help identify Bosch ZEV armature

[Scooter6]

Good evening,
I have a Bosch ZEV 45 deg parts mag I am wanting to make functional and the armature is missing the collector ring and front bearing. I am wondering if this armature is for sure ZEV before I continue. There are threads in front of the collector ring, but I do not see a nut in the Bosch ZEV parts list and cant find pictures of ZEV armatures that do not have a collector ring on them to know what it looks like.
This armature is marked 45 deg.

I am probably going to make some parts for this to keep its cost down. I do not have an interrupter housing and I know it needs to be made of brass and not sure why those are not aluminum. I do know why the are not iron to not interfere with magnetic field.

I need to replace the points and points base because it is for CCW and I need CW.

I apologize if this topic has been covered, I tried a search and have not found the specific question of armature ID.
Please let me know what you know.
Thank you,
Scooter

Bosch armature 1.jpg

[BoschZEV]

You should find the following thread useful:

https://www.britbike.com/forums/ubbt...mature-magneto

[BoschZEV]

p.s. I have a ready-for-total-restoration Bosch ZEV that's surplus to my anticipated needs. Although I rarely sell anything (because, I never know what I might need), if you need it, make me an offer I can't refuse.

BoschZEV.jpg

[Scooter6]

Good evening,
Thank you for the reply and thank you for offering magneto. At this time I cant bring myself to commit because mine is going on a Excelsior engine that seems to be taking financial precedence. I will probably make parts or move on to the Midco mag that came with the engine. I have not taken it apart yet.
Thank you for the detailed article, I read it the other day, but still did not see picture of the threaded part of the front of armature to see what a nut looks like. Collector rings I have seen do not look like they have a recess for a nut and it looks like the bearing is directly in front of it.
I am wondering about a source for the front bearing? That is something I cant make.
Thank you,
Scooter

[BoschZEV]

Good evening,but still did not see picture of the threaded part of the front of armature to see what a nut looks like.

Sorry, I didn't realize I hadn't posted a photograph on that site of the ZEV armature with the slip ring removed. The shaft under the slip ring is a cylinder, not threaded. The armature you have isn't from a ZEV.

[Scooter6]

Thank you for letting me know about the armature. That just continues to be my luck with project Excelsior engine. Sounds like I need to consider your mag. I will PM you with a couple questions.

Any idea what model this armature is from? I figured it was ZEV since it is marked 45 deg.
Thank you,
Scooter

[Scooter6]

Good evening,
I am wanting to put this magneto on 1920 Excelsior engine. I have parts to build one magneto but I have two types of housing assemblies and magnets. One has two magnets and the other has one magnet.
Does anyone know which would most likely be period correct? I have tried to find 1920 photos of cycles with mag but cant tell.

Also wondering what the pin screw is for in the back cover? Refer to attached image. pin in back of Bosch ZEV.JPG
Is the end play shimmed behind the bearing on the armature. Mine have what I think is too much.
Please let me know.
Thank you,
Scooter

[bernhardt]

Are you asking what mag did it come with originally? 1920 Excelsior came from the factory with a Berling E 21 mag. The Zev can be used if it's the correct rotation and 45 deg.

[Scooter6]

Good morning,
Thank you for letting me know the Excelsior did not use Bosch as option. I do plan to put a Bosch ZEV on and I am wanting to use one that is correct for 1920.
Thank you,
Scooter

[gharper]

Scooter6,

The threaded portion is for the end disc of the collector ring to screw on. The inner piece is warmed up and pushed on, then the end disc is screwed on. There are repops available of the entire collector ring assembly, search BOSCH ZEV COLLECTOR RING. If you clean the armature well, you will see stamped on the outer edge a number, probably 42 or 45. That will be the degree the mag was originally built for. There are also similar stampings on the top of the stationary pole shoes of the mag body. The little pin you circled is the contact for the grounding circuit. When fully retarded, the spring steel contact that goes to the external grounding screw will touch that pin and ground the coil, killing the engine. It is in the 11:00 position, which is for a CW rotating mag. It can be put into the 1:00 position for CCW rotation. 15 and up Excelsior used CW rotating mags, looking at the drive shaft.

Alex is correct, the ZEV was not used on Series 20 X. When the US entered WWI in early 1917, we stopped buying stuff from the Germans! US motorcycle manufacturers had to find an alternative to Bosch mags. Excelsior and Henderson switched to Berling, Indian to Dixie, which later merged with Splitdorf. Harley used Berling as well, but pushed their full electric models with in house components, so mags became an uncommon option pretty early.

You mentioned you have a Midco unit that you would like to resurrect..... For what you're doing I would say stick with the ZEV, parts are plentiful and they're easy to work on. The Midco is a MONSTER to get working! It is a complete electrical unit consisting of a generator armature, fields, 2 high tension coils, 2 condensers, 3 sets of points, fuses switches and a 4/1 step up internal helical gear drive for the generator. The end castings are zinc die castings and distort terribly, causing all kinds of alignment issues. I was able to get one going for my 19 X and it all worked, but it was a bear to get right! You'd do better to sell, or trade that off to someone trying to build up an electric model and concentrate on a simple mag for your project.

[Scooter6]

Good evening,
Thank you for all the helpful information.
When you mention the inner collector ring piece is warmed up, do you mean like a blow dryer would do or heat gun? Do people heat them up to remove them? I am not going to try to remove it if it is a high risk of damaging it or the coil. Coil may be useless anyway, I have not had time to test anything.

I am also wondering if the bearing inner race is heated slightly to remove it? I just tried to remove mine with slight force and it did not budge. I am asking because I have two mags and may need to switch parts to make a good one.

Both are 45 degree. Thank you for telling me about the contact for the external grounding screw. That grounding screw assembly is currently missing from both mags so it was not obvious to me what the pin screw was for.

Regarding the question of year of mag. I bought the ZEV parts mag offered to me and I am making a couple of parts but can build one complete CW 45deg. One mag is early and uses two magnets and the other is late and uses one magnet. I am trying to figure out which design would have been used on motorcycles on or just before 1920. I have tried to find original photos of various 1919 and 1920 bikes to figure it out but have not found a clear enough photo. based one the little Bosch advertisements I can find, I think the single magnet version did not come out until after 1920.

I cant wait to get time to take the Midco apart to learn more about it. May not get it going, but will learn more.

Thank you,
Scooter