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Hey.

I am restoring my 750SS and a lot of the bolts are corroded and overall in bad shape. Would it be a good idea to swap them out for stainless steel bolts? I can get grade 10.9 and 12.9 ss bolts in practically any size and they seem to be good quality too. As I understand correctly, the grade shows how though a bolt is? Would it be suitable to use such bolts for, example, fastening brake rotors or on the triple clamps?

I would get them re-plated but practically no-one in my country does zinc-plating any more.

Thanks a lot.
 

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You should probably get familiar with the principles of galvanic corrosion to better understand where and why Ducati uses zinc plated steel fasteners (and purposely not stainless) to sacrifice the fastener plating to corrosion instead of the expensive aluminum parts that they thread into.

https://www.ducati.ms/forums/showthread.php?p=689655&posted=1#post689655
 

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Interesting read! I have both copper and aluminum paste but always used the copper on motorcycles and cars leaving the aluminum paste for several bicycle screws. Its obviously a little more complicated than I thought but fortunately I live in a hot dry climate so I don't see much corrosion anyway.

(BTW, I just like the shiny stainless steel, Ti is not appealing to me until I manage to lose 35lbs,...)

thanks!
 

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Thanks.
I will get the most critical bolts (brakes, rotors and forks, shock) and clutch/alternator cover bolts re-plated and use stainless steel fasteners with some anti-seize on other details.
 

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Ive done just this, replaced basically all the bolts with stainless.
I cannot see galvanic corrosion being a real issue with this application, particularly if used with the correct grade of anti-sieze.
Look at what boats use, they use stainless everywhere for bolts and fittings.
 

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Totally Stainlees

There is a auto restoration co in Adams co , Pa that carries a large amount of stainless steel fasteners in SAE and metric .
Been around for a long time
Totally Stainless
1945 Heidlersburg Rd .
Aspers ,Pa

800 767 4781
 

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Corrosion is a galvanic [molecular exchange] reaction. The further apart on the Noble Scale the two metals in contact are, the faster the molecule transfer. warm, moist, polluted, marine air environments combine to enhance the reaction, and don't require any metal-to-metal contact. The air alone does it. 20-gauge hot dipped Galvanized steel will rust through to base metal perforation in less than 12 months near the Port of LA.

Hard Data: https://structx.com/Material_Properties_001.html

Stainless steel [SS] - to - aluminum is a good fit - negligible corrosion risk. The real issue with SS is strength. It has somewhat less strength than steel bolts. Max torque before entering plastic, non-elastic [permanent] deformation and failure of the material is less. Stay with plated steel for mission-critical fasteners.
 

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Some excellent reading from those quotes. Thank you for posting them.
 
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