R80 points and electronic ignition

sj_4x4

Member
UKGSer Subscriber
Joined
Dec 15, 2020
Messages
77
Reaction score
7
Location
Cornwall
My 81 G/S has been fitted with a Sparkrite SX4000, it appears to use the points as a low voltage switch to trigger the "electronic ignition".

Who ever fitted it removed the mechanical advance/retard mechanism so all I have in the bean can is the points, to my way of thinking this type of system still requires some form of ignition advance and retard, can anyone confirm or deny this please ?

Also I am looking to set the static ignition timing, I guess fully retarded, which of the timing marks on the flywheel should I be using ?

I don't plan to keep this setup long term, so the big question is revert to OEM setup, tho my bike has been converted to twin spark heads, or a more modern full electronic ignition and if so what would people recommend ?
 
advance /retard is probably done in the electronics . the points do the switching with very low current , so wear on the points face will be vvv low.
 
An 81 g/s should have full electronic ignition.
Seems a bit odd that someone would fit a “ points” bean can.
It’s not exactly an upgrade by any stretch.🤭
Maybe a previous owner couldn’t stop it pinking with the twin plug set up?
 
An 81 g/s should have full electronic ignition.
Seems a bit odd that someone would fit a “ points” bean can.
It’s not exactly an upgrade by any stretch.🤭
Maybe a previous owner couldn’t stop it pinking with the twin plug set up?
Build date is Feb 81, so possibly one of the last with points ?

I had to open up the Sparkrite to try and identify what is was, I am no electronics engineer but it's not made to the highest standards and from what I have read about them I'm surprised it still works, still looking for a recommendation on what to replace it with if anyone has a suggestion.
 
Build date is Feb 81, so possibly one of the last with points ?

I had to open up the Sparkrite to try and identify what is was, I am no electronics engineer but it's not made to the highest standards and from what I have read about them I'm surprised it still works, still looking for a recommendation on what to replace it with if anyone has a suggestion.
Only bikes that had points in bean can were 1979.
Prior to that the bikes were heavy flywheel with conventional points driven off the end of the cam.
Post 79 bikes had electronic ign.
Points in bean can were only fitted for 79.
And afaik never used on a g/s
 
For the electonics to
Only bikes that had points in bean can were 1979.
Prior to that the bikes were heavy flywheel with conventional points driven off the end of the cam.
Post 79 bikes had electronic ign.
Points in bean can were only fitted for 79.
And afaik never used on a g/s
Thanks for the response, I am just finishing off replacing the ST clocks and generic headlamp someone had fitted with the correct setup and Acewell speedo, so BMW budget needs topping up again before fitting a Wedgetail.

My engine number returns a build date of Feb 81 but it clearly has points in the bean can, so I guess in the 45 years it has undergone a lot of changes.

I do suspect front end damage at some point as that would explain it having the wrong clocks, headlamp and incorrect mud guard, perhaps the front of the engine also took a knock, the plan is to get her at least looking like she should, with a few modern upgrades.
 

Attachments

  • 20250126_151124.jpg
    20250126_151124.jpg
    150.1 KB · Views: 33
Pictures as you go along with the changes……we all like to see pictures.

And I echo the above comments…fit a wedgetail.
 
I didn't take many photos, but here is the bike as I brought it with all the wrong bits on the front.

As Purchased.jpg

With the headlamp removed, plastic spacers allowed water ingress so surface rust on the chrome, quick fix was some rubber gaiters, future me can worry about a re-chrome in the future.


EarsHidingRust.jpg

It's had a new loom at some point, but a fair bit of bodgery to get ST clocks working.

Making ST gauges work.jpg20241215_152332.jpg

The Sparkrite, had to find out what it was by googling the number on the PCB

20250121_162015.jpg

Eventually found the most expensive bit of bent tin on the planet, and got bent over again on customs charges to rub salt into the wound.

Howmuch.jpg

Fully assembled using the surround purchased from Nin a few years go, it had loads of holes in it that someone had made with a rusty spoon so they could fit a screen, all filled and sprayed.

After1.JPG

Had to fill and spray the tell as well, but all fitted with the Acewell and seems to work, will test ride at the weekend.

After2.JPG

Anyone got a correct front mud guard ?
 


Back
Top Bottom