Electronic kit failed already?

[coaster]

I'll second the reference to Anthony Tambs on FB, the guy has gone deeper into the workings of Lambretta ignitions than anyone and is I believe not far off producing his own system. Apparently the problem with testing the pickup using an ohms meter is that it doesn't really tell you anything. The pickup consists of 2 coils connected in series and each coil has a resistor across it. When you connect a meter, all you are doing is measuring the resistance of the resistors. You need to use a 'Reactance' meter to measure the reactance of the coils. That said, pickups don't fail as often as the LT coil which can fail due to the insulating coating on the windings chaffing away resulting in a low resistance value. Or the windings which is made from thousands of turns of incredibly fine wire breaking from vibration. With your meter connected on ohms across the green and a good earth, you should see at least 450 ohms and perhaps as much as 500 ohms (BGM) try taping the coil winding with something non-conductive (wooden dowel, paint brush handle etc.) obviously the reading should remain steady.
During manufacture, lacquer is applied to bind the coil together, I unwound a faulty coil once in a vain attempt to find a break and noted that the lacquer had been applied in a very haphazard fashion. there would be dry patches going on for layer after layer. I had a go at winding my own lighting coils a few years ago and bought a jar of coil lacquer which I have used since to soak the coil windings of all my stators (currently using BGM). I also use araldite to secure all the connections and wires so that absolutely nothing can move.

Good luck

Colin

[eden]

They can fail very quickly,
Last weekend I had a new stator fail after less than 200 miles, it was a reworked one from my mate Mr Tambs.
It really is just luck of the draw if they fail or not, if they don't fail quickly they normally last a long time.
last weekend mine ran well over the 180 miles to Mersea Island but before I got off the island I had problems with it, it wouldn't rev over 5700 rpm, I did manage to get home on it, just a lot slower than intended

I did change the CDI, lead and plug cap on the way back to rule them out, I also had a spare stator with me but as we were daytripping I couldn't be arsed to change it as it was still running in a fashion.

[Chris in Margate]

Yep I do all that and on Sunday all 8 rivets in the boss parted company with the flywheel !! Lol
Stator lasted 8 years.

[eden]

Yep I do all that and on Sunday all 8 rivets in the boss parted company with the flywheel !! Lol
Stator lasted 8 years.

That's why I had to put a new one on last weekend because my 16 year old faithful one had come loose on its rivets

[coaster]

.................... The pickup consists of 2 coils connected in series and each coil has a resistor across it. When you connect a meter, all you are doing is measuring the resistance of the resistors.

Small correction to the above, each of the coils in the pickup has a DIODE connected across it, thanks for the correction Muppet

[EddieStone]

Update on this. Nothing had failed. The very helpful supplier talked me through adjusting the pickup height, and it's running again.

I think it's got a blocked jet now because it ticks over fine but won't rev unless I put the choke on. Bloody thing. It's very good at getting me to work, but god help me if I want to go anywhere else!

[HxPaul]

Update on this. Nothing had failed. The very helpful supplier talked me through adjusting the pickup height, and it's running again.

If thats the case,why did it run ok when you first fit it ?

[EddieStone]

Well, I was advised that it was probably borderline, and as things settled down (a few heat cycles), or even as it got hot, it moved out of tolerance. The pickup was definitely out of alignment as I could see it after marking the pickup accordingly.

[Adam_Winstone]

When the pickup alignment is out it frequently manifests itself as a bike that will fire and run but with a misfires at certain rev range, often acting as a rev limiter. Why this is more obvious at certain revs, rather than constant across the entire RPM range, is beyond me.

Adam

[EddieStone]

Magnetic fields - it's all witchcraft and wizardry.

Can I sand down the back of the pick up to make it sit lower if need be?