Brake disc bolts sheared off, easily !!!

[pae]

Jeepers.... took both front discs off my 650Z today to start cleaning up the comstars and 2 of the 5 bolts just sheared when untightening the nuts. Both of them broke off in just inside the nut. I wasn't putting any real pressure on either.

You might want to check yours...

Phil

[bandwidth69]

Are the bolts steel or alloy? Scary!

[Volker_P]

That really sounds dangerous. Maybe corrosion due to contact of different materials. Do you have a picture of the bolt and the thread in the wheel? I had a look in the manual, they get only about 30Nm. Maybe somebody has overtightened them, however I would expect this would rather damage the thread in the wheel than the bolts.
BTW: your project progress is quite impressing. I looks like it could be worth to care also a bit for my front forks.

[pae]

They're steel bolts, the normal Honda type with the figure 8 on the head, so I'd think they are standard bolts and not a particularly high grade.

They are through bolts (M8 x 100 hex head setscrew) that pass right through the disc, plain holes in the hub (Comstar wheels), through the other disc and then have a flanged nut on the other end. The thread has sheared just inside the nut. I'm amazed how easliy they sheared.

I'll post some pics when the cameras batteries are recharged.

regards, Phil