Steering head spanner.

neptune

Esteemed Pedelecer
Jan 30, 2012
1,743
353
Boston lincs
I recently stripped down the steering head on my bike to grease the bearings. There are two nuts at the top of the steerer tube, which I need to lock-nut together. I can use an adjustable spanner on the upper one, but the lower one is a narrow nut. There is only room to get a slim spanner on it. A pressed out one would do. The nut measure 47 mm across the flats. I can`t find one on ebay. I don`t want to pay much, as I am unlikely to use it very often. Any ideas anyone?
 

Blew it

Esteemed Pedelecer
Jun 8, 2008
1,472
97
Swindon, Wiltshire
47 mm A/F is a very unusual size, I have never encountered anything larger than 40 mm A/F on a threaded headset.

By rights, you should be able to use an adjustable spanner on both nuts. The cone nut is first lightly tightened to allow free rotation of the steerer without slop. The tabbed locking washer is then fitted followed by the locknut which can then be tightened with the adjustable. The tabbed washer preventing the cone nut from rotating.

You may find when tightening the locknut, the steerer will then be too stiff to turn freely, the result of the thread clearance being taken up. The trick is to anticipate this when tightening the cone nut. Try tightening the cone nut for correct adjustment, then back it off a bit to allow for the additional pressure of the locknut.

You may find Sheldon Brown's article on the subject useful.

http://sheldonbrown.com/headsets.html
 

grldtnr

Esteemed Pedelecer
Sep 22, 2012
627
288
south east Essex
Shemozzle would be right, it is unlikely to be larger than 40mm, there is no other way to deal with locknuts on the steerer, ,bite the bullet & buy head set wrench, for your bike you will need 2, generally the top one is smaller than the bottom one , pressed steel ones are adequate if used with care, they wil still be cheaper than going to the LBS, and you will have satisfaction that you know that the job is done right!
 
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