Is this an inner or outer chainring?

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UpWrong
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Is this an inner or outer chainring?

Post by UpWrong »

46T. Is this an inner one or an outer ring?
IMG_20210421_132109_HDR.jpg
IMG_20210421_132036_HDR.jpg
High res photos here https://photos.app.goo.gl/KL5coJ4ML6k3kT6v8
gregoryoftours
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Re: Is this an inner or outer chainring?

Post by gregoryoftours »

Outer. An inner isn't ramped and pinned unless it's the middle of a triple, and the seating for the head of the chainring bolt is also on the outer side of the chainring. The threaded holes are to screw a peg into depending on your crank spider configuration, to prevent the chain from jamming in between the outer chainring and the crank arm.
Last edited by gregoryoftours on 21 Apr 2021, 6:56pm, edited 2 times in total.
markjohnobrien
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Re: Is this an inner or outer chainring?

Post by markjohnobrien »

UpWrong wrote: 21 Apr 2021, 6:43pm 46T. Is this an inner one or an outer ring?
IMG_20210421_132109_HDR.jpg
IMG_20210421_132036_HDR.jpg

High res photos here https://photos.app.goo.gl/KL5coJ4ML6k3kT6v8
Looks like outer to me.
Raleigh Randonneur 708 (Magura hydraulic brakes); Blue Raleigh Randonneur 708 dynamo; Pearson Compass 631 tourer; Dawes One Down 631 dynamo winter bike;Raleigh Travelogue 708 tourer dynamo; Kona Sutra; Trek 920 disc Sram Force.
markjohnobrien
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Re: Is this an inner or outer chainring?

Post by markjohnobrien »

gregoryoftours wrote: 21 Apr 2021, 6:52pm Outer. An inner isn't ramped and pinned unless it's the middle of a triple.
It would be a big and peculiar triple if it was the middle ring!
Raleigh Randonneur 708 (Magura hydraulic brakes); Blue Raleigh Randonneur 708 dynamo; Pearson Compass 631 tourer; Dawes One Down 631 dynamo winter bike;Raleigh Travelogue 708 tourer dynamo; Kona Sutra; Trek 920 disc Sram Force.
UpWrong
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Re: Is this an inner or outer chainring?

Post by UpWrong »

gregoryoftours wrote: 21 Apr 2021, 6:52pm Outer. An inner isn't ramped and pinned unless it's the middle of a triple, and the seating for the head of the chainring bolt is also on the outer side of the chainring. The threaded holes are to screw a peg into depending on your crank spider configuration, to prevent the chain from jamming in between the outer chainring and the crank arm.
Thanks. That's what I thought. I bought it from Spa as the middle in a super compact double, so a triple with a chain guard as the outer. Looks like they sent me an outer ring by mistake
Steve
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Re: Is this an inner or outer chainring?

Post by Steve »

UpWrong wrote: 21 Apr 2021, 7:07pm
gregoryoftours wrote: 21 Apr 2021, 6:52pm Outer. An inner isn't ramped and pinned unless it's the middle of a triple, and the seating for the head of the chainring bolt is also on the outer side of the chainring. The threaded holes are to screw a peg into depending on your crank spider configuration, to prevent the chain from jamming in between the outer chainring and the crank arm.
Thanks. That's what I thought. I bought it from Spa as the middle in a super compact double, so a triple with a chain guard as the outer. Looks like they sent me an outer ring by mistake
I think you'll find it wasn't a mistake, as far as I can see it is what you need for that set-up. Why do you think it would be wrong for the job?
UpWrong
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Re: Is this an inner or outer chainring?

Post by UpWrong »

Because it has to bolt to the inner face of the spider so the ramps and pins will be on the wrong side to lift the chain from the granny ring.
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andrew_s
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Re: Is this an inner or outer chainring?

Post by andrew_s »

It would have to bolt on in the normal orientation, with the lettering on the outside and the ramps & pins being correct.
What would be wrong are the recesses for the bolt heads
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horizon
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Re: Is this an inner or outer chainring?

Post by horizon »

From Spa website:
Super compact double chainset created by replacing the outer ring of a triple with an aluminium chainguard
Zicral rings are CNC machined 7075 T6 with black or silver anodization and laser engraving. Outer rings are ramped and pinned for smoother shifting. 7,8,9,10 and 11spd compatible.
I have the 42T version but having looked I cannot tell the difference between mine and the OP's, but that is possibly as much to do with lack of expertise as anything.
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
UpWrong
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Re: Is this an inner or outer chainring?

Post by UpWrong »

I have emailed Spa with the photos and asked. Waiting on a reply.
gregoryoftours
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Re: Is this an inner or outer chainring?

Post by gregoryoftours »

Steve wrote: 21 Apr 2021, 8:26pm I think you'll find it wasn't a mistake, as far as I can see it is what you need for that set-up. Why do you think it would be wrong for the job?
Used in the middle ring position on a triple crank, with a chainring guard in the normal big ring position would work as long as the chainring bolts are long enough, but it's a bit of a bodge. The backs of the chainring bolts won't be recessed into the chainring because the recesses are cut on the other side for use as an outer chainring, which is what it is.

Looking at the spa site maybe it is just a standard outer chainring they bolt to the inside of the spider, although I'd be surprised because I would have thought the chain might catch on the backs of the un-recessed bolts when in the small ring.
NickJP
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Re: Is this an inner or outer chainring?

Post by NickJP »

I have several cranks setup this way (triples setup as a double with a chain guard in the outer position, and the "big" chainring is always one intended as a middle chainring. Otherwise, the chainring bolts aren't recessed into the back of the chainring, and can catch the chain when using the small ring on anything except the two or three biggest cogs.

Sugino sell "middle" ramped/pinned chainrings up to 48t, for use on their 110/74 OX series double cranksets.
Steve
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Re: Is this an inner or outer chainring?

Post by Steve »

Now I see the problem. Also that Spa do list 46T available as a middle ring, which is obviously what the OP had ordered. I hadn't realised middle rings were made so big.
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531colin
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Re: Is this an inner or outer chainring?

Post by 531colin »

And the correct answer is; it needs to be a middle chainring, because it fits to the inside of the spider, so the bolt recesses need to be on the granny ring side, otherwise the chain on the granny ring will foul the bolt heads.
ALSO if its a Sugino/Stronglight/Spa crank which needs the pesky washers, it still needs them when set up as a 2 chainrings from 3.... otherwise the chain will drop down the gap between the 2 rings. (and may foul on the chainguard)
markjohnobrien
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Re: Is this an inner or outer chainring?

Post by markjohnobrien »

Steve wrote: 22 Apr 2021, 7:50am Now I see the problem. Also that Spa do list 46T available as a middle ring, which is obviously what the OP had ordered. I hadn't realised middle rings were made so big.
Same for me: I’ve never seen or used a middle ring that big. Outer, yes, but not middle.
Raleigh Randonneur 708 (Magura hydraulic brakes); Blue Raleigh Randonneur 708 dynamo; Pearson Compass 631 tourer; Dawes One Down 631 dynamo winter bike;Raleigh Travelogue 708 tourer dynamo; Kona Sutra; Trek 920 disc Sram Force.
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