MicroSquirt.com read only forum (Jan.15,2018)

g'day, just purchased the latest microsquirt,

and i'm just after some information as the latest stuff on the ex250 dates back to 2009.

i've got a 1995 kawasaki zzr250 (ex250-h4) and from what i understand the microsquirt might have a alittle trouble with the crank position sensor,

is the problem still present in the latest model of the microsquirt, or has it been fixed to incorporate more motorbike models and sensors.

any info would be appreciated

What trigger pattern do you have on the stock crank trigger?

3 small 1 large,

same as the other post i found on here, but its been a few years since that post and just wondering if there is still a problem with it or has the firmware for the microsquirt been upgraded to work its way around that problem.

Unfortunately, it's a hardware problem. The VR circuits are zero-crossing detectors, but the long tooth can trigger a 'zero-crossing' signal over a fairly wide region. The FZR600 trigger pattern is very similar to that found on your bike, with 3 short (5*) teeth and 1 long (36*) tooth. The short teeth give good clean repeatable signals, but the long tooth can trigger anywhere over a 30* range. It can't be predicted, it can't be duplicated from rev to rev, and it can't be worked around, so it completely screws up the timing.

There IS a pre-filter add-on circuit for use with a code patch for the MS2/Extra code, but that patch hasn't been adopted / approved by the developers. Basically, every time you want to update your firmware, you need to modify the new source code with the patch, then compile it.

i've been thinking on this alot,

i was wondering if at all possible to use the zzr250's cdi module, as it has the firing pattern locked in.

run the crank sensor into the cdi like normal and then cdi into the microsquirt via the crank sensor wire,
the cdi should convert the signal into specific pulses that the microsquirt could understand..

have no idea if it would work or not, and dont have the knowledge nor the money (Already at limit) to get more parts to add onto the unit.

http://www.useasydocs.com/details/coiltrig.htm

seems i can use the cdi's tach output to do whats needs, since im not using the controller to change the timing, just using it for the throttle bodies and fuel.

another question, this one is alittle far out there.

on the ignition circut for the ex250H, it shows the tach signal out on the CDI is split one wire goes to the tach, the other goes to the ignition coil, which this bike uses a wasted spark setup.

since there is no way around this, i have to use the wire that goes to the tach for the signal for the microsquirt, i also have the thought that the microsquirt has ign 1 and ign 2, since the cdi is sending the same signal for the tach and the ignition coil, and the ecu could accept the input for the tach/ignition would it be at all possible to run the ignition from the microsquirt via ign1 and 2 with that one signal from the cdi.

would be nice to be able to run the ignition coils off the microsquirt this way if its at all possible, i doubt i will damage the ecu or the engine by trying it but if anyone on here could shed some light on this would be appreciated.

I'm fairly certain the Extra code's 'Twin trigger' could use this; disconnect the Kawi TCI box from the coils, connect the coil output leads to the VR1- and Vr2- wires on the uS, each with 1k pull-up resistors to 12v. This will give you a nice, sharp square-wave trigger. I *think* the B&G standard code 'Dual Spark' would work in a similar manner, using line 1a on the chart.

The problem I see is that the Kawi box is going to be advancing and retarding the spark according to the rpm, so most of your ignition timing is going to be +/- a relatively few degrees of some fixed value. If you declare that the trigger offset is 20deg (for example), most of your 100% row is going to be 0, perhaps a few cells in the 18-22 range. Where you'll have some ability to play is in the lower rows, where you can increase the spark advance under light load (measured by MAP or TPS).

Did that make sense?

first part sorta, second part strangely enough yes.

i'll skip using the microsquirt to judge timing for the time being i know it will be alittle over my head to add in resistors just yet., though i will need the tacho wire for the microsquirt to control fuel.

so using the tacho wire on the optoin+ and using a 12v supply for the optoin- (or would it be better to ground the wire?), but leaving the coil in wire attached, should give me what i need to get the fuel working, thats if i'm reading it correctly from the info i've found.

so the way it is now tacho out on cdi --tacho to tacho out on cdi --- microsquirt --- tacho
--coil in --- coil in

should get atleast the fuel to run without timing and without messing around more then that?