End of Tether

[mgelder]

old morini's are not the easiest bikes to start.

They are when they've had their rotor's remagnetised and their coils rewound, though.

Taking a bike with a tired rotor and crumbling coils and then finding it's easier to start after a different ignition system has been fitted doesn't prove that the original system is fundamentally poor.

Taking a bike with a tired rotor and crumbling coils and then finding it's easier to start after a rewound and remagnetised standard system has been fitted does, however, prove that the original system is fundamentally good.

So what needs to be done is to compare the cost, availability, convenience, etc, of an aftermarket system with the cost and availability, etc, of a refreshed standard system.

Unless, of course, you really *need* to start your bike by hand in sub-zero temperatures.

It's below zero as I type this, and the only thing I'll be starting by hand today is the coffee machine.

[huub]

It's below zero as I type this, and the only thing I'll be starting by hand today is the coffee machine.

Took the falcone to work today, a 80 km round trip , i think it was minus 7 c when i left home.
it started first kick.....
i tend to ride bikes all year round, all my morini's have been used as daily transport at some time.
bikes are fun , even in the cold.
Push starting a bike in the snow is not fun.

my first morini was 2 years old when i got it,
unless it had crumbling coils and a demagnetised rotor by then i think can judge how a morini is supposed to start.
if it turns out it had crumbling coils after two years you've just given me another reason to call it poorly designed.

[buell1203]

Totally agree with hub. Ride all year and you find out how reliable your bike is and it can remain fun.

There is no way 30 year old ignition systems can be as good or as accurate as modern digital units. I do however have a soft spot for battery and coil ignition. It may have its faults but seldom totally fails.

I investigated converting my bike to this system but it is not easy to achieve the right dwell.

[MarkB]

I'm with Martin on this one. My '75 Strada and '76 Sport are both good reliable starters, cold or hot, good weather or not. The Strada was rewound about 6 years ago, and I expect the same has been done to the Sport at some time.

Getting carburettors properly synched helped the eagerness of both engines.

Regards, Mark.

[buell1203]

Yes the standard system can be good but work out the costs of the rewind and re magnetisation,then maybe a new pickup or two and you have spent the same as a modern digital system. Obviously not the excellent sachse system but hpi is circa £220 and programable.

[Alfonso70]

I've had a boyer system on my bike for years with no problems (unless you count easy, reliable starting, good low idle speed etc as a problem) i am interested though in the new 300w alternator one of the ignition people are now offering, the only thing i cannot see is as the new flywheel is not positioned by the keyway how would i be able to check/set the timing!

Re: a previous comment about melted piston because of the wasted spark system on a boyer, I thought the the newer ignition systems on New Yorks, Darts etc ran off the crankshaft and were therefore wasted spark. How did the factory get round the problem of melted pistons?

tony

[EVguru]

the only thing i cannot see is as the new flywheel is not positioned by the keyway how would i be able to check/set the timing!

With some difficulty.

Re: a previous comment about melted piston because of the wasted spark system on a boyer, I thought the the newer ignition systems on New Yorks, Darts etc ran off the crankshaft and were therefore wasted spark. How did the factory get round the problem of melted pistons?

tony

The Boyer only has one coil output, so both cylinders fire at the same time. There are now four sparks for each cylinder, THREE of them wasted. Not a problem on narrow Vees lika a Harley, or a wide Vee like a Ducati, but can be a problem on a midling angle Vee like the Morini. Even than it's only a problem with a weak mixture.

Morinis never suffer from fuel starvation at high speed, dirt in the fuel, or split their 30+ year old inlet manifolds do they?

[tankstraddler]

Here is the latest. I decided to re-make the earth connections at the head-stock, not that they looked poor but just thought that a clean up could only be beneficial. I checked the accessible (unsheathed) sections of the green wires to the transducers and they looked OK but the wiring of the transducers confused me slightly. When I bought it the machine was fitted with red pick-up and black transducers, now NLM pick up and black transducers. The schematic diagram in the blue book suggests that the transducers are linked by a white wire (mine are) but the detailed diagram does not seem to show this linking.

On the subject of blue book wiring diagrams, do they correctly show the position of the various connectors on the fuse board? My connectors do not completely correspond.

Although the wiring has clearly been changed in part over the years, it does seem to have been done by someone who knew what they were doing. The machine is 1975 so may have had red transducers originally but reading here suggests that the black ones will work with more or less any pick up. That said and as observed by SupermotoDave, I tend to favour original equipment so can anyone repair pick ups and check that they match the transducers and does anyone know where I can get an original rectifier to replace the Boyers Bransden unit (agreed that that is unlikely to be relevant to the position here though.)

The machine has never run right during my ownership, or only briefly, so it could be that it has been wrongly set up for years and been palmed off by one dissatisfied owner to another. I say this as it is easier to diagnose problems on a machine which was once running correctly on the basis that the parts fitted were once compatible and functioned correctly.

Having bought the special tools I removed the rotor today. I held it upside down and was able to suspend a 2lb impact screwdriver from each magnet which makes me think that the magnetism is pretty good. I also re-measured the resistance in the windings from the green cable but using the newly cleaned frame earth rather than the engine as an earth and it came in at an unbelievable 304, checked several times.

I am thinking bad connection somewhere or something failing under operating conditions.

[72degrees]

Is there a dedicated earth connection from the engine to frame or are you just relying on the engine mountings? I have a cable running from the crankcase screw that is just behind the lug for the clutch cable to a common earth point on the frame for the ignition and charging system. That's with a 350 in a 250 frame though so the transducers are mounted under the seat and the earth point is one of the mountings for the reg/rec unit (original but now12v item).

No white wire linking the transducers on mine when I was still running the original black units. Certainly not now I have the NLM replacement ignition box and coil setup. This has been performing very well with an OEM red pickup.

[EVguru]

The white wire is an additional earth. Later alternator stators had a white wire as an earth direct from the high voltage coil.

If the potted in earth lead has corroded on an ignition box, you can replace it with one from the earth terminal in the connector.

The pickup earth is important too and you could also run an earth from the pickup direct to the ignition boxes.

When in doubt it's always worth connecting the alternator high voltage (green wire) direct to the ignition boxes with nothing else in the circuit. At the least, disconnect the ignition and any kill switch.

[tankstraddler]

The white wire is an additional earth. Later alternator stators had a white wire as an earth direct from the high voltage coil.

If the potted in earth lead has corroded on an ignition box, you can replace it with one from the earth terminal in the connector.

The pickup earth is important too and you could also run an earth from the pickup direct to the ignition boxes.

When in doubt it's always worth connecting the alternator high voltage (green wire) direct to the ignition boxes with nothing else in the circuit. At the least, disconnect the ignition and any kill switch.

Thanks, Paul. I can see that if I run the green cable direct from the alternator to one transducer and piggy back from there to the other I will eliminate possible problem areas like the switch, poor connections and failed existing wiring at the expense of not being able to stop the engine on the key so I will give it a try.

You say that the white wire linking the transducers is an earth, presumably a back up so that if the potted in (blue) earth wire fails in one it will be able to earth through the other so is your suggestion that I replace the white linking wire with one wire from each transducer connecting it to its own new machine earth so that each has two wired machine earths?

I am not sure about the pick up though: where would I connect an earth wire to it please and where would I connect it in the transducer? Should I connect it to the contact in the transducer with the white cable so that it will earth through the new machine earth to be taken from that contact? Thanks for your help so far.

[EVguru]

You say that the white wire linking the transducers is an earth, presumably a back up so that if the potted in (blue) earth wire fails in one it will be able to earth through the other so is your suggestion that I replace the white linking wire with one wire from each transducer connecting it to its own new machine earth so that each has two wired machine earths?

I don't ever recall seeing a white wire linking the ignition boxes, my 1977 Sport doesn't have one. The K series and later bikes had the boxes connected to the stator plate with a white wire.

(Picture from the Dutch club site)

I'd just do a continuity test between the white terminal and frame to check the blue wire is OK. Checking between frame and engine is a good idea too (the white wire was a backup for that).

Most of the voltage that is present on the high voltage capacitor in each ignition box is present on its tachometer terminal. This is the one marked ''C. GIRI'. Use a digital meter to measure the voltage. it should be in the tens of volts range whilst kicking. Disconnect the pickup input to make sure it's not firing and discharging the capacitor, you could have a faulty coil/lead/plug. I've heard of a faulty tach causing problems, but the spark would have to be bery marginal in the first place.

I am not sure about the pick up though: where would I connect an earth wire to it please and where would I connect it in the transducer? Should I connect it to the contact in the transducer with the white cable so that it will earth through the new machine earth to be taken from that contact? Thanks for your help so far.

The pickup is a three terminal device.

(Picture from the Dutch club site)

There are two tigger leads leading to the ignition boxes, plus a short earth. Make sure this earth connection is good. It wouldn't hurt to run a wire up to the ignition boxes (white terminal).

[Ming]

"Most of the voltage that is present on the high voltage capacitor in each ignition box is present on its tachometer terminal. This is the one marked ''C. GIRI'. Use a digital meter to measure the voltage. it should be in the tens of volts range whilst kicking. Disconnect the pickup input to make sure it's not firing and discharging the capacitor, you could have a faulty coil/lead/plug. I've heard of a faulty tach causing problems, but the spark would have to be bery marginal in the first place."

So has anyone measured typical voltages (eg, kich, tickover, higher revs) at the input to the CDI unit? I've looked through lots of forum posts, but not found anything other than the above.
I guess if the voltage at the rev counter terminal is in the order of tens of volts at kickover, the top of the voltage divider must be roughly 8 times that (33k and 220k ohm).
It would be handy to have for troubleshooting.

[Sonomamorini]

Can anyone recommend what plug caps e.g. NGK and reference number to use ? THX ALEX

[Ralph]

There's a post on here somewhere it's recent and shows how to remove the resistor from the plug caps
worked well on mine.
If you do go this route get the ones with the slight angle at the top as they have the screw
holding the resistor, the straight ones can be done but it's held by a washer and has to be pulled out.


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