Hi, and greetings from Australia on a coolish May afternoon. While it’s usually warm in Oz, I live in the mountains west of Sydney (hills by most other countries’ standards) at an altitude of just under 900m. We’ve already had a smattering of snow this Autumn. I’ve been a member for a while, been following posts for a couple of years and thought I’d better (finally) introduce myself. I’m the proud owner of a 1984 K100RS that I bought as a non-running project a couple of years ago. My aim was a renovation back to original, not a full restoration, and not a cafe. Well, I eventually got it running by replacing the injectors and fuel rail (rusted after sitting for a number of years), the fuel pump, filter and all the fuel lines; all the fluids, plugs, battery and the usual consumables. The bike had no working brakes at either end, so I overhauled them and replaced the lines with braided lines made locally. Unfortunately, the rear master cylinder and rotor had to be replaced. Most of the electrics were salvageable and, after much fiddling and cursing, managed to get the old girl running and registered on Club plates. I’ve had a few runs, mostly local, til I build trust in her. Currently she’s sitting in the shed not running again. I suspect the Hall sensor, as there is no spark on cyl 2 or 3, even after swapping the two coils. Anyway, I’m sure there is a lot more entertainment and enriching of parts suppliers to come.
Thanks for having me and apologies for the delayed intro.

Welcome to the forum.  
It very easy to test the Hal sensors. The circuit to make the simple test light is in the tech pages 

Jaycar also sell the sensors in Australia.

Cheers Matthew. I’m just thumbing through that now. I’m a bit nervous about self testing given the “warning” in bold red letters in that section of Frog’s excellent post. I wasn’t aware Jaycar sold Hal sensors to suit. The BMW ones are pricie.  I’ll check it out.
Suspect it’s a bit warmer where you are.
Thanks for your help.

Matthew, this is the closest one I could find on the Jaycar web site, but it doesn’t look like a match. Don’t suppose you have a link?
[url=https://www.jaycar.com.au/hkz-101-hall-effect-device-re-introduced/p/ZD1900?pos=3&queryId=a99fe70fbc76d145fd9bc4020623bb41&sort=relevance&searchText=Hall effect sensor BMW k100]https://www.jaycar.com.au/hkz-101-hall-effect-device-re-introduced/p/ZD1900?pos=3&queryId=a99fe70fbc76d145fd9bc4020623bb41&sort=relevance&searchText=Hall%20effect%20sensor%20BMW%20k100[/url]

These are the ones I purchased from Jaycar.  Have not had a need to fit them yet.  

https://www.jaycar.com.au/hkz-101-hall-effect-device-re-introduced/p/ZD1900?pos=4&queryId=e6ca425d3650ddfe024270f2175c725d

Cheers TacKler.

Welkome Robdog, from just up north of you in the Hunter Valley. Keep an eye out for get togethers if you would like to meet some of us in person as you will be most welkome.

The southern Queensland crowd and NSW Krew get about fairly regularly and there's plenty of good company around the bar/fireplace on those occasions.

Cheers

Thanks for the welcome Gaz. North is definitely the direction to head at this time of year.

Welcome from the Northern K Kronies.
Regards Martin.

Welcome Robdog. 

Something else to check is to see if power is supplied to the positive side of the primary circuit to the 2-3 coil. If it's not getting power the hall sensors are probably good.

A quick way to test the hall sensors is with a computer safe 12 Volt LED test light, which you can probably get at your local hardware store for about $10, and can also be used to check the primary side of the coils.

Cheers daveyson. I hadn’t considered that. Will have a look. Ta.

Thanks also Martin and the northern K Kronies. Hope to catch up when my K is humming along nicely.

If swapping the black/red and black/blue wires (from the ICU to the coils) results in no spark at cylinders 1and 4, that wouldn't be looking very good for the Hall sensors.

Gday Robdog

Robdog wrote:Matthew, this is the closest one I could find on the Jaycar web site, but it doesn’t look like a match. Don’t suppose you have a link?
[url=https://www.jaycar.com.au/hkz-101-hall-effect-device-re-introduced/p/ZD1900?pos=3&queryId=a99fe70fbc76d145fd9bc4020623bb41&sort=relevance&searchText=Hall effect sensor BMW k100]https://www.jaycar.com.au/hkz-101-hall-effect-device-re-introduced/p/ZD1900?pos=3&queryId=a99fe70fbc76d145fd9bc4020623bb41&sort=relevance&searchText=Hall%20effect%20sensor%20BMW%20k100[/url]

Sorry Robdog could not get your link to work

But the ones in Tackler post are the same ones I used to fix Koos k75 

I carry a fully tested plate in my spares within the rear ducktail of the seat as this has been one of the things that has cause a bike to breakdown on a ride

Thanks all for the warm welcome, although I feel like a bit of an imposter as I’ve been stalking the site for a couple of years.

Matthew, the link I posted took me to the same place as yours, so all good. Carrying a spare plate sounds like good advice.

Now there’s just the “doing”.

Howdy!

Hi,

to this forum!


Bernie

Thanks Fishboy, Bernie and Bad Boy