electronic ignition... no spark

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Daggs
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I'm glad you (seem) to have resolved the issue. But those magnets are usually fixed with epoxy glue and a screw, for very good reason.
Plus you have now moved them closer to all the coils, running a risk of fouling. You could have just gently bent the fingers up, they will take a gentle tweak.
I would have simply adjusted the pick-up position!
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HxPaul
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Daggs wrote: Sat Dec 08, 2018 9:18 am I'm glad you (seem) to have resolved the issue. But those magnets are usually fixed with epoxy glue and a screw, for very good reason.
Plus you have now moved them closer to all the coils, running a risk of fouling. You could have just gently bent the fingers up, they will take a gentle tweak.
I would have simply adjusted the pick-up position!
+1 Also you didn't put any loctite on the threads of the screws,so when the card get squashed over time (as it certainly will)The screws will come undone
johnny650
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Daggs wrote: Sat Dec 08, 2018 9:18 am I'm glad you (seem) to have resolved the issue. But those magnets are usually fixed with epoxy glue and a screw, for very good reason.
Plus you have now moved them closer to all the coils, running a risk of fouling. You could have just gently bent the fingers up, they will take a gentle tweak.
I would have simply adjusted the pick-up position!
Daggs I have to take issue with your comments which in every respect are incorrect.

1. The Flywheel magnets were NOT stuck with epoxy or any other sort of glue . ;)

2. There is no risk of 'fouling' as you put it because I tested clearance before starting the engine (watch the video )

3. The absolute no-no is bending the magnet fingers. This will not work and will definitely run the risk of breaking the fingers off or damaging the face of the pickup.

4. The fingers need to be parallel with the face of the pickup NOT at an angle or they will not trigger a spark .....Bending the fingers is just a bodge. Shimming the magnets is the correct way to adjust the pickup gap.

5. It is not possible to adjust the position of the pickup which has both a screw fixing and a locating dowel to prevent it being moved .
The only way you could 'move' the pickup would be to elongate the pickup screw hole into a slot and also file off the dowel which keeps the face of the pickup square to the magnets ;)
johnny650
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HxPaul wrote: Sat Dec 08, 2018 10:00 am
Daggs wrote: Sat Dec 08, 2018 9:18 am I'm glad you (seem) to have resolved the issue. But those magnets are usually fixed with epoxy glue and a screw, for very good reason.
Plus you have now moved them closer to all the coils, running a risk of fouling. You could have just gently bent the fingers up, they will take a gentle tweak.
I would have simply adjusted the pick-up position!
+1 Also you didn't put any loctite on the threads of the screws,so when the card get squashed over time (as it certainly will)The screws will come undone
The screws were loktited I just didn't show it in the video like I didn't show a lot of things. I had to edit out more than half the video in order to get the length down to upload it. The finished video was made up of a total of 5 shorter videos and took hours to convert and edit

What amazes me about this forum is that over the past few weeks neither of you 'experts' have offered me a single sensible solution to my no spark issue ........but boy are you both quick to post and find fault and critisise someone elses efforts in finding a workable solution :D

Neither of you thought that mis adjustment of the gap between the magnets and the pickup could be the reason for a no-spark

This solution is simple and straightforward and will help countless other Lambretta owners to fix a no spark issue when every other ignition component has been exhaustively tested and confirmed working.

Over the past few weeks I have not found a single mention of adjusting the pickup gap in this way to cure a no spark issue anywhere. There isn't a single video on youtube or anywhere else specific to lambrettas not even on the fantastic MB site. There is no mention in Stickys manual or any other Lambretta workshop manual about adjusting the pickup gap or testing the gap or what the gap should be

Why not show a little appreciation for a useful tip for the Lambretta community instead of constantly finding reasons to critisise.
holty
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im pleased you sorted it out pal, these issues are a pain with electronic ignitions, I did suggest flywheel was the fault or certainly worth trying, ive just fitted a full tambs internal and external kit so my mate will have 2 systems, if one fails he can switch to the other, belt and braces, well done for getting a solution.
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HxPaul
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Adam_Winstone
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Well done for sticking with this and getting it sorted.

Pickup alignment and gap is actually a reasonably common problem but will normally show itself as a poor signal that causes your ignition timing to wander with revs. Anthony Tambs has now cut slots into the face of his flywheel to be able to measure the air gap but there is still no means of adjustment unless you fit one of his external pickups, which make this very easy. Yep, you're right that you can oversize the screw hole through the pickup base and you can slightly oversize/drill the hole in the laminates so that there is an amount of adjustment on the dowel, but a better means of adjustment would be nice.

One thing that I've come across a number of times recently is the splaying of laminates on aftermarket stator bases, where the laminates splay and cause the face of the pickup to angle away from the flywheel face, with the top trigger moving quite a distance back from the flywheel. Its a shame as this is just a poor quality of manufacture issue, whereas even old original points stators have a rock solid laminate core after decades.

Anyway, well done for getting it sorted as a I'm sure that many of us have been sharing your frustration with this, having suffered similar in the past.

Cheers
Daggs
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Johhny650

You think I was having a dig. I wasn't.

In answer too your 5 points

1) Every 12v flywheel I've ever seen the magnets have been epoxy glued.
2)I said "risk"
3)I've bent 'em and it's fixed the issue. You think this is a "bodge" but you don't think putting card under the magnets is !
4)Disagree.
5)It is, if you try.

Oh! and point 6 ( I know you didn't have one) You had plenty of help coming at you. I've previously complained on here that when too many get involved the OP ends up with a load of contradictory suggestions.

Nonetheless, I'm pleased you've got the scoot going. You've had a frustrating time of it. But I suspect you've learned a lot. :)
Martin20
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Well done with getting this sorted Johnny! Following this thread has been like trying to learn a foreign language for me, electrics being probably the subject I have the least understanding of! My scoot would have been in the skip weeks ago! Great that you stuck with it though, and got it sorted. Will be interested to hear how bike runs when you get it back on the road.
All the best
Martin
firekdp
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johnny650 wrote: Fri Dec 07, 2018 8:55 pm I did find this similar post by Fast n furious on LCGB (scroll down to last post )
http://www.ilambretta.co.uk/forum/viewt ... est#p96325
Interesting read, but I'd disagree with a lot of it.
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