Ignition switch bolts loose...

[bbmiller]

Last ride I took on my '91 K1, I noticed that the unit containing the ignition switch had started to vibrate loose. One of the two bolts holding it to the upper fork clamp had actually rattled out and luckily nestled itself against the handlebar. I put the bolts back in as best I could and wired the unit in place so I wouldn't lose it. Now that I'm back home I'd like to square everything away, but these aren't regular bolts. They have a conical head (presumably to be tamper-resistant) and I'm not sure how to get them tight again. Is there any way to get this done at home, or do I need to take it to someone with a Special Tool?

Thanks for the help! I can post pictures if my description isn't clear.

[98lee]

BMW just lists them as 8mm Fillister Head Screws. I would have thought them to be phillips or allen drive. Show closeup pictures.


:dance :dance :dance

[lostboy]

There was a recall on these bolts, but yours are the first ones I've ever heard of that actually backed out. The stock ones are a "one-way" bolt, to discourage theft or tampering. They are readily available from BMW, but you need a special tool (that doesn't work very well) to install them. I prefer to use a normal socket-head bolt. They are 8X1.25-I don't remember the length.

[98lee]

30mm


:dance :dance :dance

[bbmiller]

Sounds like replacing them with something more conventional is the way to go. Thanks for the advice! Here's a photo, just for reference.

[PHMarvin]

Mine loosened on my way to the Blitz to Branson in 2001. After getting back home, I cut a slot on the heads with a Dremel tool. After that, I put a drop of Loctite on the threads and tightened them with a big screwdriver. They never again came loose.

[98lee]

Those appear to be single use security bolts where the drive part breaks off when properly tightened. Problem is, if they ever loosen like yours did, there is no way to re tighten. They probably used those so no one could take those screws out to get to the back of your ignition switch. All other K bikes just use regular allen drive bolts but, they are not K1s.


:dance :dance :dance

[ptero]

My 93 KLT had those and they loosened up over time. I replaced them with allen head bolts. I was guessing no one is going after the ignition on a high miles Kbike, so no worries.