Fixing a broken ignition lock after attempted theft

[Pete.]

Just recording this here in case it's useful to someone later if they have their ignition torn out like I did this week.

After someone ripped out the ignition barrel on my bike, I bought a repair it from Motorworks. The kit is a new barrel with a bag full of tumblers that you mix and match to suit your original key. It's held in by a sprung pin that you poke a little wire into a hole to depress when you want to pull the barrel out. Only problem was that in ripping out the the barrel they also broke the top off the little alloy bit that the pin locates in, so my new barrel wouldn't stay in.

bmwign1.jpg (124.52 KiB) Viewed 12020 times

So, not wanting to fork out for a new lock I thought about how to fix this one. The other side of the mechanism has a perfectly sound piece of metal that I could drill for the pin, if only it protruded from the opposite side. There's a handy hole that is supposed to be where you poke a tool into the depress the pin, so I used a 2.5mm drill through that hole to drill another blind hole opposite, the re-ground the end of the drill flat to square off the bottom of the hole.

bmwign2.jpg (73.8 KiB) Viewed 12020 times

bmwign3.jpg (94.55 KiB) Viewed 12020 times

Now for the barrel. The pin direction has to be reversed so I drilled the blind hole right through 2.5mm and tapped it m3 then loctited a m3 screw into the thread just a few turns in.

bmwign4.jpg (129.14 KiB) Viewed 12020 times

bmwign5.jpg (90.15 KiB) Viewed 12020 times

Then cut off the screw, ground it flush and that's it - the plunger now pokes out the other side. I put it all together and it works perfectly.

bmwign6.jpg (110.35 KiB) Viewed 12020 times

Only possible downside is that there is now no way of ever removing the barrel without destroying something, but that's not too bad because it means I would only have to buy a new lock, which the repair has saved me from buying anyway
In hindsight, after drilling the barrel to reverse the pin and making the new blind hole I should have taken a 1.5mm drill and carried on right through to the outside, so that the pin could have been released later. With luck I'll never have to worry about it.

[ianc53]

Thanks for posting this, always impressed when someone uses some skills to avoid paying BMW more money.

Cheers

Ian

[dave the german]

Would it have been possible to use a grub screw? Not sure how the lock looks in situ and whether this would make it easy for a tea leaf

[Pete.]

Yes Dave it would be possible to just use a m3 grub screw and I considered it. You'd have to use a dog point one with a 2.5mm or smaller point. I looked though my tray of grub screws and didn't have one that was M3.

No issue with tea leaves since you'll always need the key to pull the barrel (properly).

[dave the german]

All sound advice from when/if it happens to another Trixter - this forum is invaluable