OldCoot

Trying to remove a 1st gen Dura Ace Crank arm. Having issues with the bolt that holds it in place and threads into the square taper spindle. The bolt head appears to be an odd size. 14mm and 9/16" sockets are too small, and 15mm won't fit past dust cover threads to reach the bolt. Did shimano ever use a bolt with a 14.5mm bolt head?

Thought about putting this in Bike Mechanics forum, but thought C&V might be more likely to actually know.

jeirvine 

I believe it is a 15, but you'll need a thin-walled socket.

repechage

Thin walled socket, or grind one down, Or a Campagnolo, TA or Park crank bolt wrench, 15mm- those all are "thin" walled.

merziac

You probably need a thinwall 15mm, might even need the Shimano version. If you have a cheap 15mm socket and a bench grinder you can put it on an extension and spin it against the grinder to thin it down, use a light touch and keep it spinning till you get it thin enough.

repechage

spin it with a drill motor. Spark city.
watch where the flammables are

merziac

And move them closer for even more fun.

OldCoot

14.5mm seemed wrong, just wanted to check. I have access to a lathe, so will go that way.
thanks

jeirvine 

I bought a cheap thin wall socket set at a home center for just a few $. Just take some calipers with you and find one with a 15mm with an OD under about 20.6 mm.

Chombi1 

Yes, you will need a thin walled socket to remove it.
Most socket sets sold these days are in the cheaper, "Home DIY" grades that mostly get their strength from having thick socket walls. Companies that make "pro" grade tools will usually have thinwall sockets in their tool model lines. The last time I had to find thin wall socket to use on a 14mm bolt on a Stronglight crankset was many years ago, and the right one from the Craftsman tool department at Sears. This was before they started making their tools in China. I noticed that the walls on their sockets are not as thin as they were, years ago

73StellaSX76

Six point sockets will often have thinner walls than twelve point, and be stronger with equivalent wall thickness. Check the six point options too.

repechage

Most of the cheapies are thicker though.

bikingshearer 

OldCoot - I've had a similar problem with a different crank, and a six-point socket of the correct size worked, If none of these other solutions work, let me know, I still have the original removal tool that came with my first-gen Dura Ace crankset and we can work something out. The crank disappeared on a stolen bike 30 years ago and I haven't used the tool since, but it worked then and ought to work now.

BTW, Shimano was just coming out with the Crane RD and Dura Ace line when I first got into this sport. Their stuff was a real bang-for-the-buck bargain for a cash-strapped teenager, and I loved how they included tools with their products. The Crane RD came with the proper allen wrench, the crankset came with both the crank puller and the little spanner thingy to hold the back of the chainwheel bolts to keep them from spinning when installing or removing. I never bought the brakes, so I don't know what they came with, and I don't remember what came with the hubs - possibly nothing. But the default setting was clearly to include the necessary tool, and I very much appreciated it at the time. The crank puller is the only one I have left, or at least that I can identify (an allen wrench or two might be floating around anonymously in my tool stash).

Hudson308 

Interesting. My Snap-On sockets are just the opposite. 12-points have a smaller OD.

Chombi1 

I quit using 12 point sockets long ago. There's just too much chances they might round off stubborn bolt heads and nuts......

Hudson308 

Agreed. Nearly all my sockets are 6-point, unless I need to get in somewhere tight, like an early Dura Ace crank bolt.