F4 BLT stuck/rounded bolt removal

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977EBC92-E4DC-4120-BB0A-A743D4436E8C.jpeg I’ve recently acquired an AMP Research B4 with an F4 BLT fork and noticed that some of the o-rings that protect the bearings are perished. I’ve ordered those but the next problem is getting out the rounded bolt heads in order to replace them.
IMG_4533.jpeg IMG_4532.jpeg
These bolts are like butter and there are titanium replacements available. I just need to get them out so I can replace the o-rings and install new bolts so the fork is serviceable in the future. A couple are functioning but the rest are beyond help.

Given that I have no proper equipment/skills or a work bench, just wondering if there are any retrobikers in the Heathfield/Hailsham/Hastings (all the Hs!) area that have the gear and expertise and who might be able to help me with my quest in getting the bolts out? Just need to make sure the threads within the linkages are preserved for prosperity.

Beers and snacks and a semi-able assistant (moi) will be supplied.

Cheers,

Tom
 
In the same circumstances I have bought Torx bits, taken a file to the ridges and tapered the ends a little.
Then hammer into the Allen head and remove with a socket spanner with the correct drive adaptor or a locked electric drill.
You need to keep pushing the bit in as you turn.

Obviously adding a little Plus-Gas an hour beforehand to the bolt to maximise your chances of it not being seized helps too.
 
Yeah. I’ve been in similar situations and tried the above without much success. Just a bit unwilling to go down that road again as it never ends well. I’m probably in the wrong hobby in fairness 😂. Simple mechanics like servicing I can do, but this is a little specialist and just want to achieve a good end result so I can do it justice.
 
I'd try the above. You've nothing to lose. I've found that you can sometimes just get a torx head to fit in there and the bolt comes out.

If that fails, but some easy outs. They require a small guide home to be drilled into the bolt. Then you screw in the easy out, it's a reverse tapered thread so will screw in then bind on the bolt head and it should then unscrew.

As the bolts are alloy, should be simple. I've got a stuck steel crank bolt I can't get a drill bit to make a joke in otherwise it would work. I've done the same on pace crown bolts.

You could get lucky and not need to drill if the easy out simply fits into the rounded Allen head.
 
Meant to ask about the ti bolts. I've a set of these forks and some b3s. I've got sets of nos original bolts but ti I like.
 
Where bolts heads site proud, I have successfully (and on several occasions) used a Dremel to cut a slot across the head of the bolt and used a flat blade screwdriver. Steady hand, one neat cut.

Try tapping in a Torx or next size up imperial key bit first though.

Cutting screwdriver slot can cause the head to snap off each side of the slot - so again, one nice straight cut across the middle, put downward pressure on the screwdriver and turn it with even torque - don't use an impact drill!

When you can get a recessed snapped stud out of an engine block - you fear nothing a mere bicycle can throw at you. Pah! There's always a way!
 
I'd try the above. You've nothing to lose. I've found that you can sometimes just get a torx head to fit in there and the bolt comes out.

If that fails, but some easy outs. They require a small guide home to be drilled into the bolt. Then you screw in the easy out, it's a reverse tapered thread so will screw in then bind on the bolt head and it should then unscrew.

As the bolts are alloy, should be simple. I've got a stuck steel crank bolt I can't get a drill bit to make a joke in otherwise it would work. I've done the same on pace crown bolts.

You could get lucky and not need to drill if the easy out simply fits into the rounded Allen head.
I'll give it a go, though the easy outs seem like a cleaner way to do things.

I didn't opt for ti ones in the end, as they were from the States and plenty pricey. Found a good chap on the AMP page on Facebook that has made/sourced some that he's selling in packs of 10. The all-in price is pretty much same for the price of three ti ones without the postage on top!
 
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Where bolts heads site proud, I have successfully (and on several occasions) used a Dremel to cut a slot across the head of the bolt and used a flat blade screwdriver. Steady hand, one neat cut.

Try tapping in a Torx or next size up imperial key bit first though.

Cutting screwdriver slot can cause the head to snap off each side of the slot - so again, one nice straight cut across the middle, put downward pressure on the screwdriver and turn it with even torque - don't use an impact drill!

When you can get a recessed snapped stud out of an engine block - you fear nothing a mere bicycle can throw at you. Pah! There's always a way!
Thank you for the tip. It's only two that are truly rounded. Don't like the sound of heads snapping, so might try tapping in a torx key before the easy outs.
 
hey, I had exact same problem, those aluminum screws in the AMP fork are crap, or at least a bad combination of aluminum screws in aluminum body, very likely not removed for decades but soft like butter.
I've sold the fork 😟

However, maybe I should have taken the challenge.

There are specific tools which could help a lot to remove such kind of stuck or broken screws. Just moderate skills are needed.

left cutting drills
e.g. https://www.amazon.co.uk/BGS-Drill-3-0-Titanium-Nitrided/dp/B0095KEXG8/ref=sr_1_1?
helping to move the screw at least in the right direction while drilling a hole into it.

or a full set incl. extractors to screw in
https://www.amazon.co.uk/TIVOLY-drill-bits-extractors-grey/dp/B076716GZH/ref=sr_1_1_sspa?

Amazon is not the best source of tools, I've just used it as an example.
 
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It's a challenge I will have to take up as I'm determined to keep the fork. That's very helpful thank you. I'll see if I can source them from a better supplier.
 

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