Does anyone know about helicoils and thread inserts etc?

Draeger

Draeger

Draeger

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Got myself a new carbon fiber rear hugger for the RSV ages ago and only got around to attempting fitting now.

Yesterday, I tried to remove the old carbon hugger.

The bolts were absolutely rock solid.

So I applied some WD-40 and left it to sit for a while, then tried again.

Still no joy. Impatience got the better of me and I ended up trying brute force.

Result was, first one, the head of the bolt sheared off. :eek:

Moved on to the next one and it felt like it eventually had started turning. But no.....it was twisting unbeknown to me and it too sheared off.

Eventually got the last two off without them shearing.

So my question is, how on earth do I repair this?.

There's no way the two that snapped can be gripped ( whats left sticking out of the swinging arm ) by any means so I guess I am looking at drilling them out.

Once I have done that what do I do?. Been looking on Google for answers and it would appear some sort of thread repair kit and inserts/helicoils are required?.

Trouble is, I've never used this sort of stuff before and I have no idea what the procedure is.

The size of the original bolts were M5x12.

What does the "12" bit mean?.

Having read through some posts via a Google search, it would seem I need to drill out the remains of the old bolt, do something with an M6 and insert an M5.

All totally confusing!!!! :confused:

Hope someone here can point me in the right direction. :)
 
An M5x12 bolt the 12 denotes the bolt length iirc..
An M5 thread has a thread pitch of 0.8mm

You dont want to run a Standard M6 tap down the hole after youve drilled it out, You will need a specific M5-STI tap and M5 Wire STI (STI is Screw Thread Insert) which is what old folk like me still call Helicoils, some stores refer to them as STIs also.

If youre careful thoug, when drilling out the broken piece, using a 3mm drill bit you may be able to drill out the old bolt, and the force and heat may dislodge it and not damage the existing thread.

Im not sure where you will be able to buy the Tap and tap wrench from though sorry, id borrow them from work if i needed them myself.

Everything you need but expensive.
 
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You can get these things which have a pointed end and an opposite thread, so when you do it up into a hole you have drilled into the bolt, it will get tighter and eventually lock in, allowing you to undo it.

They're called easyouts.
 
Darryn said:
If youre careful thoug, when drilling out the broken piece, using a 3mm drill bit you may be able to drill out the old bolt, and the force and heat may dislodge it and not damage the existing thread.
Click to expand...

This is what happened to me on a few fairing bolts, drilled them out and the force and vibrations unstuck the rest and once the head was off the rest I could easily screw out with my hand.
 
Cheers for the replies folks.

Only thing is about using an extractor and drilling the pilot hole is that these bolts are absolutely tiny stainless steel M5 ones, into an alloy swing arm.

I suspect drilling something that small will be tricky and access is awful. :(
 
georges said:
You can get these things which have a pointed end and an opposite thread, so when you do it up into a hole you have drilled into the bolt, it will get tighter and eventually lock in, allowing you to undo it.

They're called easyouts.
Click to expand...

Which are designed to snap off in the broken bolt/stud and make removal almost impossible. Easyouts are also not really suitable for anything as small as an M5 bolt.

The answer is that the remains of the bolt will need to be drilled out. If there is any of the bolt standing proud of the surface, file it down flat and centre punch it as accurately as possible in the middle. Start with a small drill, say 3mm and drill down the middle of the bolt. Step up the drill sizes in 0.5 mm increments. If you drilled the first hole accurately, you should be able to drill out most of the old bolt without damaging the original threads. You can then very often pick out the remains of the original bolt with the end of a scriber etc. If this doesn't work out then one possibility is to drill through with a 5mm drill and tap to M6, as long as the hugger can take an M6 bolt head. If not then it's time to look at thread inserts such as helicoils.
 
Cheers Dogbreath, will try that.

I'm going to have to borrow a Dremel with a flexi attachment methinks, otherwise I will end up having to remove all the rear plastics, the undertray, the exhaust end can and the subframe in order to get a straight run from above with the drill. I don't relish the prospect of that again ( been there before :rolleyes: ).

So if I end up having to drill out to 5mm and tap using an M6 what exactly am I looking for?.

Just Google "M6 tap" or something so I know what I need to buy?. :confused:
 
I love drilling & tapping but then i am sad like that.
Basically you just drill a hole insert a bit then undo it it in reverse. Helicoils are different as they replace a thread rather than extract a bolt/stud.

Hire or buy a drill & tap set by the sounds of it you'll need it in the future anyways :p
 
I'd be inclined to say remove the rear subframe and do it that way with clear access as this really isn't the sort of thing you want to be doing with limited space and no clear line of attack.
 
Dureth said:
I'd be inclined to say remove the rear subframe and do it that way with clear access as this really isn't the sort of thing you want to be doing with limited space and no clear line of attack.
Click to expand...

Even with one of those flexi attachment thingies on a high speed Dremel?. :(
 
I didn't read your O.P properly Sorry but the spacings do my head in & make it hard for me to read.
Dureth is right, You need to be straight on with your attack not all flexed up & wonky. I do mine on a bench or if it's on the lump itself the lump will be on the floor or the car that stripped out i can get a dead straight approach, ******* in the wind otherwise.
 
Roger that.

Well - that's my weekend sorted out then.

Stripping the entire back of the bike.

The undertray, battery housing etc on an Aprilia RSV is a complete pain in the proverbial to remove, even worse to refit!!!

Time to get the plasters out for the knuckles. :p
 
Only the wheel & the swinging arm & I'd be temted to just drill it right out seeings it's on a bike & fit some of those trick Allan key headed nice looking ones.




Note to self !!!
Read the ******* O.P. properly you ignorant ****.
 
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