Stainless bolt grades?

[CornishPete]

Hi Everyone, I've just bought myself a new toy. She's knocking on a bit but in good shape for her age. I think she'd look a lot better without all the bolt heads being rusty so I'm thinking of swapping them out for stainless. I know you can get kits for road bikes but not a 20 year old gas gas so I'll get them separately. From past experience stainless bolts/screws have been softer than normal steel. For ratings I'm not too bothered but thought it might be a good idea to get important ones the right grade. Is there a stainless equivalent standard bolt grades?

 

[atomant48]

ARP do a lot of different bolt styles and sizes and are very clear about their grades - might be an option depending on budget - some of them are not cheap but I guess you only buy them once.

 

[mike os]

Generally only available in a2 or a4 (304 and 316)

304 is slightly tougher and therefore less likely to shear or round off, 316 more corrosion resistant

Personally I avoid both on structural or critical applications

Chrome or a home chroming kit might be a better option for the above

 

[james butler]

stainless bolts usually aren't softer than steel bolts, they're normally harder and as a result don't take shock or stress very well in comparison to the steel hence why you should never use a stainless bolt in place of normal steel structural and critical applications like mike os has said

 

[Mick Annick]

Well, if you want to improve your riding you need them colour-coordinated at the very least - https://www.gwr-fasteners.co.uk

But for real performance improvement you need titanium! https://www.pro-bolt.com

 

[mike os]

Personally I would just replace with bzp... not expensive and you can get the correct grade

 

[Morris]

As mentioned ARP do SS bolts rated at 170,000psi tensile. Best be sitting down when you get a price.

 

[CornishPete]

stainless bolts usually aren't softer than steel bolts, they're normally harder and as a result don't take shock or stress very well in comparison to the steel hence why you should never use a stainless bolt in place of normal steel structural and critical applications like mike os has said

I use stainless screws for external applications and always found the heads round off much much easier than bzp so assumed they were softer! I think replacing with bzp is a good shout, the bike is 20 years old so I assume the bolts are too. Bzp will look nice and shiny for a reasonable time.

 

[ronan]

Bah, get the titanium ones !

 

[Munkul]

You can get stainless fasteners cold-worked in 60 or 70 strength grades. At work we use A4-70 any place where atmospheric corrosion of piping is a problem, or for any severely corrosive/dangerous product piping.

For the record, an 8.8 has tensile strength 820 MPa, an A4-70 has tensile strength 700 MPa, so there's not a massive load of difference. The bigger problem usually is dissimilar metals corrosion... but usually more a problem when you put steel fasteners in stainless...

 

[bs2236]

We use a lot of A4-80 but for high shock loading areas we use BUMAX 109, these have a higher yield strength and a lower magnetic permeability. Really nice fixings to use and very high quality with non of the gauling issues of A470 & 80 flavours.

 

[ronan]

Get yourself a tube of copper or lithium grease if you do buy stainless bolts.