OK, I've calmed down now
 

Apologies if I offended anyone with my earlier rant but I was really upset. The bikes been off the road for 2 weeks and I've been training it. Today should have been D-Day but now I have to remove the remains of a sheared bolt from the engine casing and wait for my dealer to get a replacement bolt.

Anyone know of any tried and tested way of removing this without damaging the thread? If anyone has an inspection mirror can they look behind to see if it's an open hole?

I'm off down to Halford's in 15 mins to see what they have. It'd be nice if I could ask for the correct tools by name.

http://www.curium.org.uk/images/misc/nuts.jpg

It's an open hole, you should able to reach behind and unscrew the bit of the bolt that's still there, you shouldn't need to go to the trouble of a screw extractor, unless it sheared because it was cross threaded for example.

Do be careful whatever you do, the stub that it's in is part of the generator case, don't lean on it, you risk breaking the case.

So far everyone I've spoke to said not to use a stud extractor as they're are rubbish and prone to snapping.

Getting hold of the bit of bolt protruding from the other side will be difficult (impossible?) as there isn't much clearance for getting any pliers in from behind.

This leaves me with drilling. I've no experience with this at all but basically from reading around I would dot punch the shank of the bolt and then starting off with a small drill bit, drill progressively bigger holes until there's not much bolt left. I may then have to clean up the thread before fitting the new bolt.

Other suggestions are welcome.

As Ian (Sid) says, that lug is pretty delicate. I'd advise against hitting it with anything (e.g. centre punch) 'cos a sheared bolt will pale into insignificance when you're sitting looking at a snapped off lug in your hand.

If you take the clutch mechanism off it should give reasonable access.

It's sometimes possible to use mole grips to clamp the bolt end-to-end if it protrudes enough, and turn it that way. Maybe a small spacer if the bolt end is recessed in the hole. Just a possible :?

Try warming it with a hair drier or hot air gun, and adding WD40 or similar. The alum should expand a bit and might help ease it.

Screw extractors are indeed tricky things to use successfully.

If all else fails I suspect you could drill it out and use a nut and bolt (if there's room, tricky to assemble but possible), or ideally helicoil it, but just don't break it off! :shock:

Fished about a bit more and decided on a strategy.

I'll take the mechanism off and see if i can get a grip from behind to turn it out. I know its not corroded in so with a good purchase it should come.

Plan B.

I've purchased some liquid weld and a twist gimlet. I'll drill into the shank and then weld the gimlet into the hole, leave that for a couple of hours and then attempt to twist it out.

Hows that sound?

If that weld stuff holds up all well and good - I understand why most people would say not to use an extractor, but that's 'cos most people only know about tapered extractors, I never use a taper extractors - but if needs, be a parallel side extractor would work.

All else fails and you do brake the lug off, I think I've got a spare kicking around.

O, and you really don't have to get the bolt from a dealer :!:

Cheers Mark

I hate having to get bolts from dealers but there is nowhere i know off where i can walk in and pick up a matching bolt preferably in stainless steel.

You'll get standard zinc plated M6 bolts/setscrews from any car accessory shop if you're really stuck. That's not exactly a heavy duty application, and it's behind a cover anyway, so any type should do the job.

you jest surely :shock: ever hear of halfords? B&Q?

all else fails rob one from a non critical part of the bike for now.

Cheers Mark.