Page 1 of 2

Advise please re new M8 Button Head Bolts for PM tuning Disc

Posted: Sat Jan 21, 2012 6:37 pm
by bazman
Have SIP tubeless rims , need to swap over securing bolts on PM single disc brake , button head m8 thread, now do i need a specific hardened bolt? Or will any do, stainless etc ?
Thanks Baz.

Advise please re new M8 Button Head Bolts for PM tuning Disc

Posted: Sat Jan 21, 2012 7:05 pm
by soulsurfer
No not stainless. You really need a high tensile bolt, have a look on eBay ;-)

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 7:18 pm
by bazman
Thanks Mike.

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:04 pm
by tonydevon
I dont know,but best check before you spend any money, disc bolts are usually shouldered? unless they are centred on the hub?

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:10 pm
by shocky
the bolts on my ped are 10.9 tensile strength that or higher should be ok

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:14 pm
by shocky
just check if the old bolts have a shank (unthreaded bit near the bolt head) on them ? if so MAKE SURE THE NEW ONES DO AS WELL

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:42 pm
by tonydevon
thats what I was saying, usually they will be 8mm thread with a 10mm boss, this is what the disc is held by, as its not good practice to have it held by a threaded section

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:47 pm
by mark
The pm tuning disc is a sheet of ally with 4 button head bolts to hold the rim on these are the ones he is replacing not the disc bolts which I believe are std bolts as well

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 8:54 pm
by wack 63
The bolts are threaded all the way because they screw in from the back of the centre spinner therefore you need to fit the rim on them and measure how longer the new ones need to be. At a guess the normal ones are 25-30mm so depending how thick the rim is this will show what you need. Pretty sure they are also 8.8 tensile,if not sure ask Frank.

Re: Advise please re new M8 Button Head Bolts for PM tuning

Posted: Sat Jan 21, 2012 10:46 pm
by bazman
Yeah lads it is to secure the rims to the hub part, just had a look and 25mm standard ones and 10.9 printed on top as you can see in the following photos. All i can see on ebay are black ones and need bright as pictured will measure 2moz and see what size i need.
Image
Image