Help - chainring bolts

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Mart
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Help - chainring bolts

Post by Mart »

Help - I need some help finding some Single Chainring bolts

MUST be
- Stainless Steel. Cr Moly is just too soft
- Hex on both sides. So I don’t need the separate spanner

Looking to the Boners collective knowledge to find :YMPRAY:
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Bearbonesnorm
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Re: Help - chainring bolts

Post by Bearbonesnorm »

Stainless Steel. Cr Moly is just too soft
Stainless is generally considered a softer material than quality cro-mo steel.
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Mart
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Re: Help - chainring bolts

Post by Mart »

I had some wolftooth ones that were truely awful. Just looked them up actually they were Aluminium
Stripped as I tightened the first one, threw the rest in the bin

Reason I’m asking for Stainless and I was wanting sometjing that won’t strip when I tighten when tightened by my ham fistedness
Will look for Cr Moly too
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Re: Help - chainring bolts

Post by slarge »

Stainless can crack and fail Mart (one reason it's not allowed on suspension bolts on cars), whereas chrmoly will stretch - chromoly steel should be what you want.
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Bearbonesnorm
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Re: Help - chainring bolts

Post by Bearbonesnorm »

Just looked them up actually they were Aluminium
Absolutely no place been a fastener unless it's purely for decoration :wink:
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sean_iow
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Re: Help - chainring bolts

Post by sean_iow »

slarge wrote: Thu Dec 08, 2022 7:49 am Stainless can crack and fail Mart (one reason it's not allowed on suspension bolts on cars), whereas chrmoly will stretch - chromoly steel should be what you want.
Stainless is fine if used in the correct way (grade and size) and are used extensively in the marine industry and in civil engineering when the environmental conditions require it. Advice on reliability from a JLR Engineer :lol: :wink:
Bearbonesnorm wrote: Thu Dec 08, 2022 9:33 am
Just looked them up actually they were Aluminium
Absolutely no place been a fastener unless it's purely for decoration :wink:
The bar clamp bolts on my Hope brake levers are aluminum, never failed. I assume as well as to save weight that in a big crash they would break to save the lever assembly?

Mart, but some stainless ones from Bikemonger

https://www.bikemonger.co.uk/chainset-spares-204-c.asp

I've never had an issue with them. Grease them when you put them in and you can just put your finger on the bask to stop it rotating when doing them up. As they don't corrode you shouldn't need the tool for the back to undo them as well.

The issue with the hex on the back version is that the outer bolt won't screw through rear part so they can bottom out before they are tight, which might have been what happened to your ally ones. I've only seen the hex on the rear on ally bolts, presumably as they are too soft for the shallow slot the normal tool uses. I have used ally bolts with no issues but prefer the stainless or cro-mo.
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Bearbonesnorm
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Re: Help - chainring bolts

Post by Bearbonesnorm »

The bar clamp bolts on my Hope brake levers are aluminum, never failed.
But have you had them crack tested recently? :wink:

You can get high tensile stainless fasteners but they're not commonly available. Most off the shelf will be A2 or A4, go for A4.
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Mart
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Re: Help - chainring bolts

Post by Mart »

sean_iow wrote: Thu Dec 08, 2022 9:49 am
slarge wrote: Thu Dec 08, 2022 7:49 am Stainless can crack and fail Mart (one reason it's not allowed on suspension bolts on cars), whereas chrmoly will stretch - chromoly steel should be what you want.
Stainless is fine if used in the correct way (grade and size) and are used extensively in the marine industry and in civil engineering when the environmental conditions require it. Advice on reliability from a JLR Engineer :lol: :wink:
Bearbonesnorm wrote: Thu Dec 08, 2022 9:33 am
Just looked them up actually they were Aluminium
Absolutely no place been a fastener unless it's purely for decoration :wink:
The bar clamp bolts on my Hope brake levers are aluminum, never failed. I assume as well as to save weight that in a big crash they would break to save the lever assembly?

Mart, but some stainless ones from Bikemonger

https://www.bikemonger.co.uk/chainset-spares-204-c.asp

I've never had an issue with them. Grease them when you put them in and you can just put your finger on the bask to stop it rotating when doing them up. As they don't corrode you shouldn't need the tool for the back to undo them as well.

The issue with the hex on the back version is that the outer bolt won't screw through rear part so they can bottom out before they are tight, which might have been what happened to your ally ones. I've only seen the hex on the rear on ally bolts, presumably as they are too soft for the shallow slot the normal tool uses. I have used ally bolts with no issues but prefer the stainless or cro-mo.

Those bikemonger ones don’t have a hex on both sides, which means I still need the specific tool to tighten. I’ve tried this way and it didn’t work as wasnt tight enough.
The ally ones I had, saw the Allen key strip, don’t think it was bottomed out but just made of cheese
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Mart
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Re: Help - chainring bolts

Post by Mart »

Bearbonesnorm wrote: Thu Dec 08, 2022 9:33 am
Just looked them up actually they were Aluminium
Absolutely no place been a fastener unless it's purely for decoration :wink:
Absolutely agree they were pish. Didnt buy for the bling, bought for the double hex

https://www.wolftoothcomponents.com/pro ... uts-for-1x
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Re: Help - chainring bolts

Post by sean_iow »

Mart wrote: Thu Dec 08, 2022 11:08 am I’ve tried this way and it didn’t work as wasnt tight enough.
How tight do you want them :o I can do mine up with just turning the outer part until I cant get them any tighter, the friction of the rear bit in the hole stops it turning. This is probably way too tight, from a quick search

A Shimano "General Operations" manual states the tightening torque for road chainwheels is 12-14 N-m. For mountain bike chainwheels it's upped to 14-16 N-m for large and middle ring and 16-17 N-m for the smallest ring of a triple

Or just buy the proper tool for the back

https://www.bikemonger.co.uk/var-chainr ... 2173-p.asp
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Mart
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Re: Help - chainring bolts

Post by Mart »

Thanks Sean. Would like to have them tight enough that the back bit doesn’t turn and they stay put.

I’ve got one of the those tools thanks but would like to leave it at home when on trips.
As I already have hex’s on the mult tool I would prefer to just use those if possible.
Hence why I was asking about double hex front and back.
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Re: Help - chainring bolts

Post by sean_iow »

Hi Mart

I've never seen steel or stainless bolts with the hex both sides and a look on the web didn't find any. I think they use the hex at the back on ally bolts.

Do the keys come off your multi-tool you carry? Mine only unfold, so unless I carry 2 I wouldn't be able to hold/turn both sides at once anyway. I've also never had to remove a chaining bolt, or tighten one up, other than in the shed when swapping chainrings.

I do carry a spare chanriing bolt and I have had to use it.... as a caliper spacer on the HT550 when I lost a bolt out of it and snapped the adapter. Luckily it was the sort with the slots and I used the back part as the M6 caliper bolt (borrowed from my stem topcap) wouldn't fir through the hex.#

Edit, I've been looking on the SJS website, but not all of them have the rear of the bolt pictured. Might be worth contacting them, if anyone is going to have some it will be SJS.
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Lazarus
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Re: Help - chainring bolts

Post by Lazarus »

I also looked a while back and found none, except the alloy ones you cannot tighten enough.

Also never needed to do a trail side repair on a chainring ( though did once lose one bolt on a ride and now carry a spare I have yet to use.)
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Re: Help - chainring bolts

Post by sean_iow »

Found some :grin: but they are for doubles :sad:

https://www.sjscycles.co.uk/chainsets/t ... pack-of-5/

You could shorten them if to long or put a chainring spacer under the head.
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Re: Help - chainring bolts

Post by stevenshand »

Chainring Bolt Bingo : http://www.diacompe.com.tw/product/torx-bolt-nut/

Torx, aluminium and different colours.

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