Topic: Fork screw will not break loose HELP!!

[76four]

I am trying to remove the allen rench screw on the under side of my forks on my 76 cb550.  I watched a video of it all being dissasembled in order to replace the fork seals.  Well I used an allen wrench to a impact wrench like in the video.  It was a 6mm allen wrench, which is the right size.  It ended up rounding off my allen wrench and partially stripping the screw.  From what I could see in the video it was not a reverse thread or anything.  Now what options do I have?  Heat it up? Try it again with a different allen wrench? drill it out?  The allen wrench had so much tork put to it that it twisted.  Any recommendations?

[dave500]

with a punch that fits over the hex hole but seats on the bolt head give it a good smack,then use a better allen socket wrench on it and a breaker bar.

[ekpent]

Really only get one good chance at those,don't skimp on good quality allen bits.Worst case scenario is you will have to drill off the head.The allen is looking pretty rounded Take it slow and don't be to aggressive,just till the head pops of. Its usually the head of the bolt more than the threads that get seized so threads should come out easily after drilling.Along with a new bolt,which you will probably want either way, you will probably need a new copper crush washer also.

[Bodi]

The only way I've had success with these is using an air impact wrench, set to a low enough torque so the head is not destroyed. With a quality impact allen driver tip (I have Snap-on, any mechanic quality brand should be good) after a few seconds of hammering the screw just zzzzzits out. Using  breaker bar is rarely useful. The hand impact wrench should work OK but holding the tube is an issue and you still need a very good quality allen tip made for impact use. As you found out the "normal" ones fail under serious impact abuse.
Heating the fork end can't hurt. The bolt head is probably stuck to the leg, the lock piece it actually screws into is soaked in oil (hopefully!) and should not be corroded at all.

[KingCustomCycles.com]

I have driven properly sized, high quality "star" bit into the damaged allen head.  I then use a 3/8" drive ratchet to turn the bit. 

[ekpent]

Good suggestion King-kind of like an extractor.

[76four]

As always great advice everyone.  I will give it another try with your suggestions. 

[76four]

Victory!! I don't know if it was a combination of everything I did different or just one determining factor but they came off.  I ended up spraying liguid wrench around the screw and let it sit over night.great stuff by the way.  Then this evening heating the screw then scorching it with a wet rag.  Then used a new (quality) craftsman allen wrench as suggested and turned down the impact wrench to let it ratchet it more suggested as well.  And they spun out without any effort.  Thanks again for all your advice.