https://www.pedalconsumption.com/file..._crankset.html

4 bolt?

That does look a little weird, huh?

There's probably one under the arm. I've seen some cranks like that. Terrible design.

the 5th bolt probably threads into the back of the arm. a la campagnolo. record cranks have been like this for years with no ill effects that i know of. i hear its lighter and stiffer, what i do know is it looks nice.

Ritchey and Zipp(4 bolt)have that design also.

i think the late 90s early 2000 specialized cranks were this way too

edit: i lied, strongarms were standard 4 bolt

I'd have to assume there is a 5th bolt as otherwise it'd have to be an extremely bizarre proprietary ring design that wouldn't make a ton of sense. Having the bolt behind the arm is a bit of a pain in the ass but no big deal IMO

you dont need a proprietary ring...

the bolt is long and threads into the crank from the back and there is a spacer between the chainring and crank. its not rocket science, or new technology.

whats a pain about it? its just one chainring bolt that doesn't require a nut or any tool to hold it...

edit:

early campy cranks with the hidden bolt did have a "half spider arm" behind the crank and the nut was pressed into the large chainring. this did use a special chainring but you could use a standard chainring and nut if you wanted to. (ive done it)

You misunderstood me.

If this ring was a 4 bolt, and in the pattern pictured, it would be a proprietary ring, as that would make it different than the current 4 bolt pattern in use.

As for being a pain, I thought I recalled trying to get at the bolt of a regular chainring that happened to have the crank arm in the way before, however upon looking at the bike in question I was mistaken. It wasn't behind the crank arm at all, just a pain in the ass because the thickness of the crank arm at the spider made it awkward. For some reason I thought it was completely behind the crank arm.

oops, that i did. my apologies sir.

OK, but it still looks odd to me. It just feels like it's missing something.

it looks different, I guess that's enough.

or maybe its just the same

not missing, just hidden.

I get that, but the look of it makes me feel like a gap has to be filled. I'm just being stupid

I want one for sure.

centering the chainring is a little harder using the hidden 5th crank arm like this. atleast it was when I converted my campi record crank arms to single ring and used a Miche primato 135bcd chainring.thats the only draw back I ever had with this design. i think it looks rad!

man those look sick! im looking for a new crankset too, might have to check these out.

They've been making these for road bikes for years as the Superbe and Superbe Comp. They do look quite nice, in a Campag Chorus-a-like way.

chorus had a traditional 5 arm spider until 10spd, record has been this style since 8spd, maybe longer...

i'm glad there are other fans!!

alloy

well what do you know. my alloy chorus 10v cranks (and every one ive ever seen) has 5 spider arms.

either way, im pretty sure they started it with record 8v and chorus did not get it till later 10v

edit:
from what i can tell that crank was the 2006, the last year for square taper

4 bolt isn't exactly proprietary unless we are talking about 960 series shimano xtr. Despite the 960 xtr, all 4 bolt patterns are 104mm.

This thread is giving me a serious Campagnolo jones. Now to figure out how to get my hands on a group set and turn my conversion into some sort of fixed gear conversion that has freewheel capabilities and multiple gears.