125 WITH NO SPARK

Lambertini era singles (125 and 250 - half v-twins)
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hello Bill,

I cannot go much further with mine until the stator comes back, so will have to sit on my hands again, I am considering buying a new pickup and transducer from Nuova Ray they are quite expensive compared with the blue ones from scooter shops and eBay, but the problem with these items is that we don't know where they are made, some are coming from China others from India so how good actually are they inside. Like many other cheap Chinese copies they even have the original makers name on them (Ducati) I suppose its like cheap fake mobile phones nice shiny case, crap electronics inside because they all want something that looks the part with an expensive name - for nothing. I have chucked so much money into this project now that a few more Euro's for a good set may well be worth while and it won't break the bank.

Regards
Leonard.
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themoudie
Posts: 130
Joined: 13 Jan 2007 21:24
Location: Perthshire

Re: 125 WITH NO SPARK

Post by themoudie »

Good morning Leonard,

I am not spending any money on components until I have proven that there is something faulty, with a combination of those that I already have. Costs may not break the bank, but I don't wish to acquire more "useful" shelf ornaments!

I will post further, once I have some definitive information.

Good health, Bill
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hi Bill,

I rather fancy that a 125H may well be a useful shelf ornament in itself! That said I will continue to try and resolve the problem, a friend who has done a lot of work with electronics in the forces made comment that the components should 'shake hands' in other words be compatible, if the pickup coil is not sending the correct signal to the transducer at the correct time then an issue will occur. Which is why I was considering a matched pair of items from a reliable manufacturer, rather than eBay for example. I agree that spending more money on this is perhaps unwise in your case the only way really is a process of elimination to find where the fault is and then using what's left over that works.
I think you mentioned earlier that the 125H was for your daughter in-law to learn on but then she will probably want something bigger and better in my case it was for a keeper so I have to view it from a different angle, if I had bought this for such a purpose as yours it would have been long gone by now!

Please let me know if you find a solution and I will do likewise.

Regards
Leonard.
andygrew
Posts: 5
Joined: 04 Jul 2020 22:18
Location: Martock, England

Re: 125 WITH NO SPARK

Post by andygrew »

Hi Guys,

Just logged into the forum after a long absence and am sorry to learn that you both still have problems with the 125H.

First let me assure you that the 125H does run, my grand daughter has been using mine for a year now with no issues and I have also ridden it and found it a very pleasant little bike. A previous owner also used it on a Morini Club track day - god forbid!!
It didn't run when I bought it but replacing the Ducati transducer with a spare 323921 I had in stock cured the problem.

Reading through your posts, I think your ignition may be too advanced and when the box switches to full advance at about 2,500 rpm this is far too much and the engine will not run properly. It should be noted that these boxes do not have an advance curve, they just switch to full advance in one go.

I had these boxes on my Ducati and this switching made running round town very unpleasant, and was also a contributary factor in the crank problems experienced on early 860's.

If you need any measurements/ diagrams or pictures from my bike to confirm any detail you are not sure of please feel free to ask.

Regards

Andy
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hello Andygrew,

thanks for the further information as always its useful and will be put on file, I have had many differing opinions as to the 125H problem and as to how the ignition actually works, or does not work in most cases.

I have a contact in Germany who also sent me some details, apparently there is a base setting which is achieved by setting the piston at TDC both valves closed (the firing stroke) then turn the flywheel rotor back to align the ANT mark with the centre camshaft or the timing mark at 12 o'clock on the crank case. At that point the two notches on the flywheel/rotor must align with the two ridges on the black pickup. The engine should then start and run - advance and retard is then corrected by moving the stator plate in the slots, preferably using a strobe light, when strobed the ANT mark should be in line with the centre of the camshaft. However, do not expect to see the timing ANT mark slowly move it does not, it jumps to the previous setting as set with the strobe and below about 2000 rpm it reverts to its retarded setting for tick over and starting - to avoid kickback.
One area of disagreement is that the transducer controls advance and retard my German contact says this is only effected by the black pickup, the transducer is only really a capacitor/coil which is charged by the ignition coil on the stator plate and the black pickup tells the transducer when to fire the plug. Now before I am shouted down again, please note I am no expert and for the information of others have relayed this information as I was told. I have not tried this theory as yet but hope to do so very soon.

Regards
Leonard.
User avatar
themoudie
Posts: 130
Joined: 13 Jan 2007 21:24
Location: Perthshire

Re: 125 WITH NO SPARK

Post by themoudie »

Aye Andy and Leonard,

Thank you for your further input Andy and Leonard, the detailed set-up notes that your German contact supplied .

However, I am unclear how after "... setting the piston at TDC both valves closed (the firing stroke) ... " I " ... then turn the flywheel rotor back to align the ANT mark with the centre camshaft or the timing mark at 12 o'clock on the crank case."

As the flywheel rotor is keyed to the crankshaft, it is not possible to set the piston at TDC and then move the flywheel rotor, as the TDC position will then be lost! :? :? :?

I suspect that after "... setting the piston at TDC both valves closed (the firing stroke) ... " I need to then adjust the stator plate so that the " ... two notches on the flywheel/rotor must align with the two ridges on the black pickup.". Then use a strobe to to adjust the ignition advance to 36°BTDC @6,000rpm.

The sentence "However, do not expect to see the timing ANT mark slowly move it does not, it jumps to the previous setting as set with the strobe and below about 2000 rpm it reverts to its retarded setting for tick over and starting - to avoid kickback." makes absolute sense.

As does "One area of disagreement is that the transducer controls advance and retard my German contact says this is only effected by the black pickup, the transducer is only really a capacitor/coil which is charged by the ignition coil on the stator plate and the black pickup tells the transducer when to fire the plug." This is also my understanding and the reason why my original trigger coil was replaced, as the negative wave side of a full wave signal from the coil was not shown, when the triggercoil was attached to an oscilloscope.

I have yet to get dynomometer time to "run" the ignition without actually running the engine and "The Minx" lies under a cover at the back of the workshop, whilst the Ducati 450 puts in the miles.

The Moto Morini 250 single in Pugh's auction last week, didn't sell, either through lack of interest or insufficient funds! Probably the same fate for 125H machines. :( Here is the link: HJPugh_auction_Moto_Morini_250_single

Good health, Bill
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hi Bill,

probably a bit was lost in translation, my German is only basic, but I think as long as the timing is set on the compression stroke with the ANT mark aligned with the cam centre and then as you say move the stator plate so as to align the two ridges on the pickup with the two engravings on the rotor the timing is then at its basic setting and the engine should run and then final adjustment made with a strobe light.

My 125H is currently under wraps to, I managed to put my back out recently, so working a around a bike has not been possible and I am in the process of making some rear sets for it as no kits are available - it came with clip-ons and a top yoke without handle bar clamps so the riding position was not really comfortable.

I hope you are successful with the rolling road idea as it should show up any problems that cannot be identified when static.

I fear Morini's were never really a top seller in the UK especially the classic stuff and with spares becoming scarce it will not help matters, I had some bad news recently that the Dutch club is disbanding mainly do to a lack of interest and an aging membership with no new members joining. I suppose the young want reliability and performance instead of crawling around old bikes trying to get them to run.

Best regards
Leonard.
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hi Bill,

Had a discussion with Bradford Ignitions today, they have run my ignition on a test rig up to 12000 rpm and cannot get it to advance at all the pick up, transducers and coils on the stator all appear to be working fine and they are at a loss as to what the problem is, they have not come across this particular ignition before (no surprise there) but feel the problem could be something to do with the rotor itself not switching the ignition to its advanced stage, there is a non - magnetised stud and a cut-out section inside the rotor magnets that they suspect is the switch but does not appear to have any effect at all, I will try and locate an alternative rotor to see if there is any difference - but at 40 years old pigs may fly.

They are sure its not an electrical issue but possibly something mechanical.

So another fruitless and expensive exercise in the 125H saga and where I go from here I am not sure.
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themoudie
Posts: 130
Joined: 13 Jan 2007 21:24
Location: Perthshire

Re: 125 WITH NO SPARK

Post by themoudie »

Good morning Leonard,

Thank you for your update. I am very sorry to read that Bradford Ignitions appear to have drawn a blank as to the cause of our mutual problem. :evil:

Whilst I am not at an advanced stage, or thrown more cash at the The Minx, I am investigating the possibilities of using a more up to date, 4 stroke ignition system. Even though it would appear that there is nothing wrong with your electrical components, they appear not to be compatable or triggered by the rotor cutaways that effect the magnetic fields triggering the spark advance and retard signal to the CDI circuit; if I understand your message correctly?

If I make any progress, I will update this thread, providing specific information.

Good health, Bill
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hi Bill,

yes they seem to think the problems is 'mechanical' the triggers being inside the rotor and not on the stator plate, I am not sure if there is anything broken in the rotor or missing, I have two rotors and they both look the same, that's not to say they are both OK though.
I am hoping to get a picture of a new one as a comparison and a new rotor may be the final avenue in this saga if that doesn't work then I don't know where to go from here.

The new blue transducer works OK under test and so does the black original.

I certainly would be interested in anything you come up with in regard of a new system, please keep me informed on that. I am losing my sense of humour with the 125H and will probably put it under wraps now for the rest of the winter and decide then what to do in the spring.

Regards
Leonard.
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themoudie
Posts: 130
Joined: 13 Jan 2007 21:24
Location: Perthshire

Re: 125 WITH NO SPARK

Post by themoudie »

Aye Leonard,

It's called a morte cloth! :evil:

I will be giving my rotor a thorough inspection, but insofar as I am aware there are no moving parts, only the spinning of the rotor on the end of the crankshaft. I can hang 1lb weights off the individual rotor magnets, so I don't think that weak magnetic fields are a problem. Maybe the " non - magnetised stud" has become magnetised? :? Quite how to de-magnetise it could prove interesting! :wink:

Like yours, both the OME black Ducati Electronica CDI/HT module #323921 and the replacement blue Ducati Electronica CDI/HT module #32398 112 are working. Whilst the original Low Tension Coil (LTC) supplying the vAC to the CDI/HT module is in good working order, as was the Indian replacement LTC that I fitted. The return to the OME LTC was because of it's better quality of construction.

The fly in the ointment appeared to be my OME Trigger Coil (TC). Whilst its resistance was within tolerance, once under load it was not producing the lower half of the sine wave, therebye not sending a full signal to the CDI/HT module circuitry and causing the ignition to advance as the engine rpm was increased. The Indian pattern TC also appeared to be working, with both an acceptable resistance value and a full sine wave signal. Again, this was substituted for a better quality OME type Ducati Electronica TC that works on Lambrettas, BUT and this is the the BIG BUT, the signals they are producing may not be compatible with the CDI/HT modules circuitry, hence the lack of ignition advance. The OME TC are no longer produced and are all but impossible to distinguish from Indian/Chinese, faux products. :cry:

So, I am working on three options:

1. Complete replacement of the ignition components, with more modern, matched components.

2. Set up a trigger on the nearside end of the camshaft, as fitted to all other Lambertinni, Moto Morini engines, with a 6 pole alternator supplying 12v to a battery and coil ignition, as on my Ducati single.

3. Fit an alternative engine!

Having read through Bradford Ignitions website, his comment about black TC causing engines to splutter and stutter, when not functioning correctly rings bells. But, again he appears to predominantly be dealing with 2 stroke engines, not requiring the ignition advance of our 4 stroke engines. The fact that he is left scratching his bonce, doesn't bode well for a simple diagnosis and fix.

I'll keep you posted, but this is not top of the list at present! :wink:

Good health, Bill
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hello Bill,

a morte cloth indeed, perhaps one day someone will find it in my garage under a dusty sheet and long after I have gone and sell it on eBay as a barn find, then some other poor soul will take it on and try to get it running.

I think Bradford Ignitions probably did all he can with it and he is not the first one to try and sort it out, its left most people 'scratching their bonces' including me. Its a simple enough system compared with modern ignitions but does not work.

He was convinced it is not an electrical problem all the tests on the coils and components were OK but as we both know there are many expert's out there and all with different opinions and you know what they say about opinions.

I too am not sure about the rotor causing the problem but anything is possible and am currently hoping to find an unused one to try, trouble with all this testing, rewinds and replacement of parts is that its just chucking good money after bad and with no result. Unfortunately I have found that the stator plates that looked possible did not fit the crankcase or behind the rotor, or did not have charging coils for the other electrics. (racing stators).

Realistically I think your idea of a replacement ignition system of some sort is the only practical option before radical expensive changes to the engine or a replacement engine are to be considered.

Please let me know if you come up with a solution.

Regards
Leonard.
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themoudie
Posts: 130
Joined: 13 Jan 2007 21:24
Location: Perthshire

Re: 125 WITH NO SPARK

Post by themoudie »

Aye Leonard,
Please let me know if you come up with a solution.
Nae bother.

Good health, Bill
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hi Bill,

no problem, have a good Christmas if we do not communicate again.

by the way there are a couple of engines on eBay in Italy if you really wanted to try a radical modification.

Regards
Leonard.
125H
Posts: 76
Joined: 30 May 2018 18:36
Location: Loughborough UK

Re: 125 WITH NO SPARK

Post by 125H »

Hello Bill,

a little more information from across the channel - if you look inside the rotor there are two pointers on the magnets that correspond with the A mark on the outside, apparently these control the advance and retard. One of the pointers ( for the want of a better word) is for starting and tick over, the other controls normal running. The two pointers if you note line up with the two silver contacts on the pick - up (the black thing on the stator) and send signals to the pick - up. Sometimes I am informed the pointers can get damaged of even broken off which will then stop the ignition advancing.

Another issue the correct rotor must be fitted, dependant on the model of the 125H my machine is the earlier one, series 1 with the old rectifier which can be opened and acts as a fuse box. The later version has a sealed rectifier and I suspect yours may be the later model which users a rotor with a part number 31 96 91 (possibly) also the correct pick - up must be used to time with the pointers in the rotor.

So just a thought, does your rotor have the two pointers, not damaged is your pick - up correct for the year.

I am still waiting the return of my ignition from the 'expert' at Bradford Ignitions who failed to find any faults so will be checking these points over when it comes back.

Regards
Leonard.
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