1978 R80/7

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IanBrown
Posts: 6
Joined: Mon Oct 19, 2020 9:29 am

1978 R80/7

Post by IanBrown »

my bike had an electronic ignition add-on when I bought it. Been sitting in a shed for over 20 years now....
I want to remove my timing chain cover, but can't figure out how to remove the timing advance mechanism. I don't see anything comparable in my manual. The 2 wires from the electronic ignition add-on disappear behind the timing cover where the advanced timing mechanism is.
How do I remove this last bit so I can pull the timing cover? Also, any advice to stick with the electronic ignition, or try to restore the points and rotor? Thanks!
Attachments
slightly different view of timing
slightly different view of timing
added electronic ignition
added electronic ignition
advanced timing with points/ignition rotor removed (completely rusted)
advanced timing with points/ignition rotor removed (completely rusted)

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schrader7032
Posts: 7400
Joined: Fri Oct 27, 2006 3:00 am
Location: San Antonio, TX

Re: 1978 R80/7

Post by schrader7032 »

Welcome to the forum, Ian! Up front, I like the Dyna III...I have one on my /7. Typically, it's a set it and forget it, but it can be fiddly to get set up just right. Finding a replacement points/condenser can be hard.

I guess you've already attacked the advance unit...the weights, etc. You can see the black donut that is attached to the shaft of the advance unit. With the 10mm nut removed that held the advance unit on, that whole thing should just slide right off. If it's fighting you, then there's corrosion around the advance unit nd the nose of the camshaft. You probably need some penetrating fluid. Once the donut and remainder of the advance unit is off, there is a blue plate that fits up against the cover. This has to come off. It's a delicate piece and if you plan to reuse the Dyna, you'll need to be careful with it.

You might want to read through Brook's page here...he refurbished all this stuff for a R100RS build:

https://brook.reams.me/bmw-motorcycle-r ... -unit-atu/
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

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srankin
Posts: 168
Joined: Fri Jul 14, 2017 8:45 pm
Location: Spencerport, NY USA

Re: 1978 R80/7

Post by srankin »

Kurt hits the nail on the head, corrosion is causing your trouble. Soak the heck out of it with penetrating oil or release type oil.

As for switching back to points, I myself would not. As Kurt says, the Boyer system as you have now is fiddly to set up but once done, it is pretty much fool proof. I have one on my 78RS and have never once since it was installed have had to adjust or mess with it. Unlike my 77 R75/7 with points that had to be adjusted and messed with almost every 10k miles. The worst part about the points on the R75 was when they started to get out of adjustment (always far from home) the bike would start to ping badly.

Forgive me, I am not sure if Boyer systems are still in manufacture or not. I would imagine if the corrosion you have with the system has not damaged the unit very much, it can be reused. Only when you get everything apart will you know the whole story.

There is another system now available through Motorrad Electric, It is made by the Alpha company. It replaces the points with a Hall effect sensor and all is controlled by an ignition module. The system is a kind of modification of the BMW ignition system which was introduced in the 81 models. The only difference is the point system on your bike requires a different mounting system than what was used by BMW. In 79, BMW put the points in a "bean" can. The 81 bikes replaced the points in the can with the Hall effect sensor. On your bike there is no bean can and the aftermarket system is designed around this fact.

To be honest, if the Alpha system had been in existence back when I got rid of the points on my RS, I would have gone with that system. Mind you I don't have a solid personal reason just my "feel" the Alpha system is more aligned with the newer factory system.

Anyway, you have choices now. Oh yes, if you want to keep points, there is a system which can be installed that removes the voltage in the points and turns them into an ignition trigger only. I believe it is called a point system amplifier or something. By eliminating the current flow through the points and turning them into just a trigger, they tend to last longer wearing mainly on the rubbing point on the advance mechanism. A half way between full electronic ignition and pure points.

Good luck with getting things apart, and I bet Brook's video or notes will help a lot more than my note. Cheers, St.
Owner of a 84, R80RT and 78, R100RS

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sblaylock
Posts: 123
Joined: Thu Jul 22, 2010 1:05 pm
Location: Victoria, BC. Canada

Re: 1978 R80/7

Post by sblaylock »

As another option you could look at Euro Motoelectrics and their Digital Ignition System. Rather than connecting to the camshaft, it installs off the end of the crank, which gives more accurate timing.

I've installed several of these on customer's bikes and they have all been happy. Brook Reams has documented this install as well: https://brook.reams.me/2020/04/22/1983- ... on-system/

The nice thing about this one is if you do have the old points system installed you can keep it as a backup. This wouldn't apply to your install Ian as you're struggling to get the Dyna III removed.

Scott.
Last edited by sblaylock on Thu Nov 05, 2020 12:11 pm, edited 1 time in total.
Scott Blaylock
Stoney Peak BMW Service
Victoria, BC. Canada
BMW Classic and Vintage Motorcycle Service and Restoration
service@stoneypeak.com

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srankin
Posts: 168
Joined: Fri Jul 14, 2017 8:45 pm
Location: Spencerport, NY USA

Re: 1978 R80/7

Post by srankin »

Scott, thanks for adding this, I had forgotten about that system. Brook gives a good write up and pictures about the install.

Ian, how are you making out? any progress? I hope you have it apart and didn't have too much trouble. St.
Owner of a 84, R80RT and 78, R100RS

IanBrown
Posts: 6
Joined: Mon Oct 19, 2020 9:29 am

Re: 1978 R80/7

Post by IanBrown »

wow, thanks for all the detailed advice! I only just tuned in here again. Totally willing to stick with the Dyna ignition if it still works. I'll go over Brook Reams stuff first, will let you know how it turns out.

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