The cinelli alter stem I have is 26.4 afaik. La croix shim to the rescue.
what flavor though? might be the only valid use for a coconut
The best, pampelmouse, however it’s spelled.
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what is the SI/ISO rule that Italy followed for rounding when 1.25" = 31.75mm… ASTM E29 is ‘five-even’ and ASTM D6026 follows the ‘round-up’ rule.
hmmm. never knew about “five even”… and 5/4” is exactly 31.75mm (in math, but not manufacture i’m sure). does the even unit become the mm or the tenth of an mm? either way it would seem to lend itself to rounding up in this case, says this nerd who doesn’t actually know what he’s talking about WRT any astm anything
Cinellli and 3TTT
Shop here had some Cinelli bars from around when they could have been either 26.4 OR 26.0, so I asked…
Owner was convinced that 26.4 was my imagination and busted out his Verniers, saw it was something .4 and goes “see, 25.4mm.” Even when I pointed out that his calipers showed 26.4 he wasn’t swayed…
Is this a kind of lost knowledge?
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Deda used to list their pre-oversized road bars and stems as 25.8mm, but perfectly compatible with everyone else’s 26.0. They’ve always been dicks about rounding.
There are also a lot of earlier French 25.0mm handlebars and stems of all types, I think this was the most justified of metric roundings and the least used, much like the french tire sizing system.
How Cinelli got to 26.4 is the real mystery.
Can’t leave out Deda’s 31.7mm handlebars
we (i.e. blakey) already covered the astm standards that maybe could have gotten them there, but still seem a bit off
Hilariously enough, at Recycled there are sets of Deda handlebars with paint pen WARNINGS ABOUT ONLY WORKING WITH 31.7 STEMS!!!
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Lol. I remember seeing that. Obviously had some issues in the past.
I just accidentallied a 90mm Ritchey WCS stem that fits 31.8 steerers. Shitty way to find out that such a thing exists. Must… leave… cave… occasionally…
I have ~10,000m on some 31.7 Deda Deeps with a 31.8 stem and I still have all my teeth
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thatsthejoke.jpg
If I recall the standard measurement is 31.75 but Deda rounds down and everyone else rounds up.
it’s 31.75 because it’s just 1 ⅛" converted to metric.
ordering bike tubing is maddening because it’s all actually in inch fractional diameters but everything is listed in crazy metric. Until you get real fat then it’s just metric.
5/4”, not 9/8”
not into pedantry that hard, just wanted to write out 5/4”
Keep this going. What’s the best shim for 25.4 to 26.4? Does a more expensive drink equal a better shim?
Isn’t this a chapter in Zen and the art of motorcycle maintenance?
I think it’s just a matter of personal preference, like coke v Pepsi.