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

Hi all, thanks for your tips re the hall sensor. After swapping a few wires as suggested, I determined the Hall sensor was cactus, so I bit the bullet and bought a "made in Germany" after market replacement. Fitted that, gave it some fresh fuel and it fired up nicely. 

However, after a minute or so, it started spewing out white smoke. I assumed this was a bit of residual oil on, and perhaps in, the exhaust, so just switched it off and decided to burn it off after I got it out of the shed. Well, today, I got it out of the shed to give it a decent run (parked in the driveway) to burn off the gunk, but that didn't happen. Basically, it fired up OK and the exhaust gas was fine and clear, until it warmed up. The warmer it got, the more smoke came out and it just kept getting worse. This is not just a bit of residual oil. I also noticed some condensation on the inside of the oil sight glass. I turned it off, but now it has cooled down, I can't see much evidence of water/coolant in the oil sight glass. The oil looks its normal honey colour (recent oil change). The sight glass is also new, so you get a good view.

Any thoughts? I was fearing the worst (head gasket, etc), but was wondering if maybe there is oil/coolant mixing in the oil/water pump? At least that might be an easier fix.  Would that cause smoke in the exhaust? Maybe it's something else altogether. 

Any help/guidance appreciated.

thanks

TacKler wrote: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

Ive fitted them....some 100,000 klms ago

All good

Robdog wrote:Any thoughts? I was fearing the worst (head gasket, etc), but was wondering if maybe there is oil/coolant mixing in the oil/water pump? At least that might be an easier fix.  Would that cause smoke in the exhaust? Maybe it's something else altogether. 

Usually it is oil going into the coolant system after failure of one of the seals in the water pump and not the other way round.  Best way to check this is via the coolant tank on the RHS.  Pop the lid off and look for a milky mixture or blobs* of it which will necessitate the removal of the water/oil pump and replacement of all the seals.  

If the moto sits on the side stand for a while instead of the centre stand then a smoky exhaust can occur and varies from moto to moto.  That can be from a few seconds to a complete fumigation of your shed.  It is to do with oil weeping past the piston rings into the exhaust manifold whilst on the side stand.  If the bike is going to stand for a while it's best to hoick it onto the centre stand.  

Both of these problems have been covered here multiple times.  

You don't really hear about head gaskets going on these engines but you never know the history of what you are getting.  

It probably would not hurt to keep a complete water/oil pump seal kit on hand and red gasket goop for future use.  I've done a few and keep a seal kit on hand.  



* a technical term for which the proper name escapes me at the moment.

Welcome aboard, even if you are a cockroach.

Maybe they will have a better team next year (but I doubt it).

Cheers,

Andrew

Thanks Pegasus. I doubt it too.

TacKler, we’re talking about a complete shed fumigation. The bike was running fine a few months ago and just died as I was backing it out of the shed. After fitting the new hall sensors, it fired up again nicely with no exhaust gases, but then started spewing smoke after a couple of minutes as it warmed up. It had been on the centre stand the whole time. 
I can’t see how just sitting in the shed not running would damage the head or gasket, so I’m hoping it is the oil/water pump seals. I can’t see any oil in the coolant.
The only similar thing I’ve seen was on my old (1993) petrol Toyota Hilux. It had water in the oil and visa versa. After removing the head, we found no problems. Turned out to be the timing chain and tensioners were so loose, the chain rubbed a hole in the side of the (adjacent) water pump housing allowing oil and water to mix, but I don’t think this is even a possibility on the K bikes. Also, it didn’t generate the same white smoke.

Hi team and apologies for not updating this.  After letting it sit over winter, then a little (actually a big) trip overseas, I decided the bike was running too well to be a significant issue. So I bit the bullet, wheeled it out into the open (so it wouldn’t burn the shed down), fired it up and just let it run. About 10 to 15 minutes later, the smoke cleared and we were good to go. I had no idea so much oil and petrol could build up in the exhaust. Anyway. All good now. She’s going like a rocket, again. 
Now to fix a few of those niggling little issues:- I’ve

• replaced the “comfort” seat with a good 2nd hand RS seat;
  
• Replaced the throttle grip and cam with one that has all it’s teeth;
  
• Replaced the “lunchbox” attachment bolts after a PO did a dodgy repair.
  

Still to do:-

• Check the timing after replacing the Hall sensor;
  
• Replace the odometer gears;
  
• Replace the gear selector switch at the back of the gear box (a previous “fix” means neutral light is alway on);
  
• Replace the gear indicator LCD screen (if I can find one in Oz).
  

Many thanks to Graeme from Kmodel Beemer bits in Bega for sorting me out with a range of 2nd had parts.

FYI: The smoke is caused by oil seeping past the piston rings, especially if the bike is parked on the side stand. You can mitigate this if you turn the bike off and then tilt it to the right for a few seconds before putting it on the side stand. This lets the hot oil behind the pistons drain into the oil sump so there's less oil left to seep past the rings.

Cheers Duck. Good advice.

You don't say if you replaced the HES as individual items onto an existing plate (done that multiple times and so have a couple of the Aussies) or replaced the entire plate with another OEM, so two comments:

- if you replaced just the sensors and they sit in the same holes
- you replaced the plate in the same position that it came out

then you shouldn't need to worry about the timing. There's a cutout on the side of the plate that lines up with a cutout in the engine block - that's it, timing done.

Dai, I replaced the plate in the same position the old one came out of and lined it up with the cut out. I was pretty careful with the alignment. The Haynes service manual says “it is essential that the timing is checked properly as soon as possible after the ignition trigger is disturbed”. So that was my plan. As you say, it should be OK. It is certainly running well.

Welcome Robdog, Using a timing light is difficult and not very precise on our bikes. You can try but with the front wheel removed so you can look straight into the cut out. 

You can try advancing the timing about 6º until the engine pings on acceleration then back it off a tad. It takes trial and error to find the sweet spot and the movement is minute ever time.

Use the search function on the Portal page to find some threads on it.

Enjoy the forum

Cheers 88.