Broken bolt removal, front mudguard > fork bolt

ILMV

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Jesus mary and jospeh, I only wanted to go back and do the job properly (front wheel fitting / copper on brake pads), decided to remove the mud guard for a bit more room, needless to say one of the torx bolts decided to snap, now I have a flush broken bolt, with nothing to grab onto on each side.

Im cautious about wasting 100s of my shity drill bits and messing up the thread, do I have any options for removing this bugger?


Cheers.
 
Buy a cobalt drill from Srewfix direct. They've VERY hard, and should be used at a maximum of 600rpm (ish) but will go through the bolt like Tajine's through me.

Then use an easy-out, or tap the hole and use another screw in it to wind it all the way through...
 
Clamp in vice on milling machine.....Use a 4mm carbide cutter and spiral cut a 5mm pocket to the depth it requires..Remove the threads resembling a spring using a 90 degree scriber....That's just the way I'd do it.

If I didn't have a cnc mill I'd use a centre drill (no wobbly bits) to start the hole and drill it to 5mm.
 
Hi Ben,

Ocean snapped one off on my bike while doing the chain, and they failed to drill it out themselves and had to send the swingarm off to an engineering co to drill out in a jig I presume.

Daves advice sounds good though if you can hold the drill still enough.

Wonder why these bolts snap so easily? makes me reluctant to do any jobs on the bike.

Good luck.
 
Easy outs..

Only trouble I see with easy outs is when the root diameter gets small....ie 5mm...you have to drill 3mm max to avoid deforming the outer threads and then try undoing what's left in the threads with a 2.5mm max root dia easy out.....I stopped bothering to try on small stuff years ago......Easier to just helicoil after drilling oversize......And helicoil is exactly what I do to all my bikes service parts as soon as I get me mitts on em.


Do the original bolts have some form of threadlock on? if so then warm em up before brea...er "undoing" em ;)
 
Cheers guys, this is the bolt that snapped...

bmw_f800gs_mud_guard_bolt.jpeg


It hangs off a little bit but doesn't really go anywhere, so I guess it's not a major problem.

Thanks for the tips guys, I'll get a few drill bits and see what I can come up with, I don't think I can put it in a vice... that would mean taking the forks off and I'm bound to **** something up :D
 
Cheers guys, this is the bolt that snapper...

bmw_f800gs_mud_guard_bolt.jpeg


It hangs off a little bit but doesn't really go anywhere, so I guess it's not a major problem.

Thanks for the tips guys, I'll get a few drill bits and see what I can come up with, I don't think I can put it in a vice... that would mean taking the forks off and I'm bound to **** something up :D

Can you not drill from the rear side which will then encourage the bolt to unwind in the process, wheel off first obviously
 
Cheers Mr Horse, there is actually some exposed thread on the back side of the bolt, do you reckon I could pass another identical bolt through the back and push it through?

Would probably just tighten the situation up a bit more, not sure really.
 
Cheers Mr Horse, there is actually some exposed thread on the back side of the bolt, do you reckon I could pass another identical bolt through the back and push it through?

Would probably just tighten the situation up a bit more, not sure really.

Just drill it through and if it doesn't budge you will at least have a hole for an easy out to get a good grip. Worked for me getting a rear disc stud out.
Make sure you use a new, quality drill bit.
 
Dude, if you think you can not do this, whip the leg off and send it up here. I will get it out for you.
FFS, do not break a drill/eazi-out off in the stud and then ask for help, it will be too late for me then.

Timpo.
 
If you are going to go for it, give it a good soaking with Plus Gas, a dose in the evening prior to and on the morning of the day of the job.

Timpo.
 
Would you f***ing believe it... another torx bolt from the same side of the forks has snapped off.

Seemed to be tight so I made sure I wasn't putting any non-central loads through it, the head snapped leaving barely any thread exposed.

This is starting to get real bloody annoying, as I'll now only have one bolt holding the RHS of the front fender on (I zip tied + tapped the previous example, pictures above).

Off to get some copper slip for the remaining bolts, really concerned about the chain tensioner bolt now... if that snapped I really am screwed.
 
Bad luck Ben What are these bolts made of (cheese I know!) My bike was 2.5 years old with 8000 miles on the clock always kept in a garage dried off after a wet ride and sprayed with f365 and yet a bolt shears. I had do some work on my lawnmower the other day over 25 years old never dried or cleaned never sprayed with oily stuff and yet 6 rusty bolts all came undone without any shearing?
 
My 1200RT was the same, Fixings sheared after 8 months old,:mad: If I brought another new bike I would strip all the fixings out that go into alloy around the frame & wheels and grease them up with alumslip before I did many miles on it at all. :thumb2
 
There's a great video on here of a guy in the States who's front mudguard came off. It dropped him instantly at about 40mph. Don't ride the bike without the mudguard being firmly secure!

I've had a few of these snap over the years. If your careful with the drill you should get them out easily.
 
Can't you drill the hole clear and put a longer screw in with a nut of the backside?:nenau
 
@Timpo After the first time this happend I tried using a bolt extractor but that snapped off and filled the hole too!

Probably needed to drill a longer pilot hole with a better drill bit.

@V8 Yeah I saw that video, only one of the two rearward bolts (see above picture) has snapped, and I've zip tied and taped the f*** out of it.
 
Sounds great fun......................not:blast


Most of the fasteners on the newer bikes are cheese, it appears:(
 


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