I removed both wheels yesterday to take them to get new tires mounted.  When I tried to remove the front brake caliber bolts, they were stuck so bad that I snapped my allen wrench bit (ratcheting screwdriver) in half.  

I managed to carefully slide the wheel down and around the caliper and get it off, but I don't think it's gonna go back on without getting the caliper out of there.

Any suggestions short of drilling the bolts out?  If not, anybody know what size/type bolts I need to get to replace the ones I drill out?

Bump.

Spray some Liquid Wrench on the bolts, to help loosen them up?

I'm gonna try my brother's impact wrench as soon as I can find a hex bit the right size.  Hopefully the combination of that and the Liquid Wrench (never used anything like that before) will get the bolts out.

My last ditch effort before drilling is heating.

I have freed a few stuck bolts by heating them with a soldering iron and then letting them cool. I think the expansion/contraction  process can help them break free. Just don't do it after applying lots of flammable lubricant  

The caliper bolts are held in with Loctite, a kind of thread fixing 'glue' that prevents them working loose under the severe bumping and jolting that they suffer.  

You can break the Loctite's hold by hitting the bolts sharply with something like a nylon or brass-headed mallet.  They should then be easier to undo.  With care you can use an ordinary steel hammer to do the same thing, but you run a greater risk that you will break or crack the caliper bolt mounting lugs in the process.

Be sure to use Loctite again when you re-install the bolts.  Don't be tempted to grease them to make them easier to remove them next time (as I have seen suggested on the board   ).  If you do, they will choose their own time and place to remove themselves!

well, that explains how I sheared off the head of the allen wrench.  Just tap the head of the bolts with a small hammer, eh?  

If you are going to Home Depot you might have trouble finding a 8mm allen socket attachment...that's really the way to go IMHO...the less beating with a hammer you have to do on your bike the better...Just need a little more leverage and a little stronger metal than they typically use in allen wrenches.. well, if you do find one at Home Depot you might have to buy a whole set...and their metric selection sucks.  You might be able to find them sold individually at NAPA...they actually have a pretty good selection for sockets...1/4" to 3/8" to 1/2" adapters, extensions, etc.

Thanks Dom!  For whatever dumb reason, I hadn't thought of looking at an auto parts store...sometimes the obvious just soars by

Quote from: Richard UK
Be sure to use Loctite again when you re-install the bolts.  Don't be tempted to grease them to make them easier to remove them next time (as I have seen suggested on the board   ).  If you do, they will choose their own time and place to remove themselves!

and this is why every bike i have has the front caliper bolts safety wired!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! before i ride it.

It's possible that a previous owner used red loctite on the bolts. About the only way to remove them will be with heat. The axle nuts on my truck had red loctite on them. A 6 ft cheater bar and 3/4" ratchet wouldn't break them free. As soon as I applied a little heat they came loose like butter.

Derek

took scratch's suggestion and got some liquid wrench at Walmart.  Picked up a cheap set of allen sockets and (finally!) a cheap set of metric sockets.  Both sets were Stanley and were around $12 each.

Finally got the damn things off around 11pm tonight.  Got the wheel back on and the new pads should be in tomorrow.  Now if I can just get it to start, I'll have a huge smile on my face.