BTZ wiring help needed

Spondonrider

Spondonrider

Hero member
Location
Colorado
Damn, a guy drops out for a bit and stops paying attention to you nutters and all hell breaks loose...well I'm glad you all seem to have worked out a new home while I was gone cause I'm out here in the shop, in the middle of the night, listening to some King Crimson (Islands) while working on my 1981 Jota with the series 2 180 in it. Seems my IIS ignition has bit the big one, gone to the big electrical scrap yard in the sky as it were. As an interim solution (loving the trumpet playing on Islands....) I'm trying to reinstall my old BTZ ignition. Its been so long since I've fooled with one of these I'm having a hell of a time sussing out the wiring. I have the harness in the bike and the ignition modules are hooked up...actually they were never removed so that part was easy. What I'm trying to figure out is the wiring to the coils. I have a wiring diagram but the color codes don't seem right. From the ignition harness I have 2 unused wires. One is red and black, the other is orange and black. Are these triggers for the coils and if so which one goes to which coil? What about grounding for the coils? Any help here appreciated, I'd love to get this thing running for some last rides this fall...would be the only rides since last summer (2009) so really, I need to get this thing back on the road and my life back in order!!!
Thanks for any help!

Ed
 
Hi Ed, in theory red/black goes to black wire of single-output coil and orange/black to black wire of twin coil.  These are the switched grounds for the coils (switched by the BTZ boxes).  The orange and green wires from the single and twin coils respectively go to the ballast resistors, the other ends of the ballasts go via the chocolate block to the BTZ box red leads in one direction, and to the orange/white lead from the kill switch in the other direction.  Basically orange/white from the kill switch provides B+ to ballasts and to BTZ red leads via piggy-backs at the ballasts.

Hope this helps, sorry but don't have this setup any more so can't send any photos.
 
Thanks Nick!
I forgot about the ballasts, not sure I have those any more. Anyone who could send me a picture of the coil/ballast resister area I'd be grateful! I'd just like to see how it was originally set up.

Off to the parts bins to look for a couple of ballast resisters...


 
Hi Ed, the ballasts are fixed by small cheese-heads to a couple of little angled brackets, just astern of the coils - well, on my older triple they were.  The coloured leads from the original coils then run to them quite nicely.  If you are using more modern coils like the TEK ones you might just not bother with the ballasts, just run from the kill switch to each coil and to the chocolate block for the BTZ red wires as a suggestion.

Sounds like you are nearly there - King Crimson has got to help!
 
Hi Again!  Just saw your latest, I don't think a lack of ballasts will affect the BTZ boxes much although the coil charging current switched by the BTZ will be a little higher.  Maybe someone else has experience one way or the other?
 
Ed,
Forget the ballast resistors, not needed, wire direct to your coils.

Do you know what is wrong with your IIS.?
I have a few IIS systems at home I'm holding for spares including a Series 2 x 180.
Is it the trigger plate or the control box.?
Does the system power up for example.?
Will it enter test mode successfully.?

One other thing you need to check as well.
See how strong your magnet is in the rotor, try and see if it will pick up a small screwdriver for example.
Magnets get affected by the heat and lose their strength which stops the ignition system from working.

HTH
Red

 
removing the balast resistors is something that a lot of people do, but remember that your coils will run at a higher voltage, because that is what the resistors do, they drop the voltage down to 9V.I know a lot of people do it, but I never have, those ND coils are a good bit of kit, and on the Suzuki GS1000, which uses the twin type coil (2 of) the voltage is also 9V at the coils, possibly the same applies to the Suzuki GT380 which uses the single type coil (3 of) but I have never checked.

Coil life could be compromised if you remove the resistors, since I (normally) do a high mileage, I have left them in, maybe on lesser used bikes the problem would take longer to emanate.

It was common, before fuel injection, and still gets used today (sometimes) for cars to have the coils switched at 9V via a ballast resistor, for starting a 12V circuit was made available by an extra output from the starter solenoid, that only gave the 12v when the starter was turning, but returned to 9V as soon as the starter stopped revolving, and the engine had fired.

Massimo was the master of saving money, but not if performance was lost, that is why there are seven versions of the SOHC 750 twin frame, small differences in the welding process, less tube cuts, or bending,equals cheaper fabrication, true enough the carbs and tank changed things as well, but progress and economy can go hand in hand.I dont think tte resistors would be installed if the money could have been saved.

Laverda Corse still seem to favour the BTZ system for racing, I wonder if they delete the resistors, does anyone know?
CLEM
 
redax5 said:
Ed,
Forget the ballast resistors, not needed, wire direct to your coils.

Do you know what is wrong with your IIS.?
I have a few IIS systems at home I'm holding for spares including a Series 2 x 180.
Is it the trigger plate or the control box.?
Does the system power up for example.?
Will it enter test mode successfully.?

One other thing you need to check as well.
See how strong your magnet is in the rotor, try and see if it will pick up a small screwdriver for example.
Magnets get affected by the heat and lose their strength which stops the ignition system from working.

HTH
Red
Click to expand...

The main symptom was that in any curve setting the motor would "hit the wall" at around 5500 indicated on the tach. It would start missing and refuse to rev farther, much like a rev limiter kicking in. Steve Battisson told me about the heat related magnet problems so I first replaced the magnet in my rotor with a new neodymium magnet. Strong sucker, not the problem but the bike still hits the wall at 5500, idles great and runs fine up to that point, all curves no change.
Test mode does work, all plugs fire, stepping through their rpm ranges as they should.
The green light on the box never lights when the motor is running no matter the rpm but is lit when the ignition is on with a dead motor.
The TDC light on the plate stopped working at one point at the end but the bike still ran as before.
Timing light shows no advance at all up until that 5500rpm point where the advance starts jumping around like crazy, scattering. No degree wheel set up though so I don't know the numbers. If I set the static timing as far advanced as the plate will allow the bike runs better up to that 5500rpm point but still shuts down as before. It does at full static advance hesitate a slight bit coming off idle as I'd expect.

So, the advance function seems to be dead and either the advance is just going nuts or the rev limiter is kicking in at 5500rpm.

I'm running green Dyna coils on this bike and they've never had ballast resisters on them so I'll just continue the same. Hopefully the bike will be running later today.

Ed
 
Hi Ed,
Going on those symptoms sounds as though the control box has shat itself.
I have a couple of boxes spare at home, can do a deal if you wish.
Or just swap to a magnetic hall effect Sachse, have one of them at home as well which is a brand new Series 2 full system.
Your choice.

Good luck
Red
 
Life is good!  8)

A special thanks out to Nick for the wiring help. Finally got it all hooked up and the bike fired off with no drama at all. It revs freely on the stand, now to get the bodywork back on and go for a test ride!!
 
Great to hear it is all go!  I keep meaning to get mine out for the season but it is now tied to the rafters 'cos we're still shaking.  Bit of a fag to untie it.  Might do it for Christmas.  It now costs about $50 a month just to have it tested and registered, so riding seasons will be getting shorter ...
 
You must log in or register to reply here.
Back
Top