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Security bit identification and how to get it out

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Rainbows22/07/2018 09:59:22
625 forum posts
178 photos

Fished a bike out of a local pond using a piece of steel tied to a rope but since wheeling it back to my garage to restore it I found some odd ball fastners.

First is some Penta Plus sockets holding the pedals in

The second pair, holding the handle bars and seat on I don't even recognise.

Anyone recognise this bad boy?

Awful quality photos but my camera cant seem to differentiate the different shades of black too well.

Second part of the question is how do I get them out? A penta plus driver would be fairly easy to make if I had a dividing head but alas don't have one of them. Im not even sure how the geometry on the 3 spoke one works. A triwing driver didn't get deep enough in. Thinking off drilling them out but I feel the geometry would chowder up and drill bit. Any ideas?

JasonB22/07/2018 10:04:34
14867 forum posts
1492 photos

Odd to have security fixings on a bike, are you sure it's not a stolen/dumped "Boris bike" or similar?

peak422/07/2018 10:10:58
714 forum posts
65 photos

Could it be a different size TriWing driver? Like these

What make of bike is it?

Not sure what lathe you have, other than a Pultra or similar, but are the bull wheel teeth divisible by 5, in which case a detent on there would do for indexing. If you've a large enough mill, you could even mount a miny lathe, or its headstock, on that and use as a dividing/indexing head.


Edited By peak4 on 22/07/2018 10:29:58

pgk pgk22/07/2018 10:19:15
1229 forum posts
278 photos

If you have a mill then the penta driver should be possible without a dividing head - just some round stock and cut the first flat by calculated depth and then rotate using a simple template of the angle against an engineers square? That should get you the plug shape and I'd reckon a good chance you could anneal and hammer some tube around that for the socket shape.

You mght be able to use a similar technique to make the second driver too with the stock vertical and PCD to plunge-cut the three radii for a template to hammer a socket to shape? If you don't have a cutter the right diameter then fly cut it down or use a boring head.


Vic22/07/2018 10:32:17
1968 forum posts
10 photos
Posted by JasonB on 22/07/2018 10:04:34:

Odd to have security fixings on a bike.

Yes agreed. I suppose cycle shops will have the drivers for these?

It’s bad enough that M7 is a standard cycle thread. smiley

Gordon W22/07/2018 10:56:01
2010 forum posts

I've just acquired a bike- all sorts of threads and heads. I suspect the head types are more for looks than security, as in "wow, it's got security bolts, must be expensive ". Also there are many different makers of the bits and all have their own ideas. Does not solve the problem tho'. I have a couple of assortment packs which do most ,but not the penta-lobe. Will get them when needed.

Ian S C22/07/2018 11:01:07
7224 forum posts
227 photos

The bike makers like selling expensive tools. The first one I'd take the Dremmel, and either cut a screw driver slot across the screw head, or do as I did for Robinson screws and modify an old Philips screw driver(in that case square), it's not too hard to eye ball a pentagon.

Can't help with the other one.

Ian S C

Bazyle22/07/2018 14:42:15
4391 forum posts
184 photos

triwing? or tri-wing

avoids paying royalties to Posidrive and Philips I suppose

Edited By Bazyle on 22/07/2018 14:44:30

Michael Gilligan22/07/2018 15:33:51
12692 forum posts
551 photos
Posted by Bazyle on 22/07/2018 14:42:15:

triwing? or tri-wing


Bits are readily available, either individually or within sets like this: **LINK**


Muzzer22/07/2018 16:58:06
2904 forum posts
448 photos

That triwing thing is just gagging to be shown a sharpened masonary drill. You might almost say the same about the pentagonal one. Might be a bit of a sod to loosen if it's been in a pond for a while, so not convinced I'd try to make anything to fit.

There's also the TIG approach which comes with the benefit of applied heat....


Neil Wyatt22/07/2018 18:09:56
15581 forum posts
652 photos
73 articles

What photos?

I see nothing relevant in your albums...

Ah they are there now, page must have loaded incorrectly.

As Jason says, you aren't 'receiving' are you?

Edited By Neil Wyatt on 22/07/2018 18:11:31

David Standing 122/07/2018 19:21:02
1176 forum posts
43 photos

Nobody would want to 'restore' a Boris bike, unless they 'restored' it back to the pond it was dragged out of wink 2

Alan Johnson 722/07/2018 19:25:06
60 forum posts
13 photos

Dremel, angle grinder, oxy-acet spring to mind as suitable "spanners!"

Jon Lawes22/07/2018 20:43:47
271 forum posts

Only place I've ever seen Tri-wing is a BAE Hawk! Tri wing I thought look a bit narrower on the "wings" than that.

Michael Gilligan22/07/2018 20:53:36
12692 forum posts
551 photos

This is probably the most comprehensive and convenient reference list I have seen: **LINK**


Meunier22/07/2018 21:24:21
181 forum posts
1 photos
Posted by Michael Gilligan on 22/07/2018 20:53:36:

This is probably the most comprehensive and convenient reference list I have seen: **LINK**


Thank you for that MichaelG, an interesting run-down.

Simon036223/07/2018 11:59:40
142 forum posts
40 photos
Posted by Meunier on 22/07/2018 21:24:21:
Posted by Michael Gilligan on 22/07/2018 20:53:36:

This is probably the most comprehensive and convenient reference list I have seen: **LINK**


Thank you for that MichaelG, an interesting run-down.



Vic23/07/2018 14:05:35
1968 forum posts
10 photos

Wiki has the best listing of screw types that I’ve seen:


I’ve seen most types at one time or another but not the Bristol.

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