Brake disk bolts

[tatters]

I need to get hold of some new 8x25mm brake disk bolts (12 per disk) as most of the old ones had to be removed with a cold cheizel and hammer.

As far l can remeber brake disk and caliper bolts are high tensile steel bolts but l can,t find any metric ones at work we only have 316 stainless steel bolts (food/medical/marine grade) in all metric sizes up to 12mm, would they be safe to use them or will they not be able to take the shear load of a brake disk?
____________________
Past:NRG50,AF1125(x2),NSR125RR,ZZR250,CX500,VFR400,KR1S,ZZR600(x2),CB400N,YZF1000(x2),KH125,Z200,FX400R,CBR954RR(x2)GPZ500S,GT550,VFR750F(x2),RD350N,XR650R,CBR600F,CB250,KDX250,YZF750R,CRM250,400EXC,KLR650,TTR600RE,DR350S,R100GSPD,RGV250,VMAX1200,DL650,KZ750 Present:G650XC,C12,CRF450X,1190ADV

[JGY6000]

try https://www.hyperbolt.com/ top guys, there only round the corner from me but they post out stuff aswell and most of them are bikers!

[tatters]

[JGY6000]

thats becuase their titanium

[Delvard]

[Superlight]

Don't forget the thread lock.

For next time, you might find a bit of careful blowtorching removes the need for the hammer and chisel. The aim is to melt the thread lock without melting the tyres!
____________________
You only need two tools: WD-40 and Duct Tape.
If it doesn't move but should, use the WD-40.
If it shouldn't move but does, use the Duct Tape.

[edd]

316 stainless should be easily strong enough for disc bolts. I totally agree those discs are a bitch to get off. Ive just been taking the discs off a thundercat wheel, and even wiht the aid of a blowtorch, penetrating oil, and a decent set of allen sockets 3 bolts are rounded
____________________
Bluespark Automotive - Diesel Tuning for Performance and Economy

[Superlight]

Sure are a pain. A mate of mine broke one of my allen sockets changing a disc, but that was before we realised they were thread-locked!

I wouldn't want them coming loose while I'm riding though
____________________
You only need two tools: WD-40 and Duct Tape.
If it doesn't move but should, use the WD-40.
If it shouldn't move but does, use the Duct Tape.

[ZRX61]

[stinkwheel]

A 12.9 high tensile steel bolt has a tensile strength of 1200Mpa and will permanantly stretch at 90% of the proof load stress.

316 stainless has a tensile strength of 580MPa and will permanantly stretch at 55% of the proof stress. That makes your stainless bolts roughly equiuvalent to a grade 6.5 steel bolt.

At a pinch you could use grade 8.8 bolt to hold a disc on. It is probably more tolerant of cack-handed tightening (less likely to unscrew itself if you undertighten it) but would ideally be replaced after each use.

12.9 is more appropriate, 6.5 is way-out.

stinkwheel
Slow to reply coz he has been educating himself about different grades of bolt and their properties. They say you learn something new every day, I was cutting it fine today though
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[tatters]

I got a box of 100 Unbrako 8mmx25 Button Head Allen Bolts with a rating of 12.9 today for £7


Saved me a few quid insted of buying titanium ones at £4.70 per bolt
____________________
Past:NRG50,AF1125(x2),NSR125RR,ZZR250,CX500,VFR400,KR1S,ZZR600(x2),CB400N,YZF1000(x2),KH125,Z200,FX400R,CBR954RR(x2)GPZ500S,GT550,VFR750F(x2),RD350N,XR650R,CBR600F,CB250,KDX250,YZF750R,CRM250,400EXC,KLR650,TTR600RE,DR350S,R100GSPD,RGV250,VMAX1200,DL650,KZ750 Present:G650XC,C12,CRF450X,1190ADV

[owdamer]