Flange bolts - where to buy?

[Ixion]

Yes. Heat cycling. That's what I was thinking of, not expansion rate.

[psyguy]

Flange bolts? Sounds familiar, but what do you need them for (what application)?

all the bolts on my engine are flange bolts (except for the side covers), and stainless -it's a 1980 gs 850 (that i'm rebuilding in another threadhere)
i snapped a few trying to correctly torque them and thought i should replace them with the same type bolt

[psyguy]

Aren't flange bolts bolts with a flange built into the head (like an in-built washer)? Used for things like bolting brake discs to wheels.

yup, that's what i'm after, bolts like on your photo, that are wider at the head base, all the bolts on my engine are like that (the gs850 that's appart, in another thread here), and also the nuts that hold down the block and the head

sorry if that wasn't clear from the beggining, i thought that's what a flange bolt meant and didn't know there were other meanings

why stainless? because that's what the originals seem to be. not?
a few of the nuts were replaced with ordinary steel nuts and rusted so much that i ended up undoing the whole head-holding-down stud before being able to remove the nut from the stud...

[Ixion]

Doubt that head retaining bolts would be bog 316 stainless. They're usually a very specific grade of steel, designed to stretch just the right amount under the specified torque. Not quite as specific as bigend bolts, but getting up there. I'd be very hesitant to replace top end retaining bolts or studs with anything other than the kosher article. If I had to cos the genuine thing wasn't available, I'd got for a high tensile steel item, and if necessary use a separate washer.

[psyguy]

Doubt that head retaining bolts would be bog 316 stainless. They're usually a very specific grade of steel, designed to stretch just the right amount under the specified torque. Not quite as specific as bigend bolts, but getting up there. I'd be very hesitant to replace top end retaining bolts or studs with anything other than the kosher article. If I had to cos the genuine thing wasn't available, I'd got for a high tensile steel item, and if necessary use a separate washer.

cheers. i'm not saying it's 316 but it looks like stainless and definitely doesn't rust (and my knowledge is really limited here)
anyhow, do you know where i can find M10 fine thread high tensile nuts?

[Ixion]

Hm. The Suzuki parts fiche appears to show ordinary long studs from crankcase throuh the barrel and head, with a washer and nut on the top. Usual stuff. Nuts studs and washers still available ex Suzuki, nuts about 2 bucks US studs 3 or 4 bucks. Reckon if you talked nicely to the guys at Colemans they'd order them for you.

Maybe some previous owner tried to get pretty ?

EDIT: there's what looks like a dome head nut and washer on the outside studs, still listed about $5US. And a couple of smaller bolts that go somewhere , also still listed.

[Motu]

Japanese M10 theads aren't ISO,they will need to be sourced OE.I have so many nuts and bolts salesmen come in and say they can do any metric bolt there is.So I hand them any randomly picked Japanese M10 bolt - ''NO problem Sir,we have plenty of those!''.They don't bother to come back,but just ring up saying they can't do them.Go to PickApart and scrounge around,or change tack - cadnium plate steel nuts and bolts,it's fairly cheap.

[Max Preload]

Here's a good list of finishes that I use for reference.

http://www.allmetalcorp.com/htm/pg8_6_00.htm

[pete376403]

GS head nuts will be steel (probably grade 8 or better but steel) the acorn nuts are chromed, noit stainless.
The factory service manual has a table of all the nuts and bolts and their material or grade, I could post this info if required (don't know if the Clymer or Haynes manuals will have this)

[Madness]

Japanese M10 theads aren't ISO,they will need to be sourced OE.

I've struck a few Suzuki OEM fasteners that don't match any standard thread form. I've often thought it's the Japs way at getting back at the west for the war. The Eyeties are pretty good at it too, although they take a different tack and use ISO standard M7 & M11, just for a laugh!

[psyguy]

GS head nuts will be steel (probably grade 8 or better but steel) the acorn nuts are chromed, noit stainless.
The factory service manual has a table of all the nuts and bolts and their material or grade, I could post this info if required (don't know if the Clymer or Haynes manuals will have this)

mate, that would be great, my haynes manual doesn't have it

[psyguy]

Here's a good list of finishes that I use for reference.

http://www.allmetalcorp.com/htm/pg8_6_00.htm

very informative, thank you

[Max Preload]

Unfortunately being the shithole backwater NZ is, most of them will not be available retail but even if they are you'll actually struggle to find out which ones any particular company can supply as the counter staff aren't the most informative, and the reps aren't much better.

[Max Preload]

I've struck a few Suzuki OEM fasteners that don't match any standard thread form. I've often thought it's the Japs way at getting back at the west for the war. The Eyeties are pretty good at it too, although they take a different tack and use ISO standard M7 & M11, just for a laugh!

In what way are they not ISO/DIN compliant? I don't think there is a JIS standard for fasteners. The 'eyeties' would be DIN for sure.

Here's one I use for thread reference:
http://www.gewinde-normen.de/en/index.html

[Madness]

In what way are they not ISO/DIN compliant?

I've struck a few OEM threads on Suzuki's (in a previous sales role) where the pitch was far finer than ISO fine pitch, can't remember any specific details but a sump-plug comes to mind that was something like M14 x 0.75. Weird shit like that would crop up from time to time, always fun trying to explain to customers that they couldn't buy what was required.