MOTOBRICK.COM

TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: Thorfinn on August 18, 2013, 06:53:25 PM

Title: k75 Ignition switch - is this a Known Problem?
Post by: Thorfinn on August 18, 2013, 06:53:25 PM

Gentlemen,

My recently acquired K75rt appears to have a dodgy ignition switch. Unpredictable cutting-out or no-start episodes, then it's fine for ages.

Is this a known problem? And if so, how fixable  is it?

Kind regards, Thorfinn. :euro

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Scott_ on August 18, 2013, 07:26:46 PM

I won't say that it's specific to the K75, or just BMW.
I think that anything electrical that is exposed(outside) to the weather will eventually have corrosion, contact issues.
If it is specifically "sealed weatherproof" then it's less likely to be subject to problems.
Another large variable to the issue is your location to moisture, eg on an ocean coast with "salt" sea water humidity, or to the other extreme of a arid, hot, dry part of a country. Bikes(and even cars, trucks for that mater) near coastal areas have more problems that ones that are further inland, or that aren't in a "snow belt" area that uses road salt.

You may be able to take the assy apart and clean it up with some contact cleaner and be in much better shape.

One thing that can be a BMW issue is broken ign switch wires in the headstock harness. All of the flexing from turning the bars often has had a history of breaking the wires to the ign switch.

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: pallum on August 18, 2013, 09:17:22 PM

Totally fixable. If the contacts inside are dirty (likely) then all you have to do is clean it. If you have a broken wire or bad connector just replace the connector (4pin trailer connectors from Walmart are an easy buy) or reattach the wires, cleaning worked for me  :)

http://www.eilenberger.net/K75S/IgnitionSwitch/ (http://www.eilenberger.net/K75S/IgnitionSwitch/)

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Thorfinn on August 19, 2013, 04:47:24 PM

Thanks, chaps, for your help and advice. This looks like a useful winter workshop job, one of several! :yes

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: WayneDW on August 19, 2013, 04:51:01 PM

While you're at it, take the starter apart and clean it up as well.

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Thorfinn on August 20, 2013, 04:53:46 PM

Thank you Wayne, that sounds jolly sensible. I'll be doing that this winter then!  :euro

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Grim on August 20, 2013, 05:19:04 PM

Cutting out while running? Cranking but not starting?
That could also be a side stand switch.

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Scott_ on August 20, 2013, 11:45:32 PM

Quote from: Grim on August 20, 2013, 05:19:04 PM

Cutting out while running? Cranking but not starting?
That could also be a side stand switch.

It's my understanding that the 75's don't have side stand switches.

Title: Re: k75 Ignition switch - is this a Known Problem?
Post by: Rickman on September 02, 2013, 08:28:31 PM

I had the same problem with mine, it sat for years so I figured the contacts were dirty. I sprayed a shot of contact cleaner in the key slot and turned the key of and on a dozen times and have'nt had a problem since.