Stock Bosch BTZ igntion rotor and wire repair question

Paul LeClair

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Staff member
Hi all

On my desk at the moment I have the complete Bosch BTZ ignition that I removed from my RGS (120 degree crank), as well as the complete Bosch BTZ ignition I removed from my 82 1200 TS Mirage Series 2 (180 degree crank). Two questions.

1.  Comparing the two ignition rotors side by side, looking at the rotor from its "front" end (the end you see when it is installed), the keyway on one rotor is at about 3 o'clock, the keyway on the other rotor is at about 2 o'clock. I forget which came off which bike.......  ??? ??? :-[ :-[

Which rotor is for the 120, and which rotor is for the 180?

2.    As can be seen from the photo, the cloth wiring cover from the pickup plate to the Bosch boxes was cut on my 82 1200 TS, and further, all four wires have the actual insulation on each wire missing for about  half an inch or more. This is how the wiring was when I took it off the bike, it almost looks like someone in the past might have done this deliberately? Anyway, the wires themselves are intact, what would be the optimum way of repairing this? My first reaction was to just cut all four wires and put proper splices in with shrink wrap on each repair, but now I am wondering if it would be wise to cut and splice the wires or just cover each bare section?

Paul LeClair
 

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redax5 said:
180 rotor does not have the spanner provision on it

Hi Red

in this particular case, both rotors have provision for a wrench to be used on them to turn the crankshaft.

also of interest (to me anyway) I just noticed that the lobe on the rotor Steve just identified as for a 180 is much wider than the lobe on the rotor for the 120.

Thanks to you both! Amazing all the little differences between the various motors and various years.

Now, as to the bare wires, do I cut and splice, or leave them intact and just cover each of them up somehow?

Paul LeClair
 

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my mistake, missed the Series 2 x 180 bit
Series 1 rotors have no spanner provision

 
redax5 said:
my mistake, missed the Series 2 x 180 bit
Series 1 rotors have no spanner provision

I will have to go look, I also have a full Bosch BTZ system kicking around in a storage box that I took off my 79 1200 years ago, so three Bosch BTZ systems, from 79, 82, and 84, and each uses a different rotor, bloody hell....... The more I learn, the more I realize the less I actually know........ ;) ;)

Paul LeClair
 
Hi Paul, when I replaced the pick up wires on my RGS, I found the insulation had broken down in at least two places, one near the connector end at the CDI units.

I'd recommend changing the entire length. I was lucky enough to have a couple of lengths of sheathed cable of the same thickness.

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Hi Chappo

I am just getting the various Bosch BTZ systems ready for long term storage against the time when a completely stock Laverda triple will be worth millions and I want to return the various bikes to stock configuration....... :o 8)

you know, looking at the actual construction of the stock very heavy duty pickup plate and the construction and mounting of the pickups, the stock system is pretty darn robust and well made, especially for when it was constructed. Way ahead of its time, especially if set up by someone who understood the importance of "timing" the stock pickups in relation to each other so the ignition timing of all cylinders advanced at pretty much the same time to minimize the engine lurching as the advance changed.

all any of the three BTZ systems I have taken off my three triples probably really need is to do what you did and replace the now 35 + year old wires that have lived in a fairly tough environment all those years and they would be good for another 35 + years more than likely.

I have to confess I am not using many of the programmable aspects of the Ignitech, all  I have done so far is put in an ignition "curve" that is not all that different from the stock Bosch system........

I am wondering if anyone has pinned the stock Bosch pickups for an Ignitech connector, I bet that could be made to work, in fact I would bet that it might be fairly simple to do....... hmmmm. Anyone?

Paul LeClair
 
Hi Paul,
A number of the electronics R&D guys I do work for use flexible teflon coated wires for aggressive environments similar to the
type sold by Daburn, might be worth a look.
http://www.daburn.com/high-temperature-wire.aspx
 
Paul,

Replace the entire length of wiring, join as close to the pick-up as you dare.  The rest of the original insulation is bound to crumble sooner ot later.  Fix your new wire to the pick-up with a blob of silicon sealant or similar to support the soldered joint a bit against vibration.  You can source nice silicon-rubber sheathed wire from your local RC model supplier, quite common for them to use it.  It is quite impervious to heat and stays supple almost indefinitely.  Available from 0.15mm? to about 1.00mm?, 0.5mm? should be more than enough to carry the pick-up current, might be a bit difficult making the connection to the box of your choice though.  0.75mm? is probably more practical.

Only thing to observe when using the original pick-ups with a different igntion control is to get the polarity the same for both pick-ups.  Can be checked when everything is hooked up and you pass a screwdriver blade over the magnetic poles.  Generally, the spark should jump when you pull the blade off the magnets, not when the blade contacts them.

piet
 
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