RSV4 Factory rounded off fork pinch bolt
Discussion
I was trying to remove the front wheel on my bike today and all was going well until I got to the last fork pinch bolt got the Allen key in and it was just spinning so must have been rounded off by the previous owner, or when I got my tyres changed.
Could anyone reccomend a way to get it out?, was thinking about drilling it but won’t that leave part of the old bolt in the fork leg?.
Could anyone reccomend a way to get it out?, was thinking about drilling it but won’t that leave part of the old bolt in the fork leg?.
Is the head proud or recessed? I'd be very wary of drilling it unless I'd got the fork leg off and in a pillar drill, otherwise the likelihood of drilling it central is limited.
If it's proud, then try tapping it round with a small cold chisel, or can you get some mole grips on it, or even welding something with a head to it (careful tho with heat and ally fork legs).
As above, you can get easy-out type things but you'd need a short squat one. You kinda need the reverse of these although I don't know whether they exist or what they're called:
https://www.amazon.co.uk/dp/B0000CCXVZ/_encoding=U...
If it's proud, then try tapping it round with a small cold chisel, or can you get some mole grips on it, or even welding something with a head to it (careful tho with heat and ally fork legs).
As above, you can get easy-out type things but you'd need a short squat one. You kinda need the reverse of these although I don't know whether they exist or what they're called:
https://www.amazon.co.uk/dp/B0000CCXVZ/_encoding=U...
Walter Sobchak said:
Here is a pic of the offending bolt:
Sorry I’ve no idea why the image is rotated it was the right way up when I uploaded it.
Only other thing I thought of was to hacksaw some cuts in it and try and unscrew it with a screwdriver?.
That's blatently been overtightened by some garage monkey, the ohlins fork bottoms are known for cracking if overtighened, they need just 12nm as per spec but 10nm is plenty.Sorry I’ve no idea why the image is rotated it was the right way up when I uploaded it.
Only other thing I thought of was to hacksaw some cuts in it and try and unscrew it with a screwdriver?.
This is what happened to mine (gen2 Tuono but the same model forks).
If yours have been tightened up enough to round off the bolt I'd be checking for cracks, the left one normally goes first as the metal is thinner (wider axle). By the way, a replacememt fork bottom is around £250-£300 fitted (with a fork service as the fork leg has to come apart)
+1 for the Torx.
Done this may times and works a treat. Doesn't have to be hammered in hard but just enough that it cuts into the internal faces to get a purchase.
As for cracking the front face, this is highly unlikely as the force is transmitted through the bolt into the rear threaded area.
And the reason these get graunched isn't usually because of over-tightening but because the bolt sits under the compression adjuster and needs a longer allen shaft to get to it. If you use the standard length socket mounted one the ratchet fouls the comp adjuster body and doesn't sit cleanly into the bolt. Half a turn later and bingo, you've buggered the bolt....
Aprilia... love 'em
Done this may times and works a treat. Doesn't have to be hammered in hard but just enough that it cuts into the internal faces to get a purchase.
As for cracking the front face, this is highly unlikely as the force is transmitted through the bolt into the rear threaded area.
And the reason these get graunched isn't usually because of over-tightening but because the bolt sits under the compression adjuster and needs a longer allen shaft to get to it. If you use the standard length socket mounted one the ratchet fouls the comp adjuster body and doesn't sit cleanly into the bolt. Half a turn later and bingo, you've buggered the bolt....
Aprilia... love 'em
f1nn said:
I had similar on my ZZR1400, I replaced with stainless steel versions.
Spray with brake cleaner, fill with the two part chemical metal you can get from places like Halfords and set the tightest fitting hex/torx key in. Wait to set, unwind.
This seems like a great idea.Spray with brake cleaner, fill with the two part chemical metal you can get from places like Halfords and set the tightest fitting hex/torx key in. Wait to set, unwind.
I've tried the torx for stuff like this, it never works for me. Drilling, omfg, nightmare, I am f
king useless at doing st like this. I will be trying your method. Also I don't even attempt doing anything like this unless its reasonably warm in the garage, I've literally found hex heads starting to mush up when its freezing in the garage but fall out when its warm.
Walter Sobchak said:
Here is a pic of the offending bolt:
Sorry I’ve no idea why the image is rotated it was the right way up when I uploaded it.
Only other thing I thought of was to hacksaw some cuts in it and try and unscrew it with a screwdriver?.
I'd dremel a slot into that, and use a screwdriver attachment for a drill with a socket set, or, as said above, carefully hammer a torn driver into it by just tapping it in slowlySorry I’ve no idea why the image is rotated it was the right way up when I uploaded it.
Only other thing I thought of was to hacksaw some cuts in it and try and unscrew it with a screwdriver?.
Heating it up first with a heat gun will help too, and try and get some WD40 or similar into it as that can help work it's way into the threads and loosen things up a bit
Edited by graeme4130 on Monday 13th November 13:27
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