A10 magneto HT pickups

[redmelons]

The front HT pickup on my A10 magneto is fairly stationary when pushed and pulled, but the rearmost pickup rotates several degrees across the bike. Should both pickups be fixed?

[Billybream]

The spring clip secures the pick up brush holder to the magneto and when positioned correctly there will be little movement, but positioning them is a bit of a challenge due to limited access and fat arthritic fingers, well mine are.

[redmelons]

The spring clip secures the pick up brush holder to the magneto

Thanks, I've checked the spring clips and that one is very loose and won't hold the pickup. It shouldn't affect the spark if the pickup rotates though should it?

[limeyrob]

They come in two varieties, a square one that only sits vertically or horizontally and a hex on (looks like that's what you have) that allows more options.  They get worn and don't sit so well and also the gaskets get worn too.  If one flat is out of shape you can swap front to back so it is located on a less worn face.

[JulianS]

The hex based pickups take the HT leads out at an angle to avoid the drip tray and are cranked to avoid the manual advance cable bulge on the mag end cover. They also fit the automatic advance mags. Not handed. First photo.

The pickups for the auto advance take the HT cable out at an angle to avoid the drip tray. They are handed and not cranked so dont fit the manual mag. Second photo.

The pickups which point straight up are not really intended for BSA because the HT cable may touch the drip tray. They are handed, third photo.

[limeyrob]

Good point, I forgot about the 45 deg one

[groily]

As Julian says and illustrates. The different types and part numbers are shown in the Lucas parts lists, and versions were fitted to K2Fs per the specific application as set out in Lucas' Equipment Specification by machine.
It's the cylinder side one that's the pain with a manual mag on As, as it really does need the crank. Uncranked 45° angled handed ones simply will not go on that side.
If a pick-up is too loosely retained by the clip, there's a risk of brush damage and / or of water ingress, but they'll all rotate a little bit if  pulled and pushed. Shouldn't really 'rock' though. (This excludes the 2 screw ones used on late K2Fs and on Comp versions.)
If there's a genuine concern, I'd check the gasket is present and of a proper thickness, and that the clip is undamaged with intact blades and that the pillar is screwed fully home. I've never been averse to a smear of Wellseal or equivalent myself, to help with sealing and with staying put.

[Swarfcut]

 Looks as if the pick up gasket is missing, at least on the barrel side. The gasket positions the tip of the brush holder very close to the slip ring, without it (and with a brand new slip ring) the two parts will touch if you are unlucky. A gasket will also increase the spring blade tension on the pick up. Spring blade has a dimple or did have one originally, to click into a matching dip on the brush holder.

 Somewhere on the forum is a picture of what lies within the pick up moulding, it's pretty clever. I always considered the hex variant to be an aftermarket universal (un-handed) fitment, not a LUCAS part. Just shows my ignorance. Julian's pictures feature the edge of a gasket and the spring dimple locating dip.

 Swarfy.

[JulianS]

This is the inside of a hex pickup, an original old Lucas, dont know what the new lucas is like.