I have been having an intermittent no start condition on my K100.  I discovered if I wiggled the wiring harness going to the fuel injectors it will start and run fine.  Soooo, I already inspected the externals of the harness and it looks fine with no breaks or open spots.  So I suspect its at a connection.  This harness combines with another harness and goes to the ECU? unit.  So I want to check the connection there.  It seems to be secure and has a screw holding connection in place.  I want to disconnect this connection and inspect.  Are there any precautions I should take other than disconnecting battery?  I dont want to inadvertently damage something and I know the electrical components can be tricky.  Thanks

Which year K100? If it's 83-86 wiggling the loom is almost certainly moving the fuel tank connector which is a known no-start problem. Pull it out, close up the female pins in the plug using a very small screwdriver and try again.

Now that you've been a member for a little while, go up to Profile and then Signature and type in your year and specific model so the members know what bike you're attempting to fix. Models vary widely as far as fuel injection - Motronic or L Jetronic - and K100 models can be 8 valve (early) and 16 valve (later), with some overlap.

Dai wrote:Which year K100? If it's 83-86 wiggling the loom is almost certainly moving the fuel tank connector which is a known no-start problem. Pull it out, close up the female pins in the plug using a very small screwdriver and try again.

Yes, its a 1985 BMW KRT100.  Hmmm.  I see the harness that goes to the injectors is connected to another harness that goes under the tank.  I presume that is the one you are talking about.  Looks like I will have to take the fuel tank off to get at connectors, right?

Two Wheels Better wrote:Now that you've been a member for a little while, go up to Profile and then Signature and type in your year and specific model so the members know what bike you're attempting to fix. Models vary widely as far as fuel injection - Motronic or L Jetronic - and K100 models can be 8 valve (early) and 16 valve (later), with some overlap.

I just looked at my profile and included that its a 1985 BMW K100 RT.  thanks

Go to your Profile, click on the Signature tab and put it there, too; done that way it will show up in every post you make.

If your gas tank is bolted down at the rear, the electrical connector at the front left is a very well known weak point.

You can adjust the pins a little so you get a good tight mechancail and therefore electrical connection. I bought a few rebuild kits for those connectors from www.tills.de as 3 of my Ks have those early connectors.

92KK 84WW Olaf wrote:If your gas tank is bolted down at the rear, the electrical connector at the front left is a very well known weak point.

You can adjust the pins a little so you get a good tight mechancail and therefore electrical connection. I bought a few rebuild kits for those connectors from www.tills.de as 3 of my Ks have those early connectors.

I cant find those kits you mentioned.  Do they still sell them?

https://www.ebay.co.uk/itm/132968760102

He's a (very good) UK seller but the pictures might help you turn up the same connector on ebay.com. Pity he doesn't name the manufacturer. Try searching just '4 way connector' under catagory 'Cars, motorcycles & vehicles'.

The connector just unplugs from the left side of the tank. Just pull straight down.