle on a 150. It’d also be a leaner needle on the clip. The little motor needs a large and fast dump of fuel to get it going. Once it’s going You either run clip three for sharp power on fast flowing stuff or 4 for wider openings on steep hills/technical going.

White needle seems the wrong way for a small bore motor to me.

Has Jim D done any graphs showing how the needle character affects power on 125/150? It’d be good to see.
 

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White needle seems the wrong way for a small bore motor to me.
I think that the STIC block will come with a range of needles, blue red and white, you can then pick the needle that suits your engine size and riding style. Obviously this goes against the "one needle fits all" statement but I guess things evolve.

BTW the white needle will have a long parallel section in the same way that the JD Red II II does now, it has a longer parallel section than any of the Suzuki needles, the red needles diameter, however is less than most of the Suzuki needles. (maybe all of them).
 
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The new STIC white needle does not exist until Mid October; it is currently being made after input from several people including sidecarbod, steveman, and others that were using the needle in the 1st and 2nd clip will now be able to use the white needle in the 3rd clip. The tip of the needle is .002" thousandths bigger. This combination has been carefully thought out with a number of people and with the three needles (Red, White, and Blue) this should allow a person to cover the full spectrum of adjustments.
 

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Question: Has Jim D done any graphs showing how the needle character affects power on 125/150? It’d be good to see.

Answer. The needles will be thoroughly tested before they are released. George
 

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Discussion Starter #337
pindie: I'm yet to try a stic on a 125/150 . I will get round to it one day soon.

I've tried it on lots of bigger bikes though . rm250, ktm 250/300 , gasgas 250, cr500. all have ran lovely and all very very close in terms of jetting.

so far my conclusion is any needle can work and run clean (with better manners I.e smoother power) than a stock keihin.

my advice now is whatever needle you like to run on your ktm150 keep it. 52 pilot, 7 slide and then go armed with a bunch of main jets ranging from 195- 210. systematically start at the smallest and work your way through till it runs clean and strong through the rev range. a 'pipey' needle will still be just that. the characteristics of the needle dont change.

as sidecarbod said, the needle has far more influence over tickover/ low rpm than the pilot jet does.

you can always fine tune with going 1 size up or down on the main (this affects the whole rev range imho), A/s setting and slide cut out.

theres a sense self adjustment to the stic. I cant explain this. maybe george can. I'd always wondered why once you reach that syphon break point to run clean on the bottom end it just so happens to be right for the top end too. whatever the reason it really does work.
 

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Sand300, thanks for the opportunity to explain what the STIC does. Conventional carburetors depend on atmospheric pressure acting on the fuel surface in the holding chamber (aka the float bowl). Then whatever the low-pressure drop is at the tube outlet into the bore; the difference in pressure (higher pressure flows to lower pressure), this is called a differential pressure drop, in the conventional carburetor the atmospheric pressure must also push the medium, in this case the gasoline The STIC system has a unique concept, wherein it has a “auto selection” feature that causes a self-created pressure drop above the wet level; this does not exist in any carburetor in the world. Presently, the STIC automatically selects the higher prevailing pressure from multiple sources, this includes intake back-pressure, the prevailing atmospheric pressure, and the self-generating acceleration chamber, among other planned sources. The self-generating acceleration pressure feature is also transmitted to the STIC’s tube in its outlet. With this feature of “auto selection” the STIC can determine input from the rider, changes in terrain, and the engine size (each engine creates different intake pressures). This STIC feature is real-time, faster than the ECM computer that must receive input from close loop sensors. In summary, the STIC develops an extremely high differential pressure drop above the wet (liquid) level, and the STIC “auto-selection” is pressure loaded and is able to make instant decisions 100% of the time the engine is running. Hope that makes it a little clearer.
 

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Great explanation, thanks for that... figured it was a different way of creating a “fuel signal” like the Lectron does vs a conventional carb. For all that a conventional carb has been superseded by fuel injection, it’s far from a relic, it’s a pretty clever device, lot of complex stuff designed into it. How it generates that fuel signal is its main Achilles heel though... ride a two stroke in heavy mud/soft sand and you’ll know what it’s like to feel it load up and bog, whilst the big four strokes tractor on.

Change the way that it creates that fuel lift and you have a winning idea. Clever stuff.
 

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Great explanation, thanks for that... figured it was a different way of creating a “fuel signal” like the Lectron does vs a conventional carb. For all that a conventional carb has been superseded by fuel injection, it’s far from a relic, it’s a pretty clever device, lot of complex stuff designed into it. How it generates that fuel signal is its main Achilles heel though... ride a two stroke in heavy mud/soft sand and you’ll know what it’s like to feel it load up and bog, whilst the big four strokes tractor on.

Change the way that it creates that fuel lift and you have a winning idea. Clever stuff.
Thanks for your response. Yes I thought of tht (lifting the fuel and it does that), however, the STIC sensing circuit instantly reacts to a load, like mud, or difficult terrain, and will instantly change the differential pressure, thus increasing the torque on demand. The normal carburetor will not do that, in fact the two stroke will normally lay down. Observe the recent TOKYO run up the hill. Also observe this 125 in deep sand without boggin. I have dyno report showing three time more HP off idle, email me at [email protected] and I will send you copy. Study these videos carefully and you will see the STIC has aggressive torque right off idle and any place in between to wide open. Thanks for reading my comment and the observation

Dirt N Iron 2020 YZ125 Trail (same Jetting as MX)

TOKYO on YouTube in a recent hill climb.

Dirt N Iron 2020 YZ125 Trail (same Jetting as MX)
 
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