KTM LC8 engine. 4-stroke, 75-degree V2, odd-fire. 950/990cc
EFI version has 24-2 crank trigger. No camshaft sensor.
TDC info needed (here)
It`s hill-climb motorcycle and race is very soon!
- Maybe you can dig up the exact timing info even sooner (that's considered the discussion starting point : "I'd like to set up timing for the 2 cyl, TDC-s are at ..., ... degrees after tooth0 (tooth0 is the first tooth after the 24-2 missing gap)".
- Maybe there is a crankshaft on the shelf, that could be measured, (even if info found: verification is good) 75 deg + offset crank ...
[KTM LC8 engine repair manual]
Special trigger tooth reference table ?
- it's possible to set up with per cyl spark delay (and evenly placed reftooth) and get it running (see below)
- when the TDC info is clearly published here (also: how it was acquired and verified), perhaps some more refined, even better (more precise) approach could be provided for smoother startup (not a big difference with running engine, but could help cranking when angular-velocity variations are more significant).
Hello Elbe,
Please create a sharing report containing your current config (vemscfg) and triggerlog of engine cranking 8-10 seconds without ignition and injection fuse and i'll take a look at what is required to get it working.
Best regards Vems Dave
Thanks! I will do it tomorrow.
I found shorter triggerlog file:
http://www.vems.hu/files/ElbeEngineering/KTM_lc8_24minus2.triggerlog
Config:
http://www.vems.hu/files/ElbeEngineering/Config_KTM_LC8.vemscfg
Dave, was it helpful or I have to get longer trigger log?
Hello Elbe
Sorry i missed your edit (it helps if you provide a bit more text in the summary of change box so it stands out, just "edit" is easily missed)
According to my review the engine should be able to run without any firmware mods; the longer triggerlog without IGN and INJ fuse should provide a bit more info on this, please keep spark plugs in the engine so i can see compression phases also.
Review of triggerlog KTM_lc8_24minus2.triggerlog:
- 24 minus 2 correct
- odd fire engine with tdc at around tooth 14 and tooth 19
- rotation period around 180 msec for 360 degree
- tdc time diff 232, 150, 236, 149 msec (roughly)
- this translates to 220, 140, 220, 140 tdc crank degrees offsets (roughly)
- it seems you might get away with delaying the second ign index using the spark delay function in base setup -> cyl separated spark delay, around 45 deg should do it.
If you run into any trouble please let me know and supply new triggerlog + vemslog; I'll review and provide hints on how to proceed.
Best regards, Dave
Thanks!
Is this error normal? I can try these settings on bike in one hour.
Reference tooth:
0 - 14
1 - 19
Next trigger tooth = 19 (is it correct?)
Next trigger tooth = 3 Marcell thinks would sound better, see below
Hello Elbe,
It seems you misunderstood my instructions, do not adjust anything from "Config_KTM_LC8.vemscfg" so start from your original config and only change delaying the second ign index using the spark delay function in base setup -> cyl separated spark delay, around 45 deg
Best regards, Dave
Dave, I need cylinder separated delay approx 75-degrees. At the moment 63.75 is maximum (63.75 degrees of delay is close but not enough: actually more than enough with good strategy). Otherwise it should work.
Marcell's A x x B x x x x next_trigger tooth=3 proposal (assuming near 135..140 and 220..225 degrees between events):
- 135 deg (=3*3 tooth)
- and 225 deg(= 5*3 tooth)
- looks like best possible approximation for this engine
- I would start with next_trigger tooth=3 (No camshaft sensor. anyway).
- Will only require some very minor per cyl spark adjustment (around 5 deg, or perhaps less; perfect cranking behavior and precise timing without compensation-tweaks even for extreme angular accelerations )
- NO special reftooth at all, completely evenly placed !
- you just set 6 of the 8 cyl to dummy ignouts where no ignition transformers are connected: A x x B x x x x (rotated if necessary, of course)
- (the next_trigger tooth=3 => 8 events per crankrot resemble "8 cyl 2 stroke"). The ECU can most easily and precisely fire to near any of the N*45 deg points (regardless if valves are actually 2 or 4 stroke: keep 4 stroke setting not 2; if there is such).
- IIRC some other V2 motorbike was setup similarly earlier, with only 2 properly selected ignout out of 8 (Harley Davidson, maybe)
Thanks!
I tried settings like this:
Triggerlog: http://www.vems.hu/files/ElbeEngineering/v3.3_u010090-2015-06-12-12.56.39.triggerlog
I see 300-700 revs when cranking
Hello Elbe,
I made an updated config based on Marcell's recommendations for you, please upload this to your ecu.
This should result in a triggerlog looking like this:
- event IGN0/1 (green) are the dummy events (select unwired outputs for those)
- your real events should be in IGN2/3 (red/purple) fill your used ignition outputs there.
As you see they line up with ktm lc8 v3 tdc quite nicely, use spark delay to correct the minor offset if needed.
If you run into any trouble provide vemscfg (not screenshots) and triggerlog and i'll review and make suggestions.
Best regards, Dave
Thanks! Seems it`s working. What about injector settings? Same as in your config?
Yes those should be good, divider = 4 means 1 injection per injector per 2 crank revelations normal for a 4 stroke engine (divider = 4 because of the cheated higher cylinder number).
Best regards, Dave