http://thekneeslider.com/jj2s-x4-500cc-2-stroke-update/
http://jjsdesign.net/motocyklstudialny/
500 4 2T - Very interesting but I won't be trying to make a Bucket Racing version.
Off to the foundry tomorrow
Sleeve with piston. Sleeve ready for nitriding.
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To nights effort was about trying to figure out if I have the right size injectors and if I can make them do the job in less than 360 deg at max rpm.
Selected two points on the Alpha-N, TPS/RPM Load map and checked the screen gauges at 11,750 and 12,500 rpm.
Now FUELPW1 and FUELPW2 on my setup are different size injectors and don't have to have the same ms pulse width.
But I do expect that for two different RPM's with the same load (ie Alpha-N TPS Load/rpm map number 135.023 at 11,750 and 12,500) an injector would have the same pulse width.
5ms at 11,703rpm = 351 degrees and for the same load at 12,500 rpm I would expect the pulse width to be the same.
But here the pulse width has decreased as the rpm went up and 4.8ms at 12,500rpm = 360 degrees. This indicates that the injectors have maxed out and need to be bigger.
Increasing the number two injector from 330 g/min to 500 did the trick.
The next trick is to increase the minimum off time between injection pulses. This is used to force the cross over between 1 to 2 and then 2 + 1 and to try and get everything done in less than 360 deg, or as quickly as possible, ie 180 - 240 degrees or so without cutting things to short for the injectors to get it all done at the higher rpm. Basically, the injector has to be on for at least 2ms and not more than 360 deg, so as the rpm goes up the window gets very small. Next time I might try a dummy map with a straight line just to make it easier.
The whole thing is a bit of a fine balancing act.
As if these options were not enough already, are you able to vary the fuel pressure, too, TZ?
Yes I know, much more complicated than I first thought but makes sense as I get used to it. I guess I could vary the fuel pressure and I think there might be a map for doing that but the basic kit I have only has a simple pressure regulator. I will have to look into the possibilities of varying the fuel pressure, thanks for the tip.
Foundry day successful.
From glue, beads and bodifill rubbish, to somthing usefull.
Things that you don't read in the Ecotrons manual but now we know for sure.
ECU case is electrically isolated.
ProCal software is connected and running.
ECU case is earthed.
ProCal software is dis-connected and has stopped running.
The metal Ecotrons ECU case can't be grounded in any way when mounted to the bikes chassis, next time I will get the cheaper plastic case version and fit my own RF shielding.
. . . . and there will be 7mA of so flowing to ground. There was on mine.
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