I have this bottom bracket on my belt drive bicycle.
Shimano UN300 68 UJ BC137x24 D-EL
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The person who sold me the bike said the BB's length is 127mm, width 68mm, and square type. (I cannot get hold of the seller because he is in a far away country.)
When I went to a bicycle shop, they showed me a replacement. It was non-Shimano and printed on the BB was 127.5mm. (I forgot to take a picture :( )
I looked on Shimanos website and 2 random online shops.
Shimano and one of the shops have 127mm. The other site has 127.5mm
Random shop 1https://www.rosebikes.de/shimano-bb-un300-bsa-68-vierkant-innenlager-2688343
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Shimanohttps://bike.shimano.com/en-US/product/component/tourney-tz500/BB-UN300.html
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Random shop 2 -> 127.5mm (and it has the D-EL code)https://www.bike24.com/p2372410.html
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Question
- Is 127mm = 127.5mm, i.e. are these one and the same part and some people are just lazy and leaving out the .5mm?
- OR Are there 2 BBs, the one is 127mm and the other is 127.5mm? And only 127mm will be the correct match for my belt drive?
