Rear Disc Mounting Bolts

[Neon Knight]

First of all thanks to all who chipped in with ideas regarding my rear caliper issues. Most helpful and in the end I managed to resolve the problem. Cheers  . And now, another problem that I would like some advice on. I have recently aquired a second hand but in very good condition rear disc.  My one is the original and is well past it's best by date, in fact it was badly scored when I bought the bike many many years ago. I was advised to put sintered pads on and eventually they will wear away the worst of the damage, which happily enough they did. However, now it is time to replace the disc and I am buggered if I can get the mounting bolts to budge even a millimetre. I have used impact drivers, impact wrenches, releasing oil (silkopen), wf40 but no joy at all. Does anyone have any ideas as to how I can get them off ? The bike is well old now, registered in 2000 and I bought it in 2004 and its an everyday bike so its seen plenty of bad weather and miles. Please HELP  :'(

[griff86]

Lots and lots of heat usually works.

Mine were really stuck, even using oxy-acetylene to heat them all up 2 wouldn't budge, I had to drill them out.

The issue is that the threads are exposed through the inside of the wheel.

[Neon Knight]

What exactly do I need to heat up, how hot ? and for how long ?  :'(

[griff86]

The area surrounding the bolt, as hot as you can get it, five minutes plus with a gas blow torch. I've got them off with a few minutes blast of an electric heat gun before but that was on different bikes.

[darrsi]

I tried all the above, with no joy either, I ended up buying a second hand wheel and getting the tyre swapped.
Because the rear disc isn't in 2 parts like the front (inner/outer) the heat transfers to the rear wheel hub and fuses the bolts.

[sinto607276]

Just posted this in what have you done with your fazer today....Reply #16  by sinto on 16 Jun, 2015 20:56
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Quote from: Neon Knight on 16 Jun, 2015 17:57
Shouted at her, cursed her, kicked her back wheel. And all because I cant get the rear disc mounting bolts off so I can change the disc.
Have you tried tightening them a wee bit to break the seal?  Just a wee touch, then you should be able to release them, soak them with some loosing oil beforehand too.

[risticuss]

As others have said, the only way is heat. I managed to get 3 out with a small kitchen blow torch but the other threes heads just chewed up.
I ended up drilling them out anhelicoiling the wheel.

I don't know how 6 bolts made of cheese can possibly be that good at holding a disc on, but apparently they can.

[greenman]

I had same issues, tried everything but they wouldn't budge. Ended up taking the wheel to my local bike shop, Alf's motorcycles in Worthing, they ended up drilling 2 out and the rest came out with the wheel thread bonded to them, then replaycing the threads with steel threaded inserts. Cost me 60 quid a couple of years ago. Front ones came out ok.