HI,
I have a problem with the disc bolts on my 1990cbr 1000f, i am struggling to remove them (have got three out of the rear disc) not tried front yet, doyou think it i should drill them and retap, or has anyone any other suggestions, as i really need these out to get the wheels powder coated, as i am giving the bike a major overhaul as it is 16 years old . would be grateful of any advice
cheers nasty

 

are you talking about the pad pins, or the caliper bolts?

 

i'm thinking the rotor bolts...
use some WD40, let her sit...

 

Are the heads already mangled ? If so drill n tap is best. If your havin em powdercoated anyway, you might try a lil heat around the area if you have a o/a torch or propane. Even one of those small butain jobs will do to get the area around the bolt hot. If you can still get a grip, or make what remains gripable, try the heat. If you have NO way of twisting them, heat isn't gonna do diddly. You want the bolt (remains of one) to be relativly cool, so get some vise grips on it and leave em on while you heat it to keep the bolt as cool as possible. Use a rag cuz the v/grips will get warm If it starts to move, keep it hot and keep going, don't snap it cuz you let it cool. If it cools...... heat it up again ! Not talking red hot, not even close to hot enought to damage it. Some times a lil heat will go a long way toward getting a seized bolt to budge. Another "old head" trick is to warm it... then cool it w/a kids crayon, stuffing as much wax as possible into the area like you would w/ wd40, then let it cool just a bit. The wax, w/heat will get into places lube spray can't. Don't forget that heat cycles alone can help to free it up, so don't give up on the first try, some soot won't hurt a thing if your coating them anyway.

If you can't seem to get much heat in the metal, you might have to remove w/ever coating there is so you can get direct contact; flame to metal. Not all of it, just where you need to heat. A pic would help too !

When your heating it, it might seem kinda like over-kill, but the idea is to get the surrounding metal hotter, and hot faster than the bolt. If there both the same temp cuz you heated it slowly, it prob won't work.

 

"Liquid Wrench" is like WD 40 only a much stronger solvent. I used LW to break rusty bolts loose on a 1946 D7 Caterpillar tractor. I was impressed with how well it worked. Like TSC says, let it sit for a while. This is all assuming you can get a grip in the bolts.

 

I tried LW once on a crap load of screws that were stuck due to two different metals being used (brass and aluminum). They were tighter then a nuns whoha. To get them off, I just drilled off the head of the screw and then removed the part I needed removed. Then I took pliers to the remaining headless threads and removed what was left of the screw. I did about 15 of these dumb things and I never had to drill out the threads. It was a LOT of work, but it was nice being able to keep the original threads.

 

I've always had excellent luck with "PB Blaster" you can get it at any auto supply store.I've never found a bolt yet that wouldn't come out after you sprayed it with that.I also sometimes have given the head of the bolt a whack with a hammer after I sprayed it.It helps to break loose the rust,corrosion,or anything else.Try PB before drilling or heating,those are your last choises when removing a bolt.

 

Thans for all your ideas , will soak in wd 40/ penol, will try the het treatment as a last resort
cheers nasty

 

make sure you use some thread locker when you put it all back together. don't want those coming loose on you.

 

Hi all, thanks once agaian for the suggestions, i have now sucesfully removed the bolts, by tack welding some 6mm(1/4 inch for you americans) nuts onto the head of the old allen bolts and used a socket and t bar wrench , i think it was a combination of the heat via the welding and being able to geta decent grip on them that worked ,i now need to locate some new bolts preferably in s/s/ any ideas
cheers nasty