Replacement of the Morini timing belt should not be a real problem. The belt is commonly used in industry. Print on an original Pirelli belt from left to right (see photo's below):
Moto Morini;
styled "P" of "Pirelli", sometimes Isoran/Pirelli is printed;
made in Italy;
124L075. This is the size. 124 means length: 12,4 inch, 075 stands for width 0,75 inch and
L means you'll find teeth on the inside only. If it would say "XL", then you would have a
belt with teeth on both inside and outside;
A, refers to the (sub)size. You can find three types: A, B or C belts, from Pirelli that is.
These letters refer to the production tolerance. The metal toothed cam in the engine, on which the belt
is placed has got an A, B or C stamped at the factory. By means of measurement a match was made in the
factory between top and bottom cam and the tolerance was set. The A, B or C belt versions each differ
0,3 mm in length.
F8, production month and -year in the 80s, 90s. "F" stands for June and "8" means 1988.
Remarks:
The series of belts E2 up to D4
(May '82 until April '84) were called back by the factory at the time,
due to a faulty production, but this factory notice did not reach outside
Italy.
Difference between the original Pirelli,
made for Morini and other makes, all made to DIN (German Industry Norm)
is that the teeth of the Pirelli belts are 0,1 mm higher.
Fitting of a non-original belt made by Gates or Continental, or others can cause
problems: too tight or too loose. A friend of mine had a too tight belt, which
produced smoke & stink, after fitting. Someone else could take a non-original
belt off both cams by just holding it between two fingers.
Please note:
Some people have reported hearing louder bearing noise
(probably from the right-side cam bearing) after installing a new cam
belt, even if the belt tension is within specifications. Sometimes, fitting a
belt which is not too tight will eliminate the noise.
How long will the belt last? That's important of course. You should replace the belt from time to time,
to prevent trouble. The original Pirellis should last between 12,000 and
15,000 km's, or after a maximum of 36 months of use. If you would not use your
bike at all, you would still have to replace the belt, because the material gets
older and dries out. A German technician once found out that the forces, which
work on these belts are twice as much as what they are designed for, accoring to
the German Industry Norm (DIN). So it makes sense to replace this part from time
to time. My own bike has an "A" in both metal cams. I have replaced the original
Pirelli belt successfully by a Mitsuboshi one. From time to time I have checked
the Mitsuboshi replacement belt and it seems to be right.
See the Mitsuboshi site on their products and applications.
Different makes Pirelli still produces the original Morini replacement belts, but also other factories
like Continental, Gates and Mitsuboshi produce them. These "nylon"/rubber belts, which might
even have kevlar added, are also used for other industrial machines and not just in Morini
engines. So next time, at the baker's, have a look inside the machine that slices up the
bread. You never know, you could find a "124L075" belt ;-))
The Morini manual mentions a slack of 6 mm for the timing belt. That is too much.
The belt should have a tighter fit.
Click for larger size. The original Pirelli belt with "Moto Morini" print.
On the right "F8" is printed (month of production) and an "A" (sub-size) can be seen vaguely on the left.
Cornelius Smallenburg, secretary of the Dutch Morini Club gave me an example of a Gates belt, which he could, after 2,000
km's, take off with his fingers. This is no judgement on the Gates quality, but it does mean you have to be carefull with
the right fitting. Just imagine what would happen inside the engine if something went wrong, while changing gears. Don't
forget, the bottom cam only makes contact with the belt on 4 to 5 teeth. Cornelius Smallenburg recently experienced (with a
Mitsuboshi belt), that after 16,000 km's the fitting of it was still better, than the new one he was going to fit (too loose).
This had to do with the tolerance of the production. On Mitsuboshi belts, you won't find the A, B or C type belts as from
Pirelli. So if a Mitsuboshi does not fit well, too tight or too loose, try another one from a different lot. Easier said than
done of course, because once you have bought one, I don't think a your supplier would take it back. Most makes/brands should
be petrol and oil proof, but it is worth to check this. My own local Morini dealer sells a lot more Mitsuboshi belts, which
makes them more "fresh'' and which will mean they will last longer. On the other hand, if a Mitsuboshi won't make a
good fit, invest in an original Pirelli, they are still available but they are a lot more expensive!
The Morini ignition: a pain in the ****?
Not necessary, if you read this article carefully :-)
Definitions:
TRANSDUCER - black or grey box under the fuel-tank. It consists of electronic components
and a coil all in the same housing. Warning: NEVER connect the battery to
the transducers, because this will blow them up;
COIL - used in conventional ignitions in combination with a set of contacts.
In the transducers used by Morini, a coil is integrated. The coil works identical as a
transformer. A low voltage in the primary windings is transformed into a high voltage in
the secundary windings by induction. This high voltage creates a spark between the electrodes
of the sparkplug;
PICK-UP - two (V-twin), or one (singles) coil(s) in a round red
or black plastic housing, situated on the left-hand-side of the engine,
between both cylinders. In the middle a small magnet, which is fixed to
the cam-shaft, rotates and gives a signal to the transducers when to discharge
their built-up charge to the spark-plugs;
clockwise: red pickup, pickup magnet, flywheel, alternator. (Transducers are missing on this
picture).
ALTERNATOR - both V-twin and single models have an alternator (produces
alternating current). Both yellow wires from the alternator are connected to to
the rectifier/regulator. In this article we will not mention the regulator. Furthermore
a red and green cable come from the alternator. Some later models also have a white wire.
White is an earthwire (on earlier models the alternator has no seperate wire for earth).
The green wire is important for the ignition, as it is connected to a seperate (yellow)
coil inside the alternator, which "feeds" the transducers.
2 yellow wires: to rectifier;
1 green wire: from seperate yellow coil to fusebox and ignition switch;
1 red wire: to pick-up. (See below in this article).
Note: the off-road models like Kanguro & Camel have a mixed 6V/12V
system. 12V directly to the headlight, 6V to a small battery for the rest of the
electrical system. The 125cc & (250cc ?) bikes have an electrical system of 6V.
Warning: NEVER connect 6V or 12V directly to the transducers.
It will destroy them permanently.
The alternator & flywheel. Click on photo's for larger size.
The back of the alternator with the name of the producer "Ducati Elettrotecnica".
Another picture of the alternator/generator
with it's 4 wires: 2 yellow, 1 red, 1 green. Between the metal mass of the generator
and green wire you should measure something
between 170 and 250 Ohm. In that case the
yellow ignition coil is OK.
(On several coils I measured 220 Ohm).
Photo of the alternator still on the bike. The yellow coil is connected to the green wire.
General In general, in the Netherlands, Morini V-twins have not got a good name, both with the public as in bike-shops. They are
supposed to be bikes, which always suffer some kind of trouble. Earlier this year, I heard three stories in a row about
various bike-shops where they had a Morini somewhere in a corner, which was "given up". Various attempts to get the engine
back alive had failed and the bikes were left with the hope one day a buyer would turn up. Also some members of the Dutch
Morini Club are not too happy with their V-twin.
Strange, when you think about the fact that the 3½ in both Italy and England is known as a very reliable machine, which is
nearly "bullet-proof". In the Netherlands, many problems were caused by lack of knowledge and many bikes were never serviced
properly, because they were cheap. It is remarkable that 50% or more of problems with the Morini V-twins are caused by the
ignition. In the Netherlands there is little knowledge on the Morini ignition (made by "Ducati Elettrotecnica"). Even our
own newsletter Rebello has published little on this subject in the past.
Most that was written is already some time ago. So a good reason to publish this story. In the past I have learnt a lot on
the ignition, information I can share with you.
In case your ignition causes problems, first of all measure the electric resistance of the seperate coil in the
alternator, by taking off the green wire from the fuse box. Connect the green wire to an Ohm meter and connect the other
terminal of the Ohm meter to earth ( - ). You should measure something between 170 and 250 Ohm. On a number of alternators,
I have measured 220 Ohm for the ignition coil, so this is probably a normal value. In case the value is less than 170 Ohm,
the windings (or insulation) of the seperate coil for the ignition are/is broken and the coil should be re-wound, or the
alternator should be replaced.
Different versions of ignition parts First of all, I would like to give a description of the various versions of the
electronic ignition, as we know it from the V-twin models. Also I will mention the
ignition of the singles, like the 125 single ("half" of the 250 V-twin and 250 single
"half" of the 500 V-twin). There are big differences between the parts for the singles
and the V-twins and these differences can lead to big problems, in case you "mix" the
wrong parts.
The ignition as fitted by the factory (OEM), was built by Ducati Elettrotecnica. The quality of the
electronic ignition is good, but perhaps a little "under-sized". Some of the components could have been
a little more "over-sized" to last longer and also to give a stronger spark. Although the construction of
the transducers is simple, the technical theory is far from simple. A German technician by the name of Franz
Grabowski has published an article on the ignition pick-up. Elswhere on this page you can download this
excellent article (in Adobe .PDF format), but unfortunately it is in German and too complicated to translate
into English. You can take it from me that the pick-up is a simple, but well designed part of the ignition.
I don't think it is necessary to change the Ducati Elettrotecnica ignition of your Morini for an ignition of
another make. As the Morini V-twin models are getting older, more problems can be expected. Another problem is
that original replacement-transducers are no longer made.
On the left: transducer of the first generation. The red dot sticker indicates that it is of a Morini 500. On the
right a transducer of the third generation (with bulge). The second generation has the same shape as the first generation
but is grey of colour instead of black.
Fortunately in the past few years professionally made
replacement parts (f.i. a better than original pick-up) were introduced, mostly in Germany. Even a digital system
is worth mentioning. See on this page under alternative systems. Basically you can stick to the original ignition.
Even if original replacement parts are no longer made, parts are still reasonable in price, compared to many modern
bikes. The original ignition also has the excellent feature to retard the ignition (and to prevent backfire when
using the kickstarter), when the engine is started and also to advance the spark timing above 6,000 rpm.
Different versions of transducers and pick-ups Over the years Moto Morini used the Ducati Elettrotecnica system (all-in-all 3 different versions of transducers
and 3 different pick-up's). Later, on the bikes built under Cagiva management (>1986/7), the Japanese
Kokusan ignition, was introduced.
Bikes involved are: Excalibur, Dart, New York, Camel X3 and Coguaro (perhaps also Kanguro X3?). This ignition was
integrated in the alternator, which also housed the pick-up. So this last item was no longer fixed to the end of the
camshaft, as on previous models. This means that the cam-shafts of Excalibur, New York and Dart are probably
shorter and also that the end of the cranck shaft probably has a different shape. So on these models you can't
fix a Ducati ignition. On the earlier Morini's like the 3½ and 500 you can't fix a Kokusan ignition. So keep this
in mind, in case you buy used parts from a breaker.
The very different Kokusan alternator. It was used for the later V-twins, like Dart 350/400, Camel X3, Excalibur, New York and Coguaro. The black coils, on the photo above the alternator windings, are for the ignition.
A close-up of a 1st generation black transducer, made by Ducati Elettrotecnica. Vaguely you can see the
number stamped in the plastic housing: 323921, which identifies it as a transducer for the 3½. The green dot is missing.
A close-up of a 1st generation black transducer, made by Ducati Elettrotecnica. The red dot identifies it a a transducer for the Morini 500. See the number stamped in the plastic housing: 323934.
3rd generation grey transducer, with bulge. Note the sticker which states to use it only in combination with a black pick-up. This particular transducer is made in Italy by Zanussi (!)
Three series Ducati Elettrotecnica transducers The ignitions of the 3½, 500, 250 V-twins and also the 125 and 250 single consist
of three different series of transducers and also three different pick-up's (2 different
red ones and 1 black one).
Each model bike (125 single, 250 single, 250 V-twin, 350 V-twin and 500 V-twin) have
their own specific transducer(s), which differ from each other, because they have to create
a different advance of ignition. The 3½ models have a maximum advance of 34o and
the 500 models have an advance of 30o.
The transducers of the first and second/third generation also differ,
because the first generation can only work properly with a red pick-up; the second/third
generation can only work with a black pick-up! The black pick-up has not got a set of
diodes, which are fixed inside the red pick-up. In the second and third series of transducers this
diode is fixed inside the transducer itself.
When you realise there were at least five different engines, each with three generations
transducers and different pick-up's the number of possible combinations is huge! The bad part
is all these different components can be combined and you will get the engine started on it,
but with the wrong combination transducer/pick-up, or two different transducers you will get
an engine of which the ignition will not advance, but will delay at certain revolutions
per minute. Another possibility is an engine in which the timing of only one cylinder is right.
With the wrong combination of ignition parts, the best scenario is the engine will produce more
vibration, in the worst scenario, the engine will break down (piston will seize, or a hole in
the piston).
SO IT IS IMPORTANT TO HAVE THE RIGHT COMBINATION IGNITION PARTS ON
YOUR BIKE AND TO CHECK THESE, BEFORE YOU START LOOKING IN CASE OF BREAK-DOWNS.
The black pick-up for the second and third generation transducers. Mostly the sticker is gone.
The matching magnet for the back pick-up, identical to magnet for the 2nd red pick-up.
Three different sorts of transducers & three different red or black pick-up's (see also the table below):
First series transducers, box-shaped black, connect a red pick-up.
Second series of transducers, box-shaped grey, connect a black pick-up
(see photo above on the left).
Third series of transducers, grey with a bulge (a heavier
coil was built inside), connect black pick-up.
Two sorts of red pick-up's and a black one. Both types of red pick-up's & their matching magnets should be kept together
as a set, as the magnets cannot be swapped. Both types of red pick-up's work identically, but the angle between the metal spots,
which you can see through the potting, is different, and both magnets are different as well.
The first (older) red pick-up.:
The older version has a magnet with a grey colour and it looks like it has been milled.
Also the name "Ducati-Elettrotecnica" has been written on it in very small letters. The matching
pick-up can be recognised by the soft metal parts of the coils inside. The soft-metal strips inside
have a width of ±13 mm.
The second red pick-up.:
(used until ±1981) has a copper/golden colour magnet, which looks like it is made from a pressed piece
of metal. It has no writing on it. The soft-metal strips inside are ±7 mm wide. In case you would swap
the magnets of these red pick-ups, you will interfere the ignition timing badly. Both these red pick-ups
should be used with the black transducers (square boxes) only.
The third and last type of pick-up's used by Morini is BLACK.:
The black pick-up originally has a sticker on it to only use it in
combination with grey transducers (2nd or 3rd generation) only. The magnet
of the black pick-up is identical to the magnet of the 2nd type red pick-up.
On the left of this photo the first red pick-up, on the right the second red pick-up. Look at the
difference of the internal coils and the different magnets.
Backview of both second red pick-up and matching magnet. The magnet is identical to the one of the
black pick-up.
Note: the diagonal black line is a shade from the sunlight.
Cracked potting on a broken red pick-up.
Tip 1: a common problem of the Morini ignition is to get it in phase. When the timing of the front cylinder is set
correctly, the rear cylinder can be slightly off-time. When you set the timing, based on the rear cylinder, the front
cylinder can be off-time slightly. This has to do with the position (towards each other) of the two sets
(see below in the In-Depth German article) of horseshoe shaped metal plates inside the pickup.
Pietro Ligorio has thought of a simple, but efficient method to correct this. (Another way to
correct the spot-on timing of both cylinders, is to use an aftermarket pickup, made by Marcus Heilig
(see below)).
Tip 2: Pietro Ligorio also drew a small electronic circuit to connect
an electronic rev. counter to a 3rd generation (grey) transducer. Normally this is impossible, as the grey transducers
do not have a connection for an electronic rev. counter. Bikes with these types of transducers were fitted with a mechanical
rev. counter. I have seen this small circuit integrated in a cable and hidden under the fueltank.
Tip 3: as I noticed myself a Morini 500 will start and run on the transducers and matching pick-up of a 3½.
The difference in advance can easily be compensated by re-setting the ignition with a stroboscope. (The maximum advance
will be 30o again). A 3½ with transducers and matching pick-up of a 500 is also possible. However, you
cannot/should not use two different transducers on one engine or a wrong transducer/pick-up/magnet combination.
The numbers on the various transducers are as follows:
Transducers
1stseries
black, square
2ndseries
grey, square
3rdseries
grey, bulged
"Aftermarket"
red, bulged
350
number 323921 (green sticker)
number 323971 (green sticker)
number 323982 (green sticker)
number 323987 (see text below on availability)
pick-up
red
black
black
black
500
number 323934 (red sticker)
number 323974 (red sticker)
number 323984 (red sticker)
pick-up
red
black
black
125B
number 323923 (blue sticker)
pick-up
red
250T (single)
number 323931 (?? sticker)
pick-up
red
250V (twin)
number 323921 (?? sticker)
pick-up
red
250 2C (1981)
number 323921 (green sticker)
pick-up
??
As you see, we don't know all the numbers of the smaller models. If you can tell us more, please e-mail
the webmaster.
TRANSDUCERS, self-build, repair, replacement Inside the transducers of the Morini ignition there is a small electronic
circuit and a coil. The circuit consists of some resistors, condensers, diodes
and a thyristor. This thyristor is an electronic switch, which has the same
function as the set of contacts of a conventional ignition. Below you will
find the circuit and a photo of a self-build transducer. Mind you, in case
you're planning to build such a transducer, you will have to add an external
6 V coil. (Best results came from a 6 V external coil for each transducer).
It is also possible to use the coil from the transducer of a Honda 250/400N.
In case of broken transducer(s) you can choose to build your own transducer.
You will save yourself a lot of money that way, or you can buy brand-new transducer(s),
which are still available in Germany (see below).
The electronic circuit of a 1-st series of transducer.
Mind you: an external coil should be connected to such a self-made transducer (see above).
The self-made transducer (without external coil) on both sides.
Build your own transducers: Volker Sachse (see http://www.italoclassicbikes.de/) from Germany has sent me the following information in a PDF file:
new professional layout for a circuit board. Mind you, the layout shows the bottom of the circuit board, the copper tracks !!
layout with the electronic components drawn in again, you are looking to the bottom of the circuit board !
You will need Acrobat Reader to open the file. In case you don't have it, get it for free at:
Repair: At the bottom of each transducer you will find a dark-red potting substance. You have to carefully remove this. You can
use "dimethylsulfoxid" (C2H5OS) and mix it 1:1 with "aceton" (nailvarnish remover)
(C3H6O). This mix will solve the potting substance. It is a time-consuming process and you have to be
careful you don't destroy the contains of the box and the housing. When a transducer is broken, it is mostly the coil or the
thyristor that needs replacing.
this is the coil inside the transducer
contains of the transducer
Replacement:
Make sure the replacement transducer is of the correct type (see table above).
In the US, contact Herdan, the
former importer in Port Clinton (tel. +1 610 562 3155).
Another source for brand-new transducers can be found at Morini specialist (over 20 years Morini experience)
Wolfgang Tritsch (speaks/writes several languages, including English).
Tritsch had the (improved) transducers of the 2nd series re-made. Also transducers of the 1st
series to combines with the red pick-up he had made. These transducers are € 66 (previously DM 129) each (January 2000),
a complete set of two transducers and a black pick-up is € 150 (previously DM 295).
Contact Tritsch at:
Wolfgang Tritsch, Address: Schwabenmatten 7, Place: Pfaffenweiler, ZIP: D-79292, Germany
(tel +49 7664 60300 and fax +49 7664 60555).
In Italy Delta Progetti, in Bologna (contact person) Sig. Filippini,
tel +39 051 6196355, or mobile +39 338 9600238, sells brandnew transducers (probably the red aftermarket version). They
cost € 40 each. Also new black pickups are available at € 80. Delta Progetti also sells to private people.
Latest after-market Tritsch transducer (red, number 323987) and an original
black pickup from the 1980s.
Earlier after-market Tritsch transducer.
Alternative systems There are professional alternative systems available, like the full-electronic ignitions of the makes:
"Lucas Rita". Follow the link to a new sub-page, written by Kieran,
who successfully installed a Lucas Rita set. Kieran sums up the pro's and con's of this system.
"Boyer Bransden". Follow this link to a new sub-page written by
Lars. He gives a good description on how to succesfully install a Boyer Bransden set on a Moto Morini. Boyer Bransden
have both an analog as well as a digital ignition available. Lars installed the analogue system, but there is also
information on the digital Boyer Bransden.
"MZ-b in Berlin" (in English)
produces alternative ignition systems for a wide range of classic motorbikes. They now have a system for the Morini 3½
(see the link) and also for the Morini
175cc singles like 175 GT and 175 Tresette.
"Digital Ignition!". From the end of September 2004 a
digital ignition system will be available in Germany. This system was designed by
Volker Sachse and will be sold by "KMS Motorrad".
See the system on their website and follow
>KMS-Zubehör >Digitalzündung.
Marcus Heilig from Germany has developed a new pickup for the Morini V-twin
models. Replacements for both red and black pickup are available! With these new pickups it is possible to set the timing
of front and rear cylinder seperately. This is an improvement compared to the original ones made by Ducati Elettrotecnica.
See Marcus' website (in German, but with excellent photo's
of the prototypes & ready version pickup and even a film of the testing).
In depth technical article in German on Morini pick-up operation, design, parameters written by Franz Grabowski.
Also contains info on ignition curve and few hints how >to improve the Morini ignition
An article treating on ignition curve, written by Gunnar Lerch.
German version .pdf format English version .pdf format (translation from German to English by Peter
Cloer and Gunnar Lerch).
To get Acrobat Reader to read the .pdf files, follow this link
To rewind the 12 Volt, 100 Watt alternator look at this schematic
diagram for number and direction of inner and outer windings. Wire used is 0.8mm
pu-insulated copperwire. The diagram is drawn by Lars Bendsen from Denmark.
Note 1: later models with an electric starter have a "heavier" alternator (180 Watt?);
Note 2: to rewind the seperate ignition coil
follow this link to a sub-page. (The ignition coil is the yellow one shown on the photo's on this page).
Note 3: the offroad models Kanguro and Camel have a different alternator of both 12V (directly to headlight)
and 6V (rest of the bike). The conversion of the 6V alternator of the Camel/Kanguro models can be done as described
by Werner Wilhelmi in this article.
The 6V/12V combined alternator as on the Camel and Kanguro ...
... and a 12V alternator of later models. On earlier alternators there is no seperate earthwire (white).
This particular alternator could well be from an Excalibur 350/501, as the red pick-up wire is missing (Kokusan
ignition!)
In case the electronic rectifier on your Moto Morini has broken, you can find some information on this part below. Soon a
list of electronic components will be added. There are two different rectifiers known used by Moto Morini for the V-twin
models (and singles). Below you can find information on the 12 Volt version used by Morini BEFORE the introduction of the
e-start motorbikes.
All I have available on the rectifier for the e-start models is a hand-drawn
circuit.
The original rectifier on the pre-electric start models.
The 2nd model for the e-start models
Both sides of the circuit board, with the electronic components drawn in.
The circuit of the rectifier for the e-start models.
Volker Sachse (see http://www.italoclassicbikes.de/)has built a Morini rectifier,
see circuit, etc.. Detailed photo's will follow. After download, the file can be opened with Adobe Acrobat Reader.
See the link elswhere on this page to get free Acrobat Reader.
