What the hell happened to my steerer?!

Just took the lockring off my head set on my gitane and the top of the fork steerer looks like this!

Unfortunately the lockring will not go back on . I'd consider chopping the steerer down below the damaged part but the headset has no spacers so it end up too short.

The only was I think this can have happened is that the stem is a standard diameter (22.2mm) and is too big for the french size steerer tube (22.0mm dia) and has somehow been forced in . Unlikely, but its always been very difficult to get in and out. and may have damaged the steerer. It has split just where the flat part of the steerer is so its fairly thin

Has anyone got any suggestions on how to fix it. Don't really want to spend on a new pair of forks and headset as this has now become my beater, and the frame's probably worth less than the cost of new parts.

any suggestions?

thanks

3 Attachments

Tap the damaged area gently back until the stem fits.
'clean up thread a bit' with a small file.
disassemble the spacers.
use a lube / cutting fluid when undoing the top cup, cleaning up the thread as it comes off.
If the split is only a few mm, reassemble.

<< Will fix 4 u 4 beerz..>>

Thanks will try that tonight , hadn't thought of unscrewing the headset fingers crossed !

Just took the lockring off my head set on my gitane and the top of the fork steerer looks like this!

any suggestions?

The pressure of the quill stem expander bolt can apparently split steerers on the thinnest point If you didn't have the stem very far in.

As for solutions, if you ditch the centre-pull caliper for a side pull you could remove the steerer-mounted cable hanger, lowering the stack height be a few mm. You could then chop the damaged part of the steerer off and have nice intact threads to screw the lockring onto.

Cheers that may be the answer if I can't re thread it

Ok so managed to get the top cup off and it will thread back on ok. But the lock ring won't. I tried a lock ring from another frame and it did go on!

To add to the confusion the problem bike is french which I according to sheldon has different threading. So why did the other locking ( from my pinarello ) fit? I didn't put it on far in fear of damaging the thread but it didn't seem to offer any resistance.
Is it just a case that the original locking was knackered ? The thread looks ok to me ...

Now I'm confused!

Try fitting it on at an angle.
If not, fettle with a file a bit until it does.

I've tried but it doesn't want to go on. Will I damage the threads on the fork if I use and iso threaded lockring ? (I don't mind if it rethreads the lockring - I may be able to find one in a spare parts bin at my local lbs