1200 cutting out any suggestions please

With oem HKZ, the "generator" ( its an alternator, the dash gen light lies, grin ) for on bike 12V electrics, was almost adequate, at around 7 amps output. Given the HKZ ignition had zero power demand upon the 12V system ( ignor the stop relay 20mA ). The initial IIS was designed around a modern "HKZ" equivalent or better, and it was better. The IIS long box will cold crank down to 2V supply, with full 350V available for the ignition coil primaries, provided the on bike system has at least 9V of battery, at switch on ie it was an internal self generating system. The short IIS module was only meant to be an carry with you breakdown replacement for long tours or rides. Demand on the bike 12V system from the IIS long box was an average 1 to 1.5Amps over entire rpm range. Remains some of my best work, to this day.

Perhaps it is why i have a soft spot for the oem HKZ, set a design goal for me, at a time when inductive discharge ignition systems were in full command on many bikes, save for some like the Kwaka H2 ( not sure about the widow maker however ). Dunno, if i had a Laverda with a well setup/maintained HKZ and a spare module in the kit, would still ride around with HKZ fitted Laverda. The actual quality or the wound devices is very good. MTBF would be on par with any modern full blown digital ignition product, i would think.

Lot of rooting around replacing a HKZ, with inductive discharge replacement, alternator upgrade for one......

BTW, has me a bit tricked on the ride away design comment, had to be a stop function somewhere to defeat the self generating HKZ operation, maybe am a bit slow, very possible. What was an after thought is the diode in the park lamp position of the ignition switch circuit. There was a functioning circuit to "back feed" the park voltage into the run circuit of the bikes electrical system. Glad to stand corrected on any points. j.
 
Oh just recalled ( ride away no ignition key ), mate lost his ignition keys while out, rings me, i pull up, while he is talking to me, reach under his RGS fairing, yank out the ignition key connector, alligator clip from pocket, short out two adjacent pins, harness side, press start button, bike running, he did not finish his sentence.... the ride away Laverda for free was still present in the dying days...had some fun in the day...j
 
Ha ha. I did the same with a friend's 350 Honda 4 back in the day. She'd also lost her key and wanted to be able to get the bike home.
I had a Honda 4 myself so was familiar with the wiring. Mine was a 750, but the wiring was pretty much identical. Side cover off, un-plug a couple of bullet connectors and plug one of them into the other wire - presto. Hit the starter button and it fires up. No tools or jumper wires required and took all of thirty seconds, and that includes removing and re-fitting the side cover. 1970's Hondas were such easy bikes to start without the key that I always locked the steering on mine.
 
Honda 4 750 ( Cam, series 0 sand cast was it? ), loved 'em, all i had to do was get an exhaust pipe in front of them, gone... nothing like a Kettle/Waterbottle on atrocious castrol basic mineral 'stroker oil... was like something from a Sci-fi movie.... small bike, huge smoke screen... traffic light torque monster was the Kettle, same torque as Kwaka Z1, i rode a friends Jaffa Kwaka...his Jam Jar XS1 and 2, another time.... old bloke not staying on topic. j
 
Used to have a Yamaha XJ 650 in a previous life, was wondering one day how I would get it started if I lost the key. Worked out which fuses to bridge and from then on I carried a short bit of wire, just in case. Took about twenty seconds to get the bike started.
 
Reference the ride away without the key , I think pretty much all production triples would have had the engine stop relay fitted , so would need the key . Probably the ride away story came about through journalists sampling very early examples without the relay fitted , the discovery being made then .
The thing is the CDI system works pretty much as a stand alone system , all you have to do is get the generator/alternator rotor turning and you have sparks .
I remember reading somewhere this Bosch CDI system was originally intended to be fitted to a lawnmower before Laverda chose it to power the triple .

Remove this stop relay and the engine will start via the battery powered starter motor , I`m just trying to remember about the stopping side of things...On the Mirage I removed the stop relay ( for reasons connected (sorry) to that horrible plastic multi-connector under the rear of the tank ).

Obviously the right hand emergency handlebar switch ceased to work , but not sure if the key would stop it , pretty sure I didn`t stall it to stop it , perhaps I turned the idle down to nothing ( which is what I think I actually did ) . Maybe there is some connection from the key through the fuse and battery to the CDI , though can`t really see where .

Maybe someone with a 180 degree CDI triple will remove the stop relay and let us know if the motor keeps running when you switch off the key ( which in theory it should ) .
After wearing out two CDI ignition units I eventually fitted a WItt/DMC system which worked very well ( and I got the emergency stop handlebar switch back again too ) .

Had a Triumph Blazer 250 Street Scrambler single which came as standard with a Lucas 2MC capacitor (about 2"x1") fitted which enabled you to start and run the bike without the battery , although lights , indicators and horn etc. would only work when the revs were high enough .
 
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The plus side of this is that the HKZ bikes will always fire up with a push start and keep running with a flat battery if you aren't using lights. This is the best feature for me considering the alternator was so pathetic.
 
I have to say after having similar fault finding problems with my 77' jota CDI ignition system, the bike was off road more than on, i finally bit the bullet and arranged a slot with Keith Nairn in Glasgow - he fully sorted it with an Ignitech ignition system and uprated alternator, also sorting my valves/guides and head out for me at the same time, very high quality standard of work and you wont look back...as has already been mentioned ,these systems were OK 45 years ago but most will by now be past their best.
 
iis_iis said:
Oh just recalled ( ride away no ignition key ), mate lost his ignition keys while out, rings me, i pull up, while he is talking to me, reach under his RGS fairing, yank out the ignition key connector, alligator clip from pocket, short out two adjacent pins, harness side, press start button, bike running, he did not finish his sentence.... the ride away Laverda for free was still present in the dying days...had some fun in the day...j
Click to expand...
That is it how it works, just pull the connector fron the ignition switch cable and connect the right wires, I think red and orange.
 
andre g said:
That is it how it works, just pull the connector fron the ignition switch cable and connect the right wires, I think red and orange.
Click to expand...
That is simple hotwiring. I did it whilst touring on my SF2 last summer when the wires to the ignition switch came off. Brown and red if I remember.
To bypass the ignition switch, no need to pull the wires off, just pass a pin through the 2 wires.
Paul
 
Andy, no typo, IIS long box used a dc to ac to dc convertor section, added a self sustaining winding on the magnetic transformer, to the multiple windings required to make a full functioning CDI. There was a 12V winding to support the convertor primary winding control circuit, plus an isolated winding to support the opto couplers for ignition coil driver transistors bias. Indeed i suppose you could call the sustain winding a type of homage to the HKZ exciter coil. Seen iis long modules fully function to 1.8Vdc input ( well sagged 12V battery ). Given the series compound starter motor still works to a low of 6V cold cranking, inductive discharge systems stop around 9V input due to under saturation of the primary winding.

The type of convertor i used in the iis long box would drive into a dead short circuit on the coil drive outputs, no effect whatsoever, no distress and no additional power demand. There was no restriction on any connected coil(s), 3V 4V 6V coils, 12V coils, primary resistance types, 0,7Ohm coils to 3 Ohm coils, even the dreadful Bosch GT40 coils could be driven safely ( do not recommend this be done as a choice ). The key feature was the 350Vdc impressed across the internal crucial component capacitor, was available for connection to any coil at anytime, even parallel primaries ( again bad practice ). Only took 2 weeks to design and construct the first module of that hardware, years followed in sorting out the digital firmware...long years. HTH j
 
Paul Marx said:
That is simple hotwiring. I did it whilst touring on my SF2 last summer when the wires to the ignition switch came off. Brown and red if I remember.
To bypass the ignition switch, no need to pull the wires off, just pass a pin through the 2 wires.
Paul
Click to expand...
Yes that works, also. Though hard to get a bent wire into place reliably at times. Personally i use a clothes peg as it provides good insulation for the dangling wires on my 79 Jota, it does not even have an ignition switch.... acts like an over rev limiter, when the vibration builds the peg falls off and cuts the motor....true... times are hard....grin.
 
Thanks gents for all your replies, I spent Tuesday afternoon cleaning and remaking the alternator and ignition connections, ran beautifully so I took it out, lasted about 1/2 mile then cut out, pushed it back home, still wouldn't run
The volts from everywhere looked correct, and rechecked the earth's etc

that only left the silver ignition box...
I've now booked it in with Keith Nairn for a new system. As has been pointed out, 45 years is a good run for electronics, its a nice bike to ride, so at least I may feel more like using it.
 

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Yes I was there 2 hours waiting for recovery, luckily I have cover with carole nash /AXA with my insurance, so no charge.
The guy who picked me up said their company worked for all the major roadside assistance companies
 
Nice Motorcycle Steve, looks new, grin. Shotgunning the electrical issue(s) is one way of ridding a problematic intermittent fault. Locating the actual problem has a useful outcome in regards to confidence, all the same. Can happen the removal of old parts does not remove the original fault or issues. Does narrow down the likely source of a fault, the new equipment, can then concentrate on what remains on the bike relevant electrical parts. Redax does some very nice work, love their machining skills and outcomes. j.
 
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