Vespa/Lambretta Scooters. Ignition question.

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Tue 26 Feb 2008 10:03
Vespa/Lambretta Scooters. Ignition question. - Petel
This is a general question which does not relate to any specific model or engine size of the Classic Vespa and Lambretta scooters.

These scooters of the 60s and 70s generally had static ingition timing. Can anyone please advise if, with the advent of electronic ignition, any provision was made for the inclusion of some form of advance/retard to the system?

If so, a rough outline of how this was done and if it was provided by the manufacturer or as an after market add-on?

Thank you.

Edited by Dynamic Dave on 26/02/2008 at 12:18

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Tue 26 Feb 2008 12:46
Vespa/Lambretta Scooters. Ignition question. - Chris S
Lambretta scooters went out of production in Italy in 1971 - an Indian made model was in production untill fairly recently.

As far as I'm aware it was just a clone of the original.

The points were mounted on a static plate behind the flywheel generator, I think it had the copper-windings on as well.

I don't think it would be possible to make the plate mobile without major design changes.

Edited by Chris S on 26/02/2008 at 12:48

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Tue 26 Feb 2008 14:24
Vespa/Lambretta Scooters. Ignition question. - John S
Trip down memory lane here. I used to own a 1959 Li150. Chris is right. The Lambrettas of the 50's/60's ( I know nothing about the Indian models) used a permanent magnet flywheel, copper coils and points mounted on a plate behind the flywheel. The plate could be rotated to adjust the timing, but there was no advance/retard mechanism. This is not uncommon on small two-stroke engines. Electronic ignition has made its way into the market on most small engines, not only motor cycles but also mowers, strimmers etc. Most seem to simply avoid the use of points and still don't have advamce/retard mechanisms.

JS
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Tue 26 Feb 2008 19:45
Vespa/Lambretta Scooters. Ignition question. - bathtub tom
I can't recall any two-stroke having an advance/retard mechanism.

Perhaps one of the more knowlegable BRs can explain why?
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Tue 26 Feb 2008 20:41
Vespa/Lambretta Scooters. Ignition question. - Another John H
It's my understanding that vacuum advance is an economy device, and that in addition to the scooters mentioned above, some FIAT cars from the 60's didn't bother with it either - the timing is set as near as for optimum power, but lacks the advance needed for best use of a light throttle.

I don't think the Italians do part throttle :)
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Tue 26 Feb 2008 21:28
Vespa/Lambretta Scooters. Ignition question. - Railroad.
The points are simply a means of switching the ignition coil's primary windings on and off. Electronic systems essentially use transistors rather than mechanical points to switch the coil.

The biggest problem with a points system is that the dwell angle (the number of degrees the coil is switched on) remains the same regardless of engine speed. This is known as 'Constant Dwell', and is also exactly what you don't want, as the spark gets weaker as the engine speed increases.

Electronic systems can vary the dwell, and increase it with engine speed, so that a bigger and fatter spark can be achieved, especially at high engine speeds when it's really needed.
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Thu 28 Feb 2008 11:13
Vespa/Lambretta Scooters. Ignition question. - Petel
Thank you for your replies.

I have now established that there are adv/ret options available for these machines. It would appear that the Indian manufactured Lambretta introduced this option at some point and that there are now, UK manufactured after-market kits available.

If anyone here has any knowledge off, or hands on experience of installing and of the performance/reliability of these items, the input would be welcomed.
Thank you.
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Thu 28 Feb 2008 11:24
Vespa/Lambretta Scooters. Ignition question. - bathtub tom
Try this place:
www.bedlam-scooters.co.uk/

There's also a place in Weston-Super-Mare.
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Thu 28 Feb 2008 11:48
Vespa/Lambretta Scooters. Ignition question. - mike hannon
I can't help following this thread, although - sadly - I don't have anything useful to contribute.
It's just that there's a young guy along the road from me, here in deepest France, who runs a restored Lambretta LD, complete with matching sidecar! By the smell of it, he runs it on about 16 to 1 mix petrol/castrol R.
I'd love to ask him if he can help with the question, if I can only figure out how the French describe 'ignition advance-retard'...
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Thu 28 Feb 2008 11:50
Vespa/Lambretta Scooters. Ignition question. - mike hannon
ps: by coincidence I have friends who live right opposite what used to be the Lambretta museum/workshop in Weston - I think it's now defunct, or at least moved away. I watched them loading old scooters and bits into a van last August.

Edited by mike hannon on 28/02/2008 at 11:51

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Thu 28 Feb 2008 12:06
Vespa/Lambretta Scooters. Ignition question. - bathtub tom
It would have to be an enormous van. Did you ever go in there? It was really a shop, but they had so many machines, they didn't mind people wandering round. It brought back memories for ole gits like me - I'd forgotten they used to race them, until I saw one in there. They were very friendly, and didn't mind chatting.
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Thu 28 Feb 2008 13:11
Vespa/Lambretta Scooters. Ignition question. - Petel
You are very welcome Mr Hannon. The LD, as I recall, had a motorcycle type engine and I believe it was a four stroke. Not many left now, with or without a sidecar.
Rgds.
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Thu 28 Feb 2008 14:21
Vespa/Lambretta Scooters. Ignition question. - bathtub tom
IIRC the LD was the fourth incarnation, had shaft drive. All were two-stroke.

There's an owners' club site:
www.lcgb.co.uk/
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Thu 28 Feb 2008 16:15
Vespa/Lambretta Scooters. Ignition question. - jc2
LD were certainly two-stroke-ran on petroil.
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Thu 28 Feb 2008 20:19
Vespa/Lambretta Scooters. Ignition question. - Pugugly
Very interesting article in Wikipedia......Lambretta's demise linked to the failure of British Leyland - you learn something everyday.


en.wikipedia.org/wiki/Lambretta

Edited by Pugugly on 28/02/2008 at 20:20

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Thu 28 Feb 2008 23:25
Vespa/Lambretta Scooters. Ignition question. - Petel
So the LD was two stroke, must have been the motorcycle type engine that threw me.
Thanks.

Now, how about this adv/ret kit please. Anyone ever used one?
Thanks and regards.
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Tue 14 Apr 2009 20:34
Vespa/Lambretta Scooters. Ignition question. - Phil A
Hi to all , I own an LD 150 and have owned it for the last 35 years so know it inside out. This is definately a 2 stroke engine either 123 or 148 cc running on 16 : 1 petrol/oli ration ie 1 gallon of petrol to half a pint of oil. This model has a marrelli or Filso flywheel and HAS an automatic advance retard mechanism in the form of 1 or 2 bob weights that expand when the egine is revved over approx 1200 rpm to advance the ignition, It works very well and is retarded for easier starting and ticking over, hope that answers most of the questions !!
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Wed 15 Apr 2009 20:35
Vespa/Lambretta Scooters. Ignition question. - John S
Phil

That's interesting! Looks like they went back to fixed timing when the LD changed to the Li/Tv models in the late '50s. My '59 Li certanly had no advance/retard machanism.

JS
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Tue 11 Jul 2017 18:33
Vespa/Lambretta Scooters. Ignition question. - ELJ
Hi to all , I own an LD 150 and have owned it for the last 35 years so know it inside out. This is definately a 2 stroke engine either 123 or 148 cc running on 16 : 1 petrol/oli ration ie 1 gallon of petrol to half a pint of oil. This model has a marrelli or Filso flywheel and HAS an automatic advance retard mechanism in the form of 1 or 2 bob weights that expand when the egine is revved over approx 1200 rpm to advance the ignition, It works very well and is retarded for easier starting and ticking over, hope that answers most of the questions !!

Hi Phil

I also own an LD150 and I am having serious problems with the timng, your advice would be appreciated. Have you an e-mail address I can contact you on?

Thanks

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Wed 12 Jul 2017 13:29
Vespa/Lambretta Scooters. Ignition question. - Peter.N.

I had a Vespa in the '50s and my wife had a Lambretta in the '60s and they both had what I would call a standard 2 stroke set up. I now have a chain saw and various other implements and the 2 stroke set up is still the same except for electronic switching on the coil.

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