Substitution with 'known good' components is sometimes the only way to diagnose something. I've lent a working twin cylinder pickup to a couple of people that proved that was the issue though their unit looked fine.
Not many 125 Hs around in the UK though as you say. I nearly bought one off evguru for my lad to use for 'racing' May have dodged a bullet.
Beer is good, but I find a decent Italian red plonk more efficacious in this weather.
It may well be, but its easy to collect lots of useful or useless ornaments in the form of components that did not cure the problem.
The 125H was never officially imported into the UK so knowledge and spare parts is rare I made a rookie mistake when I bought mine, the sump was full of oily sludge and the fuel tank with the remains of old lawnmower fuel. Instead of draining it all down and trying to start it I embarked on a restoration project, if I had done some research and tested the engine it would have been back on the auction site before the restoration was started.
So I now have a very pretty Italian lightweight that does not run as it should and having just about exhausted all expert advise and spent a load of cash on testing only to be told what I already knew its difficult to know where to go from here. I have a few last ditch things to try but am not hopeful unless I can find a complete new system that will fit. There are options of course involving some quite serious and expensive conversation to a modern adjustable advance system but it would probably require machining of a new rotor to fit the crankshaft and how much money is it worth throwing at a 125H.
I would agree about the Italian red plonk, I have a nice Chianti warming by the fire.
I used Google Lens on a smart phone to translate the article https://www.motomoriniclub.nl/zuendung.pdf to English and I can see that this gives a good description of the importance of the 1.38V trigger point voltage and how it occurs earlier as engine rpm increases. You can use Google Lens to give a voice-over description too. I quite fancy a 125H but the problems you guys are having has put me off a bit. Ian
The 125H problem is not just within the UK I have made quite a few contacts in Germany and the Netherlands with very similar issues, although some owners have no problems at all with them.
One German contact is looking at using a modern Ducati single ignition/generator unit and I await with some interest as to how he gets on with that. Personally I have wasted time and money having my ignition tested by so called experts with no result, so yes you probably did miss a bullet by not buying into one, although I doubt very much that Paul would sell you a crap bike that did not run, its not worth his reputation.
Personally I think the problem may be one of assembly that is to say setting the static or base timing, according to the Germans this is achieved by setting the piston at TDC on the compression stroke both vales closed PMS mark aligned with crankcase mark, then turn the engine back to the ANT mark or A mark in the case of an early bike. Hold that position and then move the stator plate to align the two scribe marks on the rotor with the two lines on the black pick up, the engine should then run - hopefully! Final adjustment is made with a strobe light. I did a quick check with a timing disc and this appears to give 32 degrees BTDC. This is of course in theory, problems may exist in the pick up not aligning with the two magnetic triggers in the rotor, I was told that sometimes if a non - standard pickup was fitted that it may require shimming to get the right switching for advance, again more theory. My 125H is under wraps its too cold for an old bugger like me to be out in the garage, but once things warm up I am certainly going to look at the static timing to see if it will run, if not more investigation will be required.
There are 125H problems all over the place, as you can see from this forum.
I have done very little with mine over the winter but just getting back to it now, mine is an early model and the electrics on the later bikes are slightly different.
No one seems to know what the problem is, I thought it maybe crankshaft related but I have replaced all the bearings so movement there should not effect the timing. Personally I feel its a problem within the stator and its relation to the transducer, pick - up and magnetic triggers in the flywheel, I spent quite sometime getting these items lined up with shims but to know avail. The ignition system is probably a 'knock off' from a two stroke scooter done on the cheap by the factory. To that end I have an electrical engineer looking at fitting a 4 - stroke programmable transducer with some other modifications that I don't quite understand. I am a points and magneto man and all this leaves me cold. Be careful of spending money on this ignition project, to date I have wasted about £200 paying so called experts to test and repair the system only to be told it does not advance - something I knew already. I hope the current man can come up with an answer and if so will post the findings.
Also I would mark the ignition timing as is before you disassemble it, there is also a base setting that does not seem to appear in any of the manuals it involves setting the piston at TDC on the firing stroke with both valves closed, the PMS mark on the flywheel should then be aligned with the timing mark at 12 o'clock on the crankcase, then move the flywheel to the ANT mark, at this point the two fine scribe lines on the flywheel should align with the two lines on the pick - up you can see this through the slot in the flywheel, if not move the stator until they do, any final adjustment is made with a strobe light once the engine is running - good look with that! The ignition has two fixed settings controlled by the flywheel one for starting and tick over (with no kickback) and it should then advance to normal running at about 2000 revs, however mine will not make the jump to advance, it is a jump and not a gradual increase like the V twins which are different. Running the engine in this retarded state will cause overheating and sluggish performance, I do not know why Morini opted for this ignition system probably cheapness and availability its clearly for a two stoke and two strokes tend to run retarded anyway so that may be the root cause.
Hello All with a 125H as you may know some of us have experienced ignition problems with the 125H I appear to have recently resolved mine with the help of an electronics expert. Its now finally running as it should, initially I used shims to make sure that the pick - up was in line with the magnetic triggers inside the flywheel mine was not and used three shims. However the problem was not cured. I then got in touch with Mr Anthony Tambs who runs Scootronics in Stafford. He put my stator and flywheel onto his test rig and the oscilloscope indicated no advance as before and as found by other so called experts. However Mr Tambs was able to identify the problem it was one of polarity it appears that the pick up or its wiring may have been replaced wrongly and after a temporary fix to the wiring the oscilloscope was indicating the timing was in fact now advancing and later refitting to the engine proved it now works.
Mr Tambs also makes his own range of pick ups and transducers which I shall be fitting to my Morini.
If anyone still has a problem give him a call on 07971 475134 or email anthony.tambs@gmail.com his website is called Scootronics.
He is a real Gentleman, Now I am not guaranteeing that his fix will work with all 125H's but it did with mine so its perhaps worth giving it a go.
Leonard,
Thank you for the detailed resolution and for the contact details which will help others in future.
What's left for you to do before you can ride your 125 reliably?
now I have the engine running I have to attend to just a few items that were put on the back burner until that was the case. I arrived at a point where I was not going to spend any more cash or time until the engine worked and it almost went back on eBay!
So I have to fix a small leak in the petrol tank which I will have done professionally and I am still working on the footrests, brake and gear lever. The originals did not come with the bike and a previous owner had fitted rear sets which did not work too well so I am currently modifying them which is not easy as no one makes a set for a 125H.
I would hope to get it all done by mid June or early July and the engine will then require some running in as I did a complete rebuild on that including a new piston and re - bore.
If I get it done earlier will let you know, my advice to anyone buying a 125H or indeed a Morini is to make sure it runs before you part with any cash as I rather fancy that there is a lot of rubbish out there and you may end up with a saga like mine, I made that rookie mistake and remain wise after the event. If it runs alright then you will probably be OK the main problem seems to be retarded ignition which will cause over heating and in time the engine will lose power, until it cools again. The ignition can be checked and adjusted and the importance of polarity of the pick up is clear and the alignment of the triggers and pick up which I have previously described. Why these things change remains a mystery, perhaps the wrong parts where fitted or a wire that came off was not put back correctly or the laminating that supports the pick up may have compressed over time but that's all conjecture.
A word of caution! Pick your expert, there are a lot of them about who do not know what they are talking about in connection with Morini's it had taken me a long time to find Anthony Tams but he is a real expert with electronics.
May have dodged a bullet.