randynewmanscat
Veteran
Well....?
Uh Oh. Snapped Off A Hex Key In A Bolt Head.
- Thread starter Lovacott
- Start date
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stoatsngroats
Legendary Member
It’s better than Saturday night ITV! 
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Lovacott
Über Member
Ming the Merciless
There is no mercy
The magnet has however stripped all the spokes from the wheels and there’s a pile of wrecked cars outside.
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Lovacott
Über Member
It seems like a good idea, but it would have been better if rather than a 2mm hex, it had a thumb turn instead. The range of adjustment is very small and is facilitated by aligning two marks when the front mech is in the big ring trim position. Luckily, it's pretty easy to get it right just by pulling the cable through by hand and clamping when there is no slack.
The other issue is that the bolt head is round and recessed into the mech housing so it can't be adjusted or removed with pliers or slotted and removed with a screwdriver.
There is no scope to fit a standard barrel adjuster at the control lever end (which is where front mech adjusters normally live).
Worse case for me is I'll have to buy a new mech for around £30.
Gunk
Guru
That’s what I would do
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Lovacott
Über Member
I had to take the mech off a few weeks back to fit a chain deflector and when I re-fitted the cable and clamped it up, it didn't need any adjustment.
The adjustment I did last weekend (when the hex key snapped) was only very minor which was probably just the cable "bedding in" on a new bike.
If it needs adjustment in the future, I'll try it first by simply pulling the cable through and re-clamping (as I did when I fitted the deflector).
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Lovacott
Über Member
I will wait until I go over a pothole and the bike shatters. Then I will be able to retrieve the screw from the pile of CF dust.
randynewmanscat
Veteran
Bugger! You are probably at the stage where you think, ah well its right for now I'll deal with it later. If you want to be satisfied that you gave it a good try you could have a pop at dislodging it with the tip of a metal scriber, trying to pick it back on itself.
I think you will be waiting until a new cable cannot be ignored somewhere in the future. By then you will found somebody who owns a column drill and decent drill vice, then it will be sorted.
T4tomo
Legendary Member
is it flat bars or drops? Gear levers from flat bars normally have on the control, but on drops where the gear cable runs under the bar tape on most new bikes, you can use these in the cable run
https://jagwire.com/products/small-parts/inline-adjusters
or similar in the cable stops on the down tube (if you have them, internal cable runs have done away with them on some frames).
cheaper than a new mech and easier than pissing around with a 2mm allen key
Shimano incorporating the cable tension adjustment into the mech seems a poor "upgrade" to me
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Lovacott
Über Member
Drop bars with internal cable routing but I could make these work.
Shame the site doesn't seem to have a download for them (showing dims and fitting detail etc.).
T4tomo
Legendary Member
just google inline gear adjusters or barrel adjusters. assuming you are running 4mm outer gear cable then you need the 4mm models (5mm is for Brake cables) quite simply the gear cable just inserts at either end (no ferule needed, but a good clean straight cut is advisable). you twist it and it lengthens / shortens your effective outer cable length and thus adjusts the cable tension.
very easy to fit. Fit them in the run between the bars and where the cable enters the frame:
Remove inner cable (you can just retract enough so it isn't in the bit your snipping, but still in the run beneath the bar tape) snip and tidy ends of your outer, insert and re thread the inner cable - there is normally some sort sort of bung you can remove to find the inner where it exits the frame, and reattach inner to the mech in question.
very easy to fit. Fit them in the run between the bars and where the cable enters the frame:
Remove inner cable (you can just retract enough so it isn't in the bit your snipping, but still in the run beneath the bar tape) snip and tidy ends of your outer, insert and re thread the inner cable - there is normally some sort sort of bung you can remove to find the inner where it exits the frame, and reattach inner to the mech in question.
