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PostPosted: Tue Nov 24, 2020 9:09 pm 
Old School Grand Master

Joined: Tue Oct 09, 2007 1:55 pm
Posts: 10506
Location: New Forest, UK
legrandefromage wrote:
Not a clue! Cranks were bendy, frame was small, sold it


And there I was worrying if you had sold the Norman Fay!

Thanks, I'll see what M737 with a short BB feels like.


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PostPosted: Tue Nov 24, 2020 9:13 pm 
King of the Skip Monkeys
King of the Skip Monkeys

Joined: Wed Nov 07, 2007 4:34 pm
Posts: 33216
hamster wrote:
legrandefromage wrote:
Not a clue! Cranks were bendy, frame was small, sold it


And there I was worrying if you had sold the Norman Fay!

Thanks, I'll see what M737 with a short BB feels like.



Kermitgreenkona has the Norman, it will end up with me again soon, I'm sure.


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PostPosted: Tue Jan 12, 2021 8:20 pm 
Dirt Disciple

Joined: Tue Jul 14, 2020 6:44 am
Posts: 85
So would a TA/ Stronglight be a lot more flexy than an hollow tech?


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PostPosted: Tue Jan 12, 2021 9:23 pm 
Old School Grand Master

Joined: Tue Oct 09, 2007 1:55 pm
Posts: 10506
Location: New Forest, UK
A lot of this is Shimano marketing puff, as there is no energy loss in the crank from flexing - it simply springs back. The deflections are relatively small anyway, cartianly by comparison with bottom bracket flex.

When the bike industry went to aluminium frames (because they were cheaper to make than steel) then they were noticeably stiffer and harsher to ride. 'Not harsh sir, stiff! Low energy loss!' And thus the myth was born. As Cycle journalism generally doesn't dare moon the Shimano gorilla, this stuff doesn't get challenged. For some reason the magazine that did real-life tests on a jig and worked out that the latest Dura Ace shifted more slowly than the old one didn't get many more reviews to do. Etc.
If you read the Bicycling Science book, US Army research suggests that harsh frames would be actually less efficient as they bounce the muscles around which DOES give an energy loss.


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PostPosted: Tue Jan 12, 2021 10:56 pm 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
Posts: 2887
Tommy27 wrote:
So would a TA/ Stronglight be a lot more flexy than an hollow tech?

All you can be sure of is that you won't notice whether it is or isnt, and any difference in speed will be microscopic

It will weigh a few grammes more if that matters


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PostPosted: Mon Jan 18, 2021 10:15 am 
Dirt Disciple

Joined: Tue Jul 14, 2020 6:44 am
Posts: 85
I think what attracts me to going back to square taper is that in 7 years, I've had 3 hollowtech bottom brackets and 2 pairs of cranks. I don't remember ever having to change them so much beforehand?


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PostPosted: Wed Jan 27, 2021 8:22 pm 
Dirt Disciple

Joined: Tue Jul 14, 2020 6:44 am
Posts: 85
Going to put something up in the wanted section, any suggestions for what would be best to run a 46/ 30 on?


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PostPosted: Wed Jan 27, 2021 9:26 pm 
Old School Grand Master
User avatar

Joined: Fri Dec 10, 2010 10:40 pm
Posts: 4955
Location: The Royal Society of Insobriety
Either a compact MTB triple (94 BCD) without an inner ring (Ritchey for instance, good luck!) or a Stronglight pattern chainset with 86 BCD spider - these are super versatile as you can run any combination of rings from 28 tooth upwards, as close or far away as you think you can get away with, single, double or triple. And the Q factor isn't that bad on the later ones.

I'm planning on fitting a Ritchey triple 110 on my 11 speed road bike once I have rebuilt it, I understand it works well and as there are no tabs for the granny ring the recommended BB length is low - 103 ish - and you can get a 33 tooth small 110 BCD ring too.


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 Post subject: Re:
PostPosted: Sun Jan 31, 2021 4:06 pm 
Dirt Disciple

Joined: Tue Jul 14, 2020 6:44 am
Posts: 85
Not actually considering these seriously yet, because as much as I love my Roberts frame I'm trying to save for the next one and I'm more intrested in trying this to see how it feels before investing in my 'dream' 650b bike.

However these would be within budget
Image
https://www.veloduo.co.uk/collections/s ... kset-mk-ii

Image
https://www.veloduo.co.uk/collections/s ... e-chainset

These wouldn't
Image
https://www.svencycles.co.uk/rene-herse ... ble-cranks

These might, but only seem to be 170 and I prefer 165
Image
https://www.velovitality.co.uk/collecti ... e-chainset


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PostPosted: Sun Jan 31, 2021 4:25 pm 
Dirt Disciple

Joined: Tue Jul 14, 2020 6:44 am
Posts: 85
Is there any particular advantage to having the very small bcd with the rings bolted so directly?


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