It is racetime now. Thank you for your help, Marcell.

Thematical template: cleanup this page by moving info to related page

Overview and some other info will remain on this page.

Injector settings Keihin 0660 52219 FBBJF Still no fuel flowrate info ??

means you inject every 8th event (*next trigger tooth=3); every 4th crankrot, that CANNOT BE right !

The multiple should be 4 (or 2, depending on how you tuned earlier):

means you inject every 4th event, every 2nd crankrot (usual practice, but maybe not in this case) means you inject every 2nd event, once every crankrot (was tuned with inj every crankrot if I understood on phone)

Thematical = good; Chronological = bad

Despite large amount of work building the vehicle...

Some factors contributing to last hour mess, and missing the race by a few minutes:

[see first part of vemslog]

Trigger is the most important signal of the system; but the decisions related to trigger HW were disastrous from the beginning

Firing once per crankrot because no camsync?

Validate shows "a bit too many" warnings, you never listed them to confirm !

1 cyl motorcycle engine... UPDATE:

proper 6-1 configuration (for ignch6, ignch5, ignch6, ignch5 ; reference teeth 0 3 0 3) is pending, Only ignch6 drives real igncoil

  • no strobe, no scope on the racing site, only DVM and notebooks

Pretending 4 cyl engine, but only 1 ignout actually actuated, once per crankrot desired

REFTOOTH (with next trigger tooth=3 : another_trigger_tooth=03

h[1]=00 03 00 03 ... seems right.

but the configured ignouts seem bogus:

h[2]=60 50 40 40 40 50 60 70

Ignouts to be configured if you want ignch6 to be actuated once every crankrot:


We are have a problem, because the tooth which we had glued on, had come down, so we had cut down 4 tooth, to make a 6-1 type flywheel of it. After changing the settings in VT, it is not working. On the triggerlog, it can be seen, that the signal remained as the original 12-3 flywheel. Here's the triggerlog:




DATE: 09.01

Adjusting the NR of cyl solution worked: RPM shows ~500rpm (reliable, real value). Captured some triggerlogs, but unfortunately, I did not managed to make vemslog, because I had to restart vems, to restart the motorblock, when with the 1-cyl setting, we reached "10000 rpm" (not real RPM) and VEMS ECU automatically applied sparkcut (redshift, as configured).

So here are the triggerlogs:

Additional: we "idled" the engine, first we saw flames in the exhaust, after that we idled at about 2000-2500 RPM, and noticed after 2 minutes, that the exhaust tube is glowing right under the outtake (?), so immediately stopped the engine. ATDC spark ? Perhaps together with excess fuel ? With some other anomaly maybe ? Unintentional "ALS" ?

Did you verify spark position with strobe ? Annotated vemslog with your manual notes about strobed sparkangle (compared to gauges) would be good.

Here's the triggerlog:

Thank you for your support,


DATE: 08.30 Vems Support.

I Have reviewed your triggerlogs and vemscfg, intresting; it seems your rpm shows ~5x real rpm.

Try to change the following:

Please supply a vemslog of cranking and engine running with setting at 1, than another vemslog of cranking and engine running with 2. make sure to power cycle the ecu between setting changes

Best regards, Dave

DATE: 08.29.

So far I have managed to wire up the two temperature sensors (CLT, MAT), these are under calibration. Also wired up the MAP sensor, and tuned it a little bit. And after all that work, we have managed to start the engine (after fuel system egy cooling system setup of course). And a new problem just came up: the CKP sensor (VR type), which shows us an appr. 833 rpm cranking speed, and after start it is 5000-6000(!!)rpm. We do not know it yet, I made some triggerlogs of the problem, I would appreciate, if someone would see them.

Of course the idle speed is not stable, and almost impossible to make it though in this condition. So what do you think of it?

Here are the vemscfg, triggerlog, vemslog (intereseting part is from 405:30) files:

DATE: 08.25.

We had a problem, that the 1.2.31 software, which is working on our VEMS 3.6 is not supporting the N-3 missing tooth, which is the stock layout in our Honda CBR250R motorblock. Managed to solve it in an unique way: after we measured the distance between the tooth, we had created a NEW TOOTH from steel, and glued it on with super strong glue.


After testing in VEMS triggerlog by cranking, it works like a charm, I hope, it will in the future too.

So after some cranking, we managed to find out the right TDP with a strobe, which is: FTT=3 and TDP=41,5 deg, and the spark angle compensation is 0 deg.

The next tasks are:

Primary trigger 12-3

It turned out crankshaft position sensor (CKP) is 12-3 type from factory (this is a motorcycle engine). (is it on crankshaft, not camshaft ?)

EDIT: I have watched this page: MembersPage/AutoVeltiosis , and here the guy solved his 12-3 type with downgrading to 1.0.X the VEMS firmware. I started the firmware update wizard in VT, and found the there is an 1.0.80 firmware.

Downgrade to 1.0.x not recommended.

The 360/11 deg tooth with would need some bench testing. Alternatively a small (heatshrink hidden) arduino adapter could made a 6-2 from the 12-3, by allowing through the following pulses (0 is the tooth after the missing tooth): 0, 2, 4, 6 (filtering out 8, and all odd numbered pulses).

Date: 12 august

So I am going to write down all the information, I collected so far, using my notes.

Parts, we have already ordered from vems shop:

VEMS pinout in table (hungarian)


COP pinout:

(normally pin2 and pin4 are joined)


And finally, our options, when ordered VEMS ECU:

Question Nr.1: I heard, that some injector require dashed signal, some require continous signal from ECU. How do I know, which is correct in our case?

Question Nr.2: Which type of diode should be used with the relays?

Preparing VEMS v3.x install;


So now we are on the way, to build up our bike. Some VEMS parts like EC connectors, WBO2 (LSU4.9) sensor and some relays had arrived. have already tested the TPS and IAT sensors with DMM, also tested the IACV, which is a 4pin stepper motor (R=110 Ohm).

Successfully bought a Coil On Plug transformator, which fits well to the engine block.

We are also planning to use a Mechatromotive Racing LCD, which communicates through AIM with VEMS.

Question nr.1: measured the resistance between the 2 CKP sensor outputs, the resistance is the same in both direction, 236 Ohm, so it is a VR type. Please, confirm, if I think well.

Other questions, not very important, only for future improvements:

So the questions are:

I would like to use oil temperature and oil pressure sensors:

I found these ones suitable (for pressure):

(I need only one of them)

For temperature, what do you prefer/offer?

I am thinking about using a VW Bora 1.8T ignition transformer (stock number: 715459 0040102043), but I need a 10mm shorter one.

Do you think is it okay to use this on a motobike engine or use some CDI driver? Or what do you recommend?


VEMS supports shiftcut, yes. Input can be shared with launch, or separate (or when launch is not used => of course "separate").

We are building a custom bike, with a Honda CBR250R (2015) engine (1 cyl, 250ccm).

1-wire interface not needed
EGT-input (exhaust gas-temp. input)maybe yes, but not essential
ETC BridgeOutput? Interface no need, we have manual gas control (with bowden)
Flyback type still do not have certain information, just the type of the injector (Keihin 0660 52219 FBBJF). Still no DVM to measure resistance ?
Hi-side PFET outputs no
Ignition driver yes, 2+6 (cost-effective and the most suitable for one cylinder)
Knock input channels no
LCD connection yes
MAP connection offboard. We have a Keihin sensor unit (with 5-pin connector) for that, still don't have a datasheet, just serial numbers: 5318A (includes MAP sensor, IAT sensor, TP sensor)
Mounting-styleflanged case is good
Primary trigger VR (I have found the stock trigger as inductive, then it is suitable, isn't it?) 12 toothplaces, 3 missing
Secondary trigger no, we don't have camshaft position sensor
Special request now, we have just initial questions, so we have not got any request
With SD card "removable" is removable, to plug in another card in 3 sec, or for quicker download data to PC