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• #2
and...
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• #3
Doesn't look right... sure your cranks are JIS? If you want I have a brand new in box Shimano UN55 JIS 110 mm that I no longer need
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• #4
The cranks are NJS DA 7600 so by all acounts they are definitely ISO.
But thanks anyway...
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• #5
ISO cranks on JIS BB, it looks like.
http://sheldonbrown.com/bbtaper.html
You might also want to measure the distance between the chainring and the BB face to check you're getting the chain line you're expecting.
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• #6
I have 2 pairs of DA 7600s on JIS bbs and they look a lot better than that.
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• #7
Yeah, Token BBs aren't a true ISO taper, I had the same issue with my 75s.
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• #8
The truth is that most tapers are so roughly made that they don't satisfy ISO or JIS specs. FAG did a report on this. I'll try and find it. You've got to love those Germans.
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• #9
Oh dear... Did you get your money back?
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• #10
That would be interesting thanks. Maybe I'll just ask for a replacement, or a campy one that might be better made?
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• #11
No, just sold it on at a loss. Campag works spot on.
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• #12
I was under the impression all Shimano cranks were JIS
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• #13
NJS cranks are all ISO, no?
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• #14
Yeah NJS are ISO. Plus if the cranks were JIS and the BB was ISO I think the crank would bottom out on the spindle rather than sit too far out on it.
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• #15
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• #16
Funnily enough I was looking at 3 bottom brackets today to try and work out what was going on. An NJS Hatta, the Token ISO one mentioned above and un55. The token and UN55 were close enough in taper length that I couldn't tell the difference, but the NJS one was definitely shorter than the other two, maybe only by 1 or 1.5 mm though.
Sheldon also mentioned that the end of an ISO tapers to a slightly narrower end, but if it does it isn't by an amount discernible by my eye when placing them against each other.
Anyway, the bottom line is I still don't get why the crank wouldn't go on to the Token ISO BB, other than it might just be poorly machined. I would try the cranks on the NJS BB but the drive side cup is stuck in another frame at the moment...
Thanks for the help anyway guys.
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• #17
I'm struggling with the new forum's search function, but if you trawl Tester's posts he does go into more detail (search: tester/sheldon/taper).
My understanding is that JIS are measured up to the 1mm chamfer, where as ISO are end-to-end, hence the 2mm difference; ie 109mm JIS = 111mm ISO.
So I've got some NJS cranks, which are by all accounts ISO, I bought a 111mm ISO BB made my Token, and tightened it up as much as I could by hand with a tool about 8-10" long, its very tight and it feels like it won't on on any further, but it looks like the pic below, not right...
I have tightened quite a few cranks onto bottom brackets before and not had an issue, but this does not look right. I have a torque wrench on the way, just waiting for the shop to get it in stock, but honestly I don't think its an issue with it needing tightened more as it doesn't even look close to seating on the tapers properly.
Have they sent me a JIS bottom bracket instead or something?!
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