Multiple VR senors on a motorcycle

mainlylinux · Post by **mainlylinux** » Fri Apr 21, 2006 5:53 am

Hi guys - I have a motorcycle (4 cylinder) with 2 coils in a wasted spark configuration. Each coil fires based on a signal from it's own VR sensor - the 2 VR's are 180 degrees apart and the crank has a single tooth wheel on it that causes the trigger as it passes each of the VR's.

Right now I have megasquirt running by taking a signal off of one of the coils and telling megasquirt that the bike is a 2 cylinder.

With the MSnS-extra is there a way to input both VR's and switch megasquirt back to a 4 cylinder engine? Eventually I'd like to have a wasted spark arrangement that the megasquirt can control.

I've done searches thru the forum for things like "multiple vr" or "dual vr" but I'm not getting any hits that make sense to me...

Thanks in advance for help,

Dan

Jim · Post by **Jim** » Fri Apr 21, 2006 5:24 pm

Is the Wheel removeable , or is it machined into the Crank ?

...................Jim

mainlylinux · Post by **mainlylinux** » Fri Apr 21, 2006 9:40 pm

It's removable - I'll post a picture of it.

Dan

Jim · Post by **Jim** » Sat Apr 22, 2006 3:20 am

Answer Me another question ,

Does your engine have a separate "Magneto" coil to drive the Ignition Coils ?

or only Alternator windings to charge the battery with ?

is there a way to input both VR's and switch megasquirt back to a 4 cylinder engine?

Yes , with a simple external curcuit that would "add" both coil outputs together .

Problem is , MS wouldn't have any way of telling which coil should be fired .

Since you say the Wheel is removeable , the best solution I can devise is to
have a machine shop make you a wheel with 36 teeth and one tooth removed ,
this is refered to as a 36 minus 1 or 36-1 wheel , MS can "decode" this wheel and
figure out when to fire which coil , however I don't recommend this if you are
new to MS , but there is another alternative , a Ford EDIS Ignition Module ,
it uses the same 36-1 wheel and is bullet proof and easy to connect to MS ,
it will also directly drive your Ignition Coils , provided that they run on 12 volts .

The EDIS Ignition Module is availible cheap in almost any junkyard ,
and is well documented on the MS web site .

Using the EDIS is also a bonus because it keeps you from having to run wires
directly from your Coils into the MS box ,
this keeps the trashy spikes from you Coils away from the delicate electronics inside MS .

The EDIS Module is very compact and abuse proof ,
it's about 3.5 x 2.5 x .5 inches , see the attached JPG .

...................Jim

Post by **jsmcortina** » Sat Apr 22, 2006 4:47 am

The dual VR sensor setup will be supported in the up-and-coming MicroSquirt. Another alternative with the existing MS1/Extra code is to make a 4-1 wheel (teeth at 12o'clock, 3o'clock and 6o'clock) and use the wheel decoder and direct coil control.
Or, the EDIS if you have space for a 36-1 wheel.

I did try to support dual VR sensors in the Extra code and almost got it working a few years back... but it wasn't stable enough, so I aborted my work.

James

mainlylinux · Post by **mainlylinux** » Tue Apr 25, 2006 2:11 pm

James, when you almost got the dual vr code working, how close was it? what code will be used in the microsquirt?

Dan