Sachse Ignition

Hi jotacorsa,
                  No, its because of the extra sparks that I am getting.

I have checked and checked and checked again, something is causing it to spark when it shouldn't.  :(
 
Didn't someone earlier suggest the coils might have got fried with the reverse voltage?
Could you try to source different coils? TEK coils cheap on Ebay for example.
If it's not the pick ups or the black box then the coils must be investigated, no?
 
Just a thought - reversed battery connections may have damaged the reg/rect which could mean you've got AC firing around your wiring.  Did any fuses blow at the time?
 
Good point. Really there are few other options to check.
If all the connections are good and no wiring has melted then each of the components (coils, r/r, black box) need to be eliminated from enquiries.
 
Hi Guys,
              Thanks for your thoughts, I have checked the coils with a multi meter and they seem to measure up and as the coils are producing sparks so I guess they are working.

No fuses blown, no wiring melted,  at the moment I have the R/R disconnected and the alternator is hanging by it's wiring.

I had Marco test the R/R as I thought that might be fried as well but he says it's fine.

 
So, to recap, the bike ran well before the battery incident?
But now it 'double sparks' and refuses to fire?
And you have tried new triggers and black box? And had yours tested and found to be ok?
Sounds a very strange one.

If all else is checked and found to be ok then begin to try the improbable.

Case in point, my bike refused to run on all cylinders at the same time since winter lay up.
Stripped and ultrasonic cleaned the carbs 3 times
Did find crap/oxidation in them, but then in a fit of lateral thinking I changed the plugs and it ran perfectly on all cylinders.
Fouled plugs...
 
Just caught up on this thread do you have a hall effect trigger card or an optical trigger if you are sure how to pick the difference the optical one has a rotor that cuts between an optical sensor,
If it is optical it is not uncommon to get a stray light spark PRIOR TO THE ACTUAL TIMED SPARK THAT WILL HAPPEN AS THE OPTICAL CUTTER JUST BREAKS THAT LIGHT BEAM.
i agree with Keith swap the low  tension coil wires if you belive you have it timed correctly.
 
actually Maurice has a point, is your system using the earlier Optical trigger board ?
if so it is affected by light sources so you need to install the timing cover before trying to start the bike so it is in a dark environment
 
if I read all you have done is it possible you have an issue with the rotor itself. Why reverse polarity would have done anything can't fathom but if the box has been tested and thrn replaced along with the board then it's the rotor that tells then what to do.
So worth checking it or even swapping it out at least if bought else to rule it out.

What was wrong with the original battery by the by just died due to end of life or did it fail cause of an issue
Again I struggling to come up with what reverse polarity for a few seconds st most would have done here
See it a lot on the field sometimes might take out an ECU but most times it doesn't and would be rare indeed to see wiring fried from it
Say just something out of left field take it the starter is spinning the engine in the right direction??




 
Hi Guys,
            Thanks for your replies.
Battery was just at end of life.
I was beginning to think that it might be something to do with the Rotor, but it is just a Aluminium ring with two magnets in it and can't see how that would produce the 'extra' sparks.
I am turning the engine over by hand, but the starter motor is turning the engine in the right direction.
I have timed it with a Piston Stop Tool and Degree wheel.
Yes Grant, you are right with that one, very strange.

 
Strange indeed. When you connected the battery the wrong way round, the windings of the alternator coils have been powered up via the R/R unit, converting them into powerful electromagnets with heaps of Amps going through them. That has been the sparking you have observed while connecting the battery with reverse polarity.

The massive magnetic spike created by the alternator coils could have, at least in theory, affected the magnetic rotor of the ignition trigger, if we are talking about mk1 triples, but I do not see this happen on an mk2 with the alternator sitting far away from the ignition rotor.

Once you had finally released the battery cable, the collapsing magnetic field of the alternator coils caused a massive voltage spike towards the R/R. In worst case this voltage spike passed the R/R just being converted to a positive voltage spike, now running towards the negative of a battery, which is disconnected at its positive, so no relief found here. Hard to tell where he energy of that voltage spike has been dissipated finally, could be anything upwards the + connection of the R/R.




 
I am at a loss to know what to do, this has been going on for too long and I am no nearer finding out what the problem is.

I have two boxes and I get the same results with both of them, I have a new trigger board as I found that the earth wire close to the box had got damaged, it broke off just inside the sleeve.

I have tested the Coils and get readings close to the Dyna specs, the double coil has no polarity so wires can be on either way and the single has a red dot on the positive, so not wired incorrectly.

It seems to be related to when the L.E.D's come on and is sending a false signal to the coils, ?

 
Sounds like you've disturbed quite a bit of wiring to remove box; trigger board; alternator and anything else along the way.  I'm not familiar with Sasche systems but it's the easiest thing in the world to disturb a connection (like your damaged earth wire) or make a mistake when reconnecting.  Can only suggest you carefully check each and every connection in turn.  You'll likely kick yourself when you find it.  On RGS wiring it's easy to swap one of the smaller battery connections for example...
 
Can you check continuity of each wire leading from the triggers/alternator area to the r/r and black box?
Maybe something melted and shorted? Just a long shot.
You have checked all the obvious suspects so time to think laterally.
 
Willz900 said:
I have two boxes and I get the same results with both of them, I have a new trigger board as I found that the earth wire close to the box had got damaged, it broke off just inside the sleeve.
Click to expand...

common problem with the Sachse set up, brown wire is terminated to the outer sheath of the wire bundle cable and seems to be quite fragile

Willz900 said:
I have tested the Coils and get readings close to the Dyna specs, the double coil has no polarity so wires can be on either way and the single has a red dot on the positive, so not wired incorrectly.
Click to expand...

that is actually not correct, both coils have the same pole as positive, compare where the single coil positive pole is and the dual is exactly the same, it is just missing its red dot

Willz900 said:
It seems to be related to when the L.E.D's come on and is sending a false signal to the coils, ?
Click to expand...

so you said a couple of posts ago that you have the magnetic trigger set up so we can cross off bright lights effecting the optical triggers

way the Sachse system works which is exactly the same as the systems that we make ourselves work, the hall effect trigger is a switch and needs to be turned off and on which is what the magnets in the rotor do
as you rotate the engine in the correct direction of rotation, as the South pole magnet passes the trigger it turns the trigger on, that is when the LED light will come on next to that particular trigger. South pole magnet is marked by a "S" stamping on the face of the rotor

when the "N" being North pole magnet passes the trigger it switches the trigger off and the LED light will also go off
LED lights have nothing to do with what is happening apart from showing you that the triggers are off or on at any particular point of rotation

I will send you an email and get you to send me some photos of your set up to see if I can see what the issue is, doubt I will see anything but you never know
this is a very odd problem as you have said you have tried 2 different boards and 2 different boxes with the same result
most odd

You didn't remove the magnetic rotor and install it back to front did you ?
not even certain if the system would work if it was on back to front




 
I know nothing about the Sache black box, but the symptoms sound exactly as those on my Ignitech when it magically changed from the "customised" setting to some other bum fuck setting. Ran on one and farted and backfired like crazy with poor spark.

I wonder if this could have happened during to reverse polarity mistake.
 
I know nothing but keep thinking about your comment earlier in the thread :-
"The bike turns over, but back fires all over the place."

That is exactly what it will do when triggers timed arse about which i am sure you know.
I also know Keith had already said to reverse the Lt wires to coils (easiest way to just swap em at the box) and you confirmed you had done this.
Did this change the way the bike tried to fire at all?

Just thought I'd throw this out there again........................ 
 
I have a Beemer booked in next week for installation a Sachse ignition system (among other things). After reading this thread I'm beginning to dread the prospect.

In regard to a weak spark happening when the LED comes on, I don't think that's significant. All that's happening is the coil being energised in preparation for the actual sparking event (which happens when the coil switches off). During the coil energising phase there will be some voltage induced in the secondary side of the coil as primary voltage ramps up, which may produce a weak spark.  But a weak spark during the coil energising phase would be at around 100 deg or more BTDC and way too advanced to affect combustion.

If you're getting a healthy spark when the LED goes out, it would seem that your ignition system is working OK. You're getting backfire so fuel is apparently getting into the cylinders. Even if the carbs are way out of tune, the engine should still kick over and at least try to start. So pretty much the only thing left that could be wrong is ignition timing. If nothing has changed mechanically and the LED is going off somewhere near TDC, then the plugs must be firing on the wrong stroke. As others have said - swap the primary leads between the 2 coils.
 
What voltage is at the battery as you crank the engine over?
I think the Sachse needs a certain voltage before it will fire.
Think it's 9V or thereabouts.
 
If it all worked fine before he accidentally reversed the battery polarity then I'd say something is terminally fried...


Had this problem on my T160 once: fried the main (irreplaceable Motorola) transistor in the ignition box: went back to points...


just my 2c
 
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