A2 (304) stainless caliper bolts anyone used them???

Chat for Falco Owners.

Moderators: Aladinsaneuk, MartDude, D-Rider, Moderators

Message
Author
User avatar
old git
Clubman Racer
Clubman Racer
Posts: 335
Joined: Thu Apr 01, 2010 8:31 pm
Location: Worcester - UK

A2 (304) stainless caliper bolts anyone used them???

#1 Post by old git » Tue Jun 08, 2010 6:53 am

Posted on technical section, anyone changed from the crap stds. to stainless for this part please??
Hiding under a carpet of grey hair & lard.

User avatar
anzacinexile
SuperSport Racer
SuperSport Racer
Posts: 441
Joined: Mon Jan 15, 2007 11:00 pm
Location: UK South Coast

#2 Post by anzacinexile » Tue Jun 08, 2010 7:35 am

Oh yes - no problems

User avatar
mangocrazy
Admin
Admin
Posts: 3944
Joined: Thu Jul 17, 2008 3:24 pm
Location: Sheffield, UK

#3 Post by mangocrazy » Tue Jun 08, 2010 1:59 pm

No problem in finding SS bolts in the correct size for that application, but I've heard from a number of sources that SS bolts are NOT recommended for use in a high-stress application like that. You should really stick with Hight Tensile steel for caliper and disc bolts. Stainless is comparatively weak as metals go, and certainly not close to HT steel.

User avatar
anzacinexile
SuperSport Racer
SuperSport Racer
Posts: 441
Joined: Mon Jan 15, 2007 11:00 pm
Location: UK South Coast

#4 Post by anzacinexile » Tue Jun 08, 2010 4:19 pm

The standard bolt size in SS is more than adequate for the stress's involved. My only advice is to get decent quality SS bolts, not the cheep shit crap that go-faster bling merchants sell - very poor quality of steel

User avatar
old git
Clubman Racer
Clubman Racer
Posts: 335
Joined: Thu Apr 01, 2010 8:31 pm
Location: Worcester - UK

#5 Post by old git » Tue Jun 08, 2010 5:31 pm

OK, thanks chaps for the replies.
Had already been noted that the tensile strength of SS is lower than high tensile OEM fittings, but after a bit of digging,
  • Metric Class Marks on Head Material Tensile Strength Yield Strength
    N/mm2 psi N/mm2 psi
    8.8 8.8 Steel 800 116,000 640 93,000
    10.9 10.9 Steel 1040 151,000 940 136,000
    12.9 12.9 Alloy Steel 1220 177,000 1100 160,000
    A2-70 A2-70 302 Stainless 700 102,000 450 65,000
    A4-80 A4-80 316 Stainless 800 116,000 600 87,000
So, standard A2/302 stainless is a little down on tensile strength against HT 8.8 but A4 / 316 has the same at 800N/mm2
In which case, it would seem that 316 should be OK for the application and would not old corroded 8.8 steel be down on strength anyway as it has oxidized/rusted.

Yeild seems to be where the components start to deform, rather than shear, again 316SS seems to be close enough as not to matter.

Know I am sad, but found this & the replies all most interesting.

Thanks,

Sorry, table don;t line up right when posted
Hiding under a carpet of grey hair & lard.

User avatar
D-Rider
Admin
Admin
Posts: 15560
Joined: Wed Jan 03, 2007 1:09 pm
Location: Coventry

#6 Post by D-Rider » Tue Jun 08, 2010 6:56 pm

The yield point is where it snaps under tension (after it has been stretched somewhat)
:smt002
“Scientists investigate that which already is. Engineers create that which has never been.”
-- Albert Einstein

User avatar
old git
Clubman Racer
Clubman Racer
Posts: 335
Joined: Thu Apr 01, 2010 8:31 pm
Location: Worcester - UK

#7 Post by old git » Tue Jun 08, 2010 7:33 pm

D-R, thanks, interesting what you can find once you get a start on something.....
looked at Tastynuts / Probolt websites, hiden under the questions & answers section they confirm their ss fixings are 316 which is as good or exceeds the 8.8 HT fixings used as OEM componenets.
Hiding under a carpet of grey hair & lard.

User avatar
MartDude
Admin
Admin
Posts: 2857
Joined: Tue May 26, 2009 11:36 am
Location: South Shropshire

#8 Post by MartDude » Tue Jun 08, 2010 9:44 pm

Thanks for that OG, really useful post. I need to replace some of my fasteners - the plated bolts are pitting, rusting and definitely not as pretty as they should be.

Prompted me to do a bit of searching, & found this stockist - prices look reasonable, although the site doesn't say anything about a minimum order value
http://www.felixfastenersuk.com/A4.htm
http://www.felixfastenersuk.com/PDFs/webpricelist.pdf

Slight hijack - can someone tell me what the name is of those little caps with springy tabs that one pushes into the hex sockets of socket screws, in order to prettify them? Better still would be a supplier.

Also, where can I get grease nipples for my knees?
It flies sideways through time
It's an electric line
To your zodiac sign
I've got a Black and Silver Machine!

User avatar
Aladinsaneuk
Aprilia Admin
Posts: 9503
Joined: Wed Jan 03, 2007 10:37 pm
Location: Webfoot territory

#9 Post by Aladinsaneuk » Tue Jun 08, 2010 9:46 pm

MartDude wrote:Also, where can I get grease nipples for my knees?
ask hanna


Let's face it, you wouldn't go to a nurse to get good advice on a problem with a Falco - you'd choose an Engineer or a mechanic...


User avatar
mangocrazy
Admin
Admin
Posts: 3944
Joined: Thu Jul 17, 2008 3:24 pm
Location: Sheffield, UK

#10 Post by mangocrazy » Tue Jun 08, 2010 9:47 pm

In that case I stand corrected. I'd much rather use SS fasteners than steel, as they not only look better, but last way longer. And A4 (316) SS is even more corrosion resistant than A2/302; I believe its specified for use in marine and other harsh environments (like British roads in winter)....

If it was race or regular trackday use, I'd still prefer HT steel, though...
Last edited by mangocrazy on Tue Jun 08, 2010 9:49 pm, edited 1 time in total.

wayno
SuperBike Racer
SuperBike Racer
Posts: 904
Joined: Thu Apr 15, 2010 1:55 pm
Location: Buckinghamshire

#11 Post by wayno » Tue Jun 08, 2010 9:48 pm

Probolt do stainless bolts that can be used in high stress areas i.e. caliper bolts, I think they have toi be 316 grade, not the cheaper 304. I try to replace as much as possible with stainless on my bikes, it helps next time you need to strip anything.
Pass me a hammer, a spanner and a cuppa

User avatar
Kwackerz
Admin
Admin
Posts: 8362
Joined: Thu Dec 14, 2006 6:16 pm

#12 Post by Kwackerz » Tue Jun 08, 2010 10:05 pm

MartDude wrote:Slight hijack - can someone tell me what the name is of those little caps with springy tabs that one pushes into the hex sockets of socket screws, in order to prettify them? Better still would be a supplier.

like these?

CLICKY

dunno... well, of a UK source anyways..
Never ride faster than your guardian angel can fly

User avatar
MartDude
Admin
Admin
Posts: 2857
Joined: Tue May 26, 2009 11:36 am
Location: South Shropshire

#13 Post by MartDude » Wed Jun 09, 2010 1:21 am

Aye, them's the buggers. Ta.
It flies sideways through time
It's an electric line
To your zodiac sign
I've got a Black and Silver Machine!

User avatar
old git
Clubman Racer
Clubman Racer
Posts: 335
Joined: Thu Apr 01, 2010 8:31 pm
Location: Worcester - UK

#14 Post by old git » Wed Jun 09, 2010 6:11 am

mangocrazy wrote:In that case I stand corrected. I'd much rather use SS fasteners than steel, as they not only look better, but last way longer. And A4 (316) SS is even more corrosion resistant than A2/302; I believe its specified for use in marine and other harsh environments (like British roads in winter)....

If it was race or regular trackday use, I'd still prefer HT steel, though...
Check out probolt, says they are 316 SS & can be used on track, spec equals or exceeds that of the standard 8.8 HT
Diff. is that now we know 316SS is good to go, can source from cheaper supplier not from robbers.
Looked at the SS front axle nut on their web, £25! guess who's talking to the engineering dept. at work later for their supplier!

Do note chaps that some of the bolts have the fine pitch thread, like the caliper mounting bolts & some are standard metric thread, so just double check before you go placing any orders on tinterweb suppliers.
Hiding under a carpet of grey hair & lard.

User avatar
Jadaris
Malteaser
Posts: 384
Joined: Fri Sep 04, 2009 9:00 pm
Location: Isle of White

#15 Post by Jadaris » Wed Jun 09, 2010 7:54 am

Aladinsaneuk wrote:
MartDude wrote:Also, where can I get grease nipples for my knees?
ask hanna
when you're dribbling too much?....
:smt016
Cheeky sod :smt002

Post Reply