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Thread: Speeduino 2T EFI Project

  1. #1
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    Speeduino 2T EFI Project

    Quote Originally Posted by TZ350 View Post
    Ecotrons sells a two stroke EFI kit, and I have been using one, the problem with their kit is that it only allows for the Alpha-N tuning control protocol. Making power has been easy but drive-ability has been my stumbling block for a long time and I did not know what was making the tuning so difficult. Now I know a Alpha-N map on its own is not enough and that I also needed a VE map to get drive-ability out of the corners.
    Moving on from Ecotrons, and Ecotrons is past history now I am moving forward with a Speeduino for my 2T two stroke EFI project.

    https://speeduino.com/wiki/index.php/Speeduino

    The mission is to find a way of taking a MAP value from the varying pressures in my two stroke crankcase so I can use a VE table for fueling control.

    The Arduino based EFI development project, "Speeduino" sells add on boards to convert the Arduino Mega 2560 to a EFI CPU and they supply them with open source firmware that can be modified by the end user, using the Arduino or other C++ code editors.

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ID:	338117 The Speeduino is an EFI shield for the Arduino Mega 2560 Click image for larger version. 

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    As well as all the EFI and Ignition IO the Speeduino board also has a development area where you can add your own IO and change the Arduino software code to suit, so very flexible.

    The Speeduino is aimed at cars but it also has a 2T option and I like it because I can change things and should be able to modify the open source software to get a timed crankcase pressure reading for a sample and hold MAP value. It is what I need for the next step in my 2T EFI project.

    https://speeduino.com/wiki/index.php/Speeduino

    .
    - Team ESE -



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    What I have learned about 2T EFI so far .... A

    Use the smallest injector possible. This is important because it gives you the widest range of tune-ability possible.

    A small injector delivers enough fuel but as RPM goes up a small injector runs out of time to deliver the fuel required and a bigger injector is needed to deliver the same amount of fuel in the shorter time available. For high revving two strokes staged injection is must.

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ID:	338131 It is all about the available time to get stuff done.

    When a EFI 2T engine gets the hurry up, it becomes all about the diminishing amount of time to get the good stuff in there.

    Quote Originally Posted by TZ350 View Post
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    Blue - RPM, Yellow - maximum injection time, Green - small injector, Red - big injector

    Starts with the small injector, swaps to the big injector then runs both at the same time.
    A small injector for small TP throttle position and a big one for big RPM. Because there is a minimum on time for an injector a big injector can not be turned down enough to fuel properly at small throttle settings. An injector big enough to get the job done at 12,000 rpm floods the engine at lower rpm or throttle position.

    The cross over for staged 2T injection is about 9 or 10K rpm. Over that and you need two different sized injectors.

    There are physical injectors and logical injectors.

    A physical injector is just a physical injector and a logical injector is two or more physical injectors treated as one by the EFI's CPU and fired together.

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    My 13,000 rpm NSR110 cylinder needs staged injection and has three physical injectors but only two logical injectors as the B port injectors are fired together as one.

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ID:	338056 B port injection. Flettner was injecting 2T's this way before KTM did.

    The YZ250 cylinder does not need staged injection as its RPM ceiling is less than 9,000rpm and one size of injector can cover the tuning range required. But it has two physical injectors for symmetry and they are treated as single logical injector by the EFI's CPU.

    ...... the timing of the Injection end point is critical .....

    For me it was BDC where the pipe is sucking its hardest, Flettner prefers just before transfer port closing, but whatever, your engine will have a sweet spot and it pays dividends when you find it.
    - Team ESE -



  3. #3
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    What I have learned about 2T EFI so far .... B

    For simple EFI there are two basic tuning protocols, Alpha-N, and VE, volumetric efficiency.

    Alpha-N is TPS vis RPM and VE is RPM vis MAP.

    TPS indicates changes in the size of the hole through the throttle, changes in the size of the hole don't necessarily indicate actual changes in air flow through the hole but MAP, manifold absolute pressure indicates these changes.

    Alpha-N by itself maybe works Ok on basic industrial and low powered 2T's, and anything that does not rely heavily on its pipe for power. And Alpha-N is great for power and all positions where the air flow is predictable but totally useless for drive-ability on a highly strung two stroke with fussy resonant tuning.

    Alpha-N by itself will maybe work Ok up to about 9 bar BMEP after that something like VE is needed too for drivability. Highly strung 2T's are typically 11-14 bar BMEP. The problem with Alpha-N is that it does not allow for possible changes in air flow at the same TPS vis RPM setting.

    On a high performance two stroke the wave action in the pipe collapses when the throttle is closed. When the throttle is opened again the noise comes back immediately but the strength of the wave action in the pipe and therefore air flow through the motor takes some moments to build up again.

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    Same Alpha-N TPS vis RPM position but different airflow's through the motor due to the different strengths of the wave action in the pipe. Because it can't adjust itself for the collapsed air flow, Alpha-N will over richen the mixture or even flood the motor when you are trying to exit the corner.

    Alpha-N is only really good for near wide open throttle power when the motor is singing and the airflow is consistent. For drive-ability out of the corners a VE, RPM vis MAP, manifold absolute pressure or similar protocol is required to account for changes in air flow induced by the wave action collapsing in the pipe.

    Making power has been easy but drive-ability has been my stumbling block for a long time and I did not know what was making the tuning so difficult. Now I know a Alpha-N map on its own is not enough and that I also needed a VE map to get drive-ability out of the corners.

    Traditional four stroke methods of measuring air flow through the motor or manifold absolute pressure don't work in a two stroke so some other procedure is required. Not much that is four stroke translates over to two strokes.

    What we need is a two stroke method of seeing changes in air flow through the motor and I think this can be done by looking the changes in the difference between the peak vis low pressure cycles in the crankcase.

    I have already worked out a method and an algorithm for doing this.

    Quote Originally Posted by TZ350 View Post
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    I have been making progress with the simulated MAP idea.

    I have abandoned my original idea of using a MAP sensor to see the high and low pressures because MAP sensors are too slow and instead will use a piezo element.

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    Because all the peak pressures all line up at the same crank angle I have embraced Flettner's idea of "sample and hold" by making only one timed measurement at peak pressure and using that for the complete cycle.

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    I have been able to use some PC based software to generate a simulated ignition trigger pulse and crankcase pressure trace for my software's test and development purposes.

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    The code is pretty simple, an interrupt triggered by the ignition trigger pulse at which time it waits about a third of the duration between pulses and then samples the crank case pressure. The loop writes the simulated MAP output signal that then goes to the EFIs CPU.

    Simple code but it took a while to get it and my test setup to work reliably over the full RPM range.

    Ecotrons .... Alpha-N, by itself is not a good enough tuning methodology for a high performance 2T
    - Team ESE -



  4. #4
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    What I have learned about 2T EFI so far is to go here .... C

    ...... the timing of the Injection end point is critical .....

    Follow the posts link back because there are lots more as well as video's of EFI 2T's being ridden in the field.

    Quote Originally Posted by TZ350 View Post
    I have learned from Flettner, that a competition two stroke can be successfully fuel injected and that EFI can work very well on 2T's.

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    With Flettners guidance and his example of two very successful working bikes using the Link EFI unit, one on E90 and the other on pump gas I have been encouraged to have a go myself.

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    Blue line is the Fuel Injected YZ250 (pump gas) and Red line is the Kawasaki Big Horn (E90).

    The first lessons I had to absorb were that the timing of the Injection end point is critical on a two stroke and should be timed to end at transfer port closing and the fuel should be injected into the transfer ports, either counter stream like the YZ250 or across the port like the Kawasaki but definitely not straight into the inlet or the crankcase itself. To be successful the full fuel charge has to be inducted into the cylinder on each cycle otherwise you get rich/lean cycles and poor running.

    As I understand it: with a carburetor, any time air moves fuel gets mixed with it, so all the inducted air in the crank case has air with fuel more or less evenly mixed throughout it.

    With a fuel injection system that has discreet injection pulses and with the injector at the inlet only some of the inducted air will have fuel mixed in with it. Now inside the crank case there are patches of air with no fuel, and some over rich areas.

    With inlet injection its random what air/fuel mixture strength gets sucked into the cylinder, you might get a few lean cycles then a heavily over rich one and this is what is happening when the motor is hunting. And if you richen it up so there is no lean cycles then the whole thing goes so rich that the motor will barely run at all.

    As we all know, a certain amount of air requires a certain amount of fuel. But with inlet injection the fuel does not get mixed evenly into the air as it passes through the crank case so you have no chance of controlling the exact amount of fuel being inducted into the cylinder with inlet port injection.

    But with transfer port injection you have a much better chance of controlling the exact amount of fuel that gets inducted into the cylinder on each cycle.

    (direct injection into the cylinder is another very good approach to 2T EFI, but I cant easily get suitable fuel injection parts to try that).

    YZ250 counter flow injection makes for good air/fuel mixing.
    EFI Kawasaki BigHorn running transfer port injection and E85. Runs to 8,000 rpm

    Some more Youtube clips of transfer port injected 2T's
    http://youtu.be/eleqBGvOM4M
    http://youtu.be/hOGZ5llowoU
    http://youtu.be/1YG9ko8-Nwk
    http://youtu.be/UEQli7nuak4
    GerbilGronk is worth a Youtube search.

    I have been working on a EFI transfer port injection system of my own but trying to take the concept to 12,500rpm and that means staged injectors.

    https://www.kiwibiker.co.nz/forums/showthread.php/159112-Ecotrons-Engine-Management/page11

    Quote Originally Posted by TZ350 View Post
    Posted this because someone asked me about the jerky response they are getting now that they are running split injection. Ie they are using a small injector for slow running and a large injector for power. I think the issue is in the size of the step on the map at the point where the ECU changes from the small injector to the larger one.

    The Ecotrons Alpha-N map is not a fuel map but a map of predicted changes in engine load (torque) with respect to TPS and RPM.

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    It is like a stair case and to keep the Load steps even, it is possible to cluster the rpm steps around the area of rapid changes in Load (torque). And on my dyno graph that is 7,500 to 9,500 rpm (yellow line). Above that the power goes up with rpm but the change in Load is a lot flatter. So you can have quite wide rpm steps below and above where the engine comes onto the pipe and cluster the rpm steps where the Load (torque (yellow line)) curve climbs rapidly so as to have even predicted Load steps across the complete rpm range from 3,000 to 13,000.

    Ie on my map the first rpm point is at 3K rpm, the second is 6k the third is 7k then 7.5k, 7.75k, 8k, 8.5k, 9k and rpm step 9 is 9.5k step 10 is 11k then 12.250 and finally 13,250 rpm. So the spread of rpm points is chosen to get even changes in the Load steps.

    My TPS steps are 0, 10, 12, 15, 18, 20, 26, 31, 36, 41, 46, 51, 61, 71, 85, 98. there is much greater changes in air flow at low TPS than there is above 70%. If you look at the dyno graph everything above 70% has pretty much the same power output.

    What I think happens when split injection does not work properly and jerks all around the place is that when the small injector gets to a load cell step that is to big and would max it out the ECU swaps to the big injector which squirts to much fuel for the rpm (because the min on time for the big injector flows to much fuel) and the rpm drops back below the small injectors last effective load cell and the air/fuel clears and the rpm slams backup and the cycle violently repeats itself. Now a smaller big injector might help but a disparate size in the load steps can be the real problem.

    This will not be confined to a set rpm position on the map but a patch of Load cells where the effective differences in predicted Load is to great. And I expect the ECU's hysteresis between injectors will play a part here too.

    The trick is to group the RPM columns and TPS rows in such a way that the changes between adjacent Load cells in any direction are much the same.
    About choosing the RPM steps for a Alpha-N map. Its worth following the post links back as there is lots more good background info there.

    https://www.kiwibiker.co.nz/forums/s...agement/page11

    Quote Originally Posted by TZ350 View Post
    The EFI lesson I learnt last month was, that to get the greatest range of tune ability I needed to use the smallest injectors possible that will still do the job. I know, pretty obvious, but there you go.

    I read the Ecotrons EFI manual and saw that the map must have as many even steps as possible and I thought that meant dividing the rpm range up as evenly as possible, seemed logical, but wrong again.

    The bike bucked around swapping between the staged injectors as the EFI struggled to jump from one cell to another on the steeper parts of the fueling curve.

    I guess what they really meant was that the changes in load between cells needs to be as even as possible.

    So I don't need even spacing between the rpm break points and can have big or small gaps between them so long as there are no big steps between the load values in adjacent cells.

    Attachment 308859

    I can now throttle on/off pretty well and do a series of part throttle runs, the last one is at 30% TPS, it looks a bit lean.

    Its not perfect but it is running a lot better.
    Ok, so I can make good power with Alpha-N but in the end for me, the Alpha-N method by itself has became a dead end because it does not adjust for changes in the mass air flow induced by changes in the strength of the wave action in the pipe. This is something that becomes ever more of a problem as the BMEP increases and the engine becomes ever more reliant on fussy resonant action in the pipe for its power.
    - Team ESE -



  5. #5
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    What I have learned about 2T EFI so far is to go and here .... D

    A lot of back story here:- https://www.kiwibiker.co.nz/forums/s...agement/page11

    Some helpful input from Dmcca and Wob on how to use a wideband O2 Lambda sensor to tune a 2T.

    Putting the Lambda in the stinger, seems to be way more stable and repeatable when logging the A/F data.

    Originally Posted by TZ350
    The Ecotrons EFI has barometric and air temperature sensors for automatic fueling compensation so hopefully once I am on the money with the dyno the ECU's auto compensation will give pretty much the same results as changing the jets 3 times a day.

    I feel very comfortable with tuning the EFI system for maximum power, above 50% throttle position that is relatively easy.

    The problem I am struggling with is at the low end, if this was a carb then the EFI bit that is challenging me now is the area covered by a carb's pilot jet and transition to the slide cutaway.

    Originally Posted by dmcca
    May I ask why you're not using a wideband O2 to tune this area? It would be relatively straightforward with a wideband and a brake dyno.

    I started out trying to get a 12.5:1 A/F everywhere on the map, as you do if you don't know any better. Things weren't going well and I gave it away when it was pointed out to me that it was the short circuiting fooling the O2 sensor into thinking the system was running lean when it was not.

    It really confused things and it looked like the O2 sensor was not going to be very useful so I discarded it. But your experience encourages me and it looks like that with a bit more experience myself I might be able to get somewhere with it now I have a better idea of what is going on.

    Originally Posted by Frits Overmars
    Why a brake dyno? Then you would be developing an engine for a set of circumstances that it will never see on a race track. Going through the revs on an inertia dyno and registering revs, torque and lambda simultaneously is an excellent way of establishing an injection map. Besides, running constant revs on a brake dyno with too little fuel or too much ignition advance may kill your engine, whereas it might survive on an inertia dyno.

    Originally Posted by dmcca
    When i say brake dyno i mean an eddy current or similar that allows both constant rpm tests and normal 'runs'... Im sure that doing only constant rpm tests is not ideal.

    Personally I do a combination of both to tune an engine and so far it has worked well for me, especially when tuning the low throttle area that TZ was talking about... in saying that ive only ever had an eddy current dyno, never an inertia-only dyno. And have developed my own methods of tuning without ever seeing first-hand anyone else's process for tuning a two stroke... maybe its a case of ignorance is bliss, however I find my process to be very quick and very reliable for a wide range of engines.

    I find that the lambda sensor is a little slow to react at low revs and part throttle. Its fine at higher revs and higher throttle. By holding the engine at a certain rpm point for 3-5sec at each throttle position it gives the readings time to stabilise and gives much better, more repeatable data.

    I start by doing a range of fixed rpm tests at different throttle openings, with the revs building higher each test... eg 4000, 6000, 8000, etc at 1/8, 1/4, 1/2, 3/4, full throttle. By doing this you can easily see the areas that need changing (pilot, slide, needle diameter, clip position, needle taper, main jet, etc).

    If there is a serious problem with the tune you will always catch it before doing damage as you’ll see AFR's begin to lean out or detonation begin to show before you get too high in rpm. Once I’ve done basic tuning like this then i do full runs and constant load testing and fine tune if necessary, but these are normally only very minor changes.

    Whether the AFR reading is showing true AFR or not doesn’t really matter, the numbers can still be used to tune an engine... around full throttle and peak torque it is fairly reliable to use ~12.5:1 and leaner readings below that, down to around 13.5-14:1 at part throttle/low rpm.

    Of course you still need to use experience and 'feel' to do the fine tuning but the AFR numbers will get you close. Even if the engine is not actually seeing 14:1 at part throttle/low revs, its still a repeatable data point that can be used to tune an engine. Its certainly a lot better than guessing, especially when tuning the part throttle areas.

    Originally Posted by wobbly

    +1 the above.Adding that putting the Lambda in the stinger, seems to be way more stable and repeatable when logging the A/F data.

    Using data this way is something that you really don’t appreciate how good it is until actually doing it.
    Hence TeeZees surprise when I related that every time you change a small item in the engines tune - the dyno result for sure is not telling you really what you want to know, unless you reject every time to hit a predetermined baseline.

    As Jan Thiel said, most all of the pipe testing at Aprilia was a complete waste of time, when he finally realized allot of the power differences were down to how the egt reacted to that pipe. Not that the pipe was "better " for some aspect of scavenging, or trapping efficiency in making more or less power.
    - Team ESE -



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    What I have learned about 2T EFI so far is to go here .... E

    Click image for larger version. 

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    I started out trying to get a 12.5:1 A/F everywhere on the map, as you do if you don't know any better. Things weren't going well and I nearly gave it away before it was pointed out to me that air was the short circuiting fooling the O2 sensor into thinking the system was running lean when it was not.

    "Transfer Efficiency" is the amount of air inducted and passed up to the cylinder.
    "Trapping Efficiency" is the amount of that air that is retained in the cylinder.

    So if the transfer efficiency is greater than the trapping efficiency then the spilled air will make the O2 sensor show lean even though the trapped air is at the correct air/fuel ratio. The indicated Lambda always improves as the motor gets onto the pipe and the trapping efficiency improves.

    I found things worked well when the motor was off the pipe and Lambda indicated 1.2 and on the pipe it was 0.85.

    An indicated Lambda of 0.85 or A/F ratio of 12:1 in a two stroke is great for power.

    Some links to YouTube clips of a couple of two stroke bikes that have been successfully modified for EFI.

    Yamaha YZ250.
    https://youtu.be/hOGZ5llowoU
    https://youtu.be/UEQli7nuak4
    https://youtu.be/1YG9ko8-Nwk
    Kawasaki BigHorn.
    https://youtu.be/eleqBGvOM4M
    https://youtu.be/ifSEql1X4R0
    https://youtu.be/CnIemdISKrM

    Quote Originally Posted by TZ350 View Post
    I have tried a few different places for injectors, some places seemed to be better than others.
    Follow the post link back to see the variations injector position I have tried.

    And this is why direct in cylinder fuel injection wont work on a high performance 2T.

    Quote Originally Posted by FastFred View Post
    Intuition is great for giving you a direction to look in and being able to put (rough) numbers to something like TeeZee does can tell you if you are on the right track or not. Numbers can save you from a lot of wasted time.

    Time at 13k rpm = 4.6ms for a complete 360 deg crank revolution.

    Transfer opening to closing 130 deg. 1.7ms.

    From exhaust port opening to closing 200 deg. 2.6ms

    From exhaust closing to ignition. (with ignition timing 18 deg BTDC). 72 deg. 0.8ms.

    Pressure in the cylinder ATDC greater than the 3 bar fuel injection pressure 90 deg, 1.2ms.

    So somewhere between 1.7 and 2.6ms for injection, 0.8ms for fuel homogenization.

    2-3ms required to open and close the injector 2-3ms required to deliver the fuel another 2-3ms or so to homogenize it.

    Total time required:- 6-9ms

    Is there enough time to get everything done? I am picking not, and I am picking TeeZee doesn't think so either.
    Quote Originally Posted by TZ350 View Post
    With EFI, "Time" is King.
    Quote Originally Posted by TZ350 View Post
    Injector Position

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    Central injector fires through a slot into the underside of the piston.

    My favourite low speed injector position has been to fire under the piston. This seems to help enormously with fuel homogenization at lower and off pipe engine speeds.
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    I have tried the injectors in lots of different places. direct through the port, across the crankcase, inlet, throttle body, bell-mouth but across the transfer ports is my favorite and when that is not physically easy to arrange then straight down the B ports and under the piston is always great for the small injector.

    Quote Originally Posted by TZ350 View Post
    Quote Originally Posted by jonny quest View Post
    TZ350, we rev 250 4 strokes to 15,000rpm all day with a single injector in the throttle body. I'm comparing apples to oranges I know, but still... was shocked to think you need 3 injectors for 13k.
    15,000 4T rpm is only 7,500 2T rpm. Anything 2T over 9,000 rpm is looking at staged injection

    There are actually only two "logical" injectors, one big one small. The two "physical" injectors in the B ports are there for symmetry of fuel distribution and are fired together as one Logical injector. I use three physical 124g/min injectors but the EFI CPU sees only two logical injectors, a 124g/min slow speed injector and one 248g/min high speed injector.

    But it is not about injector size but time available to get the injecting done. If you only have half the time, then you need an injector twice the size to get the job done. And you need a small one for tune-ability when there is plenty of time like <9k 2T rpm (equivalent to 18k 4T rpm) and a much bigger one to deliver much the same amount of fuel when time is getting short like above 10k.

    The reason you can't use the big injector for slow running is because an injector must be turned on for a minimum amount of time to get it completely open and controllable. And a big injector just spills to much uncontrolled fuel while it is opening for idling speeds and small throttle opening.

    15,000 4T maxed out rpm "Time" for an injection cycle is just about where my 2T is starting to come on the pipe and get going. A 4T has twice as much time to get things done so only needs an injector half the size of a 2T, ie something about the size of my slow running injector.

    It is "Time" not injector size that is the real issue with EFI.

    Quote Originally Posted by jonny quest View Post
    a single injector in the throttle body.
    Another issue with 2T EFI and throttle body injection is that unlike a carburetor which adds fuel to the air stream all the time, regardless of whether the air is being sucked in or blown back out of the crankcase ie fuel standoff.

    A fuel injector squirts fuel in discreet blobs. And is just as likely to add all the fuel to the air stream as its blown back out as it is to the air stream being sucked in. So there could easily be rpm patches where you could wind up with little fuel at all in the crankcase.

    This is less of a problem with transfer port injection. Where the bulk of the fuel is concentrated in the transfer duct and not the inlet tract where it can be more easily ejected. And will be one of the reasons why 2T EFI can show improved fuel efficiency over a carburetor.

    And another reason for injecting into the B transfers is that the bulk of charge short circuiting happens from the A ports and if there is little fuel in the short circuiting air then the motor is cleaner and more fuel efficient. Another win over the carburetor which would have loaded all the crankcase air with fuel. With a carburetor all blow back and short circuiting air loses fuel and pollutes the environment, with 2T EFI not so much.
    Quote Originally Posted by Frits Overmars View Post
    If a clear suction signal to the carburetter is no longer needed, you could start opening the RV at about 20° after BDC at max.torque rpm, assuming sufficient transfer angle.area, and even earlier at lower rpm's.
    Opening the RV as soon as the crankcase pressure has dropped to the same value as the pressure upstream of the RV, will prevent the case pressure from dropping much further, which would slow down and eventually reverse the transfer flow.
    - Team ESE -



  7. #7
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    Very interesting, so you can not see or I do not see parts D and E.

  8. #8
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    Quote Originally Posted by ceci View Post
    Very interesting, so you can not see or I do not see parts D and E.
    I havent finished, maybe later today.

    Quote Originally Posted by TZ350 View Post
    Links to a whole bunch of EFI projects. Mostly amature home tuners, and all great work.

    EFI Kawasaki Bighorn on the dyno https://youtu.be/ifSEql1X4R0
    EFI Kawasaki Bighorn Trail ride 1 https://youtu.be/eleqBGvOM4M
    EFI Kawasaki Bighorn Trail Ride 2 https://youtu.be/CnIemdISKrM
    EFI Kawasaki Bighorn VMX https://youtu.be/v8i6ps0PdVI

    Maramarua classic forest trail ride https://youtu.be/ZqzOgOJuJ1E

    EFI YZ dyno run https://youtu.be/UEQli7nuak4
    EFI YZ250 look around and first start up https://youtu.be/hOGZ5llowoU
    EFI YZ250 trail ride 1 https://youtu.be/1YG9ko8-Nwk

    Nath88?
    EFI first start up https://youtu.be/wIRF3VJUqBk
    EFI ride around the block https://youtu.be/4Zsz26QmfAU

    CVT EFI NOS and everything else https://youtu.be/A9d-atuQO7Y
    EFI and Turbo Snow Cat https://youtu.be/U1uz7gdS-cA
    SeeDoo Etec https://youtu.be/LhNHcy9si5o

    1975 Suzuki GT250 road bike fuel injected start up https://youtu.be/A7fONUsJQD4
    1975 Suzuki GT250 road bike fuel injected road test https://youtu.be/BePHcg5dNjw

    Fuel injected 1971 Yamaha R5 https://youtu.be/qzVHgHJ9PWI

    Athena Direct Injection https://youtu.be/h-F_IndOm5I

    BRC 250 EFI kart engine https://youtu.be/dNat9ZwWbq8
    BRC 250 EFI kart engine https://youtu.be/Kfx61bUOznc

    Racing EFI Vespa https://youtu.be/_sjx2i4xFlY

    EFI Banshee first start https://youtu.be/e1WHVVT6d9c
    EFI Banshee run https://youtu.be/eznxX_ndpII

    Direct injection https://youtu.be/IpjWi-0qTJg

    Will direct injection DI save two strokes https://youtu.be/ql2-wW0LuWY

    Orbital direct injection https://youtu.be/fIoB0zTeUAY

    EFI Dragbike Thailand https://youtu.be/VB6Q_fQQ_PY

    Mega Squirt YZ125 https://youtu.be/Di8FuHApLKA

    Aprilia RSi 125 EFI Part 1 https://youtu.be/S1xvr_VXzx4
    Aprilia RSi 125 EFI Part 2 https://youtu.be/j5FOUn7V3nc
    Aprilia RSi 125 EFI Part 3 https://youtu.be/WBaiMJb6ntY
    Aprilia RSi 125 EFI Part 4 https://youtu.be/pZl5KPwvm0s

    EFI 125 kart engine https://youtu.be/4D8WRjDxan0
    EFI 125 kart engine https://youtu.be/b1YbPdw00Ww
    EFI 125 kart engine https://youtu.be/r5ljaDdaH_o
    EFI 125 kart engine https://youtu.be/uexMJbtyZdU
    EFI 125 kart engine https://youtu.be/uzbSsYh8Z9w
    EFI 125 kart engine https://youtu.be/XIcX9-GsMGQ
    Fuel injected Kart https://youtu.be/R5_KlcefQ8k

    2017 KTM dyno https://youtu.be/8g0uSIisMtI
    2017 KTM demo ride https://youtu.be/nf1tfdUtjJI

    EFI CR250 https://youtu.be/VlHyRcmlLgU http://www.supermototecnica.com/2015/09/10/sviluppi-del-sistema-iniezione-diretta-indiretta-due-tempi/

    EFI YZR500 https://youtu.be/tNAtmKzqo9A

    EFI CR500 https://youtu.be/BskSxMoQrwA

    2T Nitro Engine visible combustion https://youtu.be/aO5Qkzlo2Kw
    2T visible combustion https://youtu.be/G7PSec7RjRw
    More 2T Visible combustion https://youtu.be/BrWpF6YiSDs

    Fuel Burn in a side valve 4T https://youtu.be/jdW1t8r8qYc
    4T Visible fuel burn https://youtu.be/31mtOdHGbB4
    - Team ESE -



  9. #9
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    Did you look further into the Aviamechanica controller (or was that someone else?)
    it's not a bad thing till you throw a KLR into the mix.
    those cheap ass bitches can do anything with ductape.
    (PostalDave on ADVrider)

  10. #10
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    Quote Originally Posted by pete376403 View Post
    Did you look further into the Aviamechanica controller (or was that someone else?)
    Yes I took a look but they don't use a MAP sensor, basically it is a modified Alpha-N setup. Very good system for what they are doing.

    Their system can be found here:-

    Quote Originally Posted by jbiplane View Post
    We make our EFI + DC spark ignition compatible with http://tunerstudio.com/index.php/tuner-studio So it completely open for experiments.

    https://www.kiwibiker.co.nz/forums/s...agement/page18
    They use the same tuning application that Speeduino do too.
    - Team ESE -



  11. #11
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    Quote Originally Posted by TZ350 View Post
    I haven finished, maybe later today.
    Sorry for my impatience.

  12. #12
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    Click image for larger version. 

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    My Speeduino ECU kit turned up today. The Speeduino board with all the heavy current handling output, MAP and other IO is made as an Arduino shield and plugs straight onto the Arduino Mega. There is a box too with a handy row of screw terminals that makes experimentation easy.

    The beginners guide to getting going with the Speeduino:- https://speeduino.com/forum/viewtopic.php?f=21&t=221

    These are the Injectors I have been using, good for 13,000rpm

    https://www.aliexpress.com/store/pro...27f53d56DUcmks

    Other motorcycle sized EFI parts.

    https://superturbo.aliexpress.com/st...7d5c6ccdMKczmJ
    - Team ESE -



  13. #13
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    This year 2018 Ktm uses the EFI and in the TPI version, but what kind of TPI they use, the one designed by Flettner, and why they use this and not other types of TPI http://www.supermototecnica.com/2015...tta-due-tempi/.

    The advantage of this type of injection: injected against the current and that makes the size of the drop of the spray is large quickly evaporate gasoline.

    The disadvantage of the others is that the air stream transports the spray droplets instead of evaporating them

  14. #14
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    Interesting link, I notice the guy says he has good drivability. Drivability is my problem.
    - Team ESE -



  15. #15
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    TPI there are several types, this is also TPI:
    https://patents.google.com/patent/US...njection+rotax

    The placement of the injectors is different in the three cases mentioned, but common in the tranfer

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