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Speedpro

125cc twin

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I've got this thing starting  OK now but I can't get my head around a few things.

There seems to be quite a delay with data being displayed on the laptop at times. "Setup Logging" can be slow and swapping between PC and ECU logging can be slow as well. It's probably my old laptop. Configuring gauges is slow to bring up parameters.

The engine easily spins at 800rpm just turning over at start. From what I understand this means the starting enrichment jumps straight to "post start enrichment" then to "warm up enrichment". Making adjustments in these tables hasn't been having the effect I expect. I know this engine when using another system liked 3ms injector pw cold at start. I've cranked in bigger %s but without the increases I expected in pw. It'll start but is very sensitive to throttle while cold. It will happily idle at 2500rpm typically if that could have an effect

Just starting out I'm not sure of the best basic setup. Currently using Traditional method which I'm happy with and the Equation Load source is MAP which I'm really unsure about and MAP vs RPM for the main fuel map. This seems to be easily tuned on my rolling road at fixed load points. However on the inertia dyno where nothing is steady I see problems. With a smaller throttle(25%) the AFR can go lean through load cells where if throttle is at 50-75% through the same cells the AFR is fine. This engine barely pulls any vacuum at anything under 5-6000rpm. The attached log files are from a run in the garage warming it up and looking for an oil leak. There also seems to be a regular cycle to the MAP reading which has a period of about .14s which doesn't seem to coincide with anything that could cause interference. In any case the ignition which would be the usual suspect runs along one frame rail and everything else is along the other. 12V is supplied by a car battery without a battery charger connected so a good stable supply.

What I wonder about is changing the Equation Load source to BAP/MAP. I see a problem though where at a particular throttle setting the turbo could have spooled up but MAP may not have exceeded BAP so certain throttle settings may have different airflow rates dependent on the turbo, or have i missed something. The help files are good but I just can't see how that will work.

Excuse the fuel map, we were playing and it's pretty lumpy. We parked it before we got anywhere with it due to the oil leak.

Suggestions about where to look greatly appreciated.

18_4_2 FZR125 at home logging on.pclr

2018_4_2 ECU log.llg

2018_4_2 PC log.llg

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Thanks, I've been leaning to MAP over BAP. The other thing I have a concern about is the vacuum lines to the MAP sensor. Having individual throttle bodies I combine lines from each port and then have a longer hose to the sensor. I was thinking about either a small canister or a longer/fatter hose to provide smoothing of the pulse. It'll be a balance smoothing and lag.

I'm interested in a small class of bike racing. The 4-stroke limit used to be 125cc but there were no decent engines around when I started this. I scored an FZR250 4 cylinder and using a mates bandsaw and my own little lathe cut cylinders 1&2 off, cut the crank and cams and eventually got it running with carbs and a GSXR ignition. The sound with open pipes at full noise on the dyno gave me shivers. I also had a supercharger and turbo. The turbo was chosen simply because I could fit it with the gear I had in the garage. I also found that an Ecotrons EFI for a Kawasaki GPz250 plugged straight in. Disappointingly, despite me asking and getting assurances, this system was limited to about 15,000rpm and even then I think it wasn't handling it well. So it's a 125cc twin cylinder, 4 valves per cylinder, DOHC, watercooled, turbocharged, full engine management engine. It ran to 19,000rpm on the dyno with the carbs. With the Ecotrons system it was making boost from about 10,000rpm so quite useful range if it would rev out.

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Sorry Im short on time tonight so only had a very breif look at your map.  Most of your set up is fine but you need to change your fuel table axis to TP since you have unstable vacuum.  You may need to enable a 4D table later depending on how restrictive the turbine is but start tuning without it and only add it if needed.

Your AFR target table looks a bit lean for a boosted engine so fix that up as it is used as part of the fuel calculation.

aBUZDGo.png

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Now set to MAP/BAP x-over, main fuel table axis is TP, 4D table activated with MGP on the axis. Very quick run as it's still leaking oil and it starts and runs fine up to about 5000rpm,which is as far as I went, and 20% throttle. The target lambda is just a number I put in. I'll run it on the inertia dyno and see what it actually likes and enter that value. The turbo is an IHI RH31B which is about as small as it gets but I don't see it being restrictive. I'm leaning toward tuning the main fuel table on the inertia dyno to have values which work for a dynamic engine state. If I do it on the rolling road brake the turbo will spool up fully for that load and need more fuel to match. In reality it is more likely to be less than fully spooled up, be flowing less air and need less fuel, in normal operation. I'll tune the 4D table using the rolling road at fixed loads as once you get to boost it'll just vary the MAP/MGP value. Maybe.

Thanks for checking it over

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Read my post again, for the equation I would suggest MAP rather than MAP/BAP unless you cant get it to idle satisfactorily using MAP equation.  Also leave the 4D table turned off (or zeroed) for initial tuning.  With 4D off you then fully tune the whole main fuel table at the lowest boost (wastegate spring pressure).  Once the main table is done you then increase boost and do another run - if Fuel mixture doesnt control at the target at higher boost then turn on the 4D table and use that to fix any area that has become too rich at higher boost.  Usually, if the turbo is reasonably efficient you wont need the 4D table at all.  Only if efficiency drops away at higher boost you will need the 4D table to pull a little fuel out at high rpm/boost.

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Ooookay. Been running the engine on the inertial dyno. Main fuel map is TPS/RPM, turbo has been removed and a simple 2:1 exhaust fitted, cut the number of columns and rows down in the table and letting the software sort it out which it seems to be doing just fine. It sure makes tuning easy. This has been done to ease finding a rpm limit problem. Equation Load source is still BAP/MAP but I have disabled the 4D map.

My problem is that the engine is being RPM limited. Towards the end of a run on the inertial dyno as it gets to about 15-16,000 rpm it starts to richen up and then gets real rich real quick. I have ALL the engine protection turned off but it is still doing it. Just sitting in the garage the Engine Protection page on the tuning screen is indicating a rev limit of 12,000rpm. When I turn on RPM limiting and look at the table it does have a limit of 12,000rpm at 20'. If I change the rpm limit it also changes what is indicated on the Engine Protection page. When I was first looking at the software I did enter values in the RPM limit table. In this case I have put 16,000rpm limit at 100'. This is the temp I am running, more or less, and that it where it seems to be limiting, even with RPM limiting disabled.

Is there something else which enables RPM limiting and why does it indicate a rich AFR? With either ignition cut or fuel cut it should indicate a lean AFR(more oxygen), surely? As a workaround I'll set the rpm limit to 18,000rpm across the board.

I have a small intake plenum which the turbo fed. It has a reasonably small inlet. I left it on after I removed the turbo to lessen the risk of something going down the intakes. This resulted in the red line on the graph below. I had to increase the fuel a bit. Chasing the rpm limit and eliminating possible causes I removed the plenum. This made it lean and required about 30-50% bigger numbers in the fuel map. This resulted in the blue line. The green line is with the turbo fitted and running about .4bar boost.

Slowly getting there but I really want to be able to fully rev this thing, that's why I built it.

 

fuel table.PNG

PIC_1877.JPG

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Can you do a PC Log of a run?  https://www.youtube.com/watch?v=_P1LRANeO4A

It doesnt sound like a limit issue because as you say it would typically go instantly lean if there is a misfire/cut.  You can look at the parameters "Percentage Fcut" and "Percentage Icut" to see if any limiters are being applied.

If its going rich I would be leaning more towards airflow - VE falling away.  Maybe valve bounce or one of the manifolds are starting to choke it?

ozQzAb5.png

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I have noticed the "Engine Speed (RPM) Trigger Data flash yellow when the problem happens. I took this to indicate that a limit was being reached in the ECU. The throttle bodies are the same size as the original CV carbs so airflow shouldn't be a problem. When I removed the plenum it obviously improved airflow but the rpm limit remained the same. Valve bounce has been suggested but the engine revved cleanly with the carbs and GSXR250 ignition. I am going to try editing the rpm limit table to 18,000rpm in every cell. It is obviously having some effect as it indicates an RPM limit, as below at 7000. In my case it was 12,000. I changed the associated table entry to 18,000rpm then disabled RPM limiting. the RPM Limit was now 18,000rpm

image.png.fa8551bcacd263daf8373574dd8b68bf.png

image.png

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4 minutes ago, Speedpro said:

I have noticed the "Engine Speed (RPM) Trigger Data flash yellow when the problem happens. I took this to indicate that a limit was being reached in the ECU.

No this does not mean a limit is being reached, you can set whatever value you want a parameter to change colour at as a warning.  This is a warning system only - for instance you might want ECT to turn red when the water temp goes above 100°C so the tuners attention is drawn to it.  There are separate settings for orange and red warnings.

 

10 minutes ago, Speedpro said:

It is obviously having some effect as it indicates an RPM limit, as below at 7000.

It will always display what is in the table, but if the rev limit is set to off then there will be no cuts applied.  Only when the RPM Limit status says "active" is a limit being applied.  As I said earlier the correct way to see if there is a cut being applied is to view or log the "percentage cut parameters" - as looking at RPM limit parameter alone is only a small part of the picture - it could be something else you didnt consider such as gear cut, boost cut, traction control, launch control, voltage cut, etc...

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I'm still waiting for parts to make a spring tester. I want to compare my spare head valve seat pressure versus the head on the bike. I'm trying to avoid dismantling the engine.

Apart from that I have measured the current draw when running the engine. Surprisingly it ramps up as revs rise. I haven't tried it on the dyno yet but it looks like the current draw is going to be more than even a Lithium battery is going to supply for a reasonable time. which means I'm going to have to remove the 6-tooth trigger disc off the crank and refit the generator rotor. The generator rotor only has 4 teeth on it, one of which is much longer than the other 3. All 4 trailing edges line up so my question is, what edge is the important one, leading or trailing, and will the longer tooth cause any problems.

Link told me at the start to use a 6-tooth disc but with the current draw I need to generate electricity. It's either refit the alternator rotor and use it's trigger arrangement or fabricate a remote mounted alternator.

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yes

The rotor is off the original 4 cylinder motor. I presume the longer tooth on the rotor identified which pair of cylinders was where. As suggested by Link i fitted a 1-tooth disc to one cam and a 6 tooth disc to the crank. A mate has fitted a multi-tooth piece to a rotor on his bike but his engine has more space for pickups and is never going to rev as hard as I hope to get this one going. I'm only thinking of putting the rotor back on as I'm pretty sure I will need an electricity supply

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What type of sensors does this original rotor use - are they two wire (reluctor) or 3 wire (hall/optical)?  If it is reluctor then all teeth would need to be the same "length", it it is hall then the one long tooth will be fine as long as 1 edge of each tooth is evenly spaced.

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Original bike sensor is a 2 wire reluctor. Due to the amount of work to change the tooth length and rebalance the rotor, or to add a 2nd ring of teeth with 6 even size teeth I decided to give it a go with the stock rotor and the 4 teeth, 1 of which is longer. All trailing edges are separated by 90'. After setting the base timing to 0' by simply spinning the engine by hand and adjusting the base timing to get the marks to line up, I put the plugs back in, fitted the fuel pump fuse, and gave the back wheel a pull in 3rd gear. It fired up first time and runs just sweet. Warms up like normal, blips like normal, and just on the stands is happy up to 15,000rpm.

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Yes, it will run, but with a reluctor sensor, the ECU triggers at exactly the centre of each tooth.  That means the long tooth is going to be seen by the ECU as offset by approx half the length difference.  i.e. if the long tooth is 10 degrees longer than the others the ECU will see that tooth 5 deg earlier than expected.  

This will likely cause significant spark scatter at certain RPM's and poor dwell control.

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I expect this problem will only effect one cylinder so will carefully mark the rotor in 2 locations and look for a difference when running.

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