Bicycle Mechanics - BB Question: Non-drive side BB cup not tight against shell - OK?

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wildturkey
11-17-07, 02:01 PM
I just posted this in the SSFG forum since the bike in question is a fixed gear, but then I realized I should probably be asking some "real" mechanics the question :)...
Anyway, I had a shop replace my cartridge bottom bracket (IRD QB-75 to go with my Sugino RD2 cranks). I realized when I got home that a full thread of the non-drive cup (left side) was showing -- sticking out slightly (2 mm) out of the BB shell. I don't have a crank removal or BB tool to take off the cranks and test if the cup is tight. Is this something I should bother going by the shop to ask about? Or, is it normal for the BB cup to not be totally tightened against the shell (so that a thread shows)? Thanks for the help!

vpiuva
11-17-07, 02:41 PM
I would assume the shop torqued/tightened it properly and that's the threads they were left with. Should be no issue but if it will make you feel better call the shop and ask the mechanic that installed it. At least that way they are forewarned if it does come loose on you. If it does loosen while you're riding the crank won't fall off, you'll just have to ride home slower
wildturkey
11-17-07, 03:22 PM
Good idea... thanks vpiuva

kenshinvt
11-17-07, 04:38 PM
also, after you go for a good ride on it, try grabbing both crank arms and push/pull to see if you can rock them back and forth to find any play in it.
dobber
11-17-07, 08:36 PM
The non-drive side cup (assuming we're talking about a cartridge type bb here) has a wedge shape to it and will only go in so far. Forcing it in further will either pinch the bearings or crack the cup.
supcom
11-18-07, 08:41 AM
I just posted this in the SSFG forum since the bike in question is a fixed gear, but then I realized I should probably be asking some "real" mechanics the question :)...
Anyway, I had a shop replace my cartridge bottom bracket (IRD QB-75 to go with my Sugino RD2 cranks). I realized when I got home that a full thread of the non-drive cup (left side) was showing -- sticking out slightly (2 mm) out of the BB shell. I don't have a crank removal or BB tool to take off the cranks and test if the cup is tight. Is this something I should bother going by the shop to ask about? Or, is it normal for the BB cup to not be totally tightened against the shell (so that a thread shows)? Thanks for the help!

Perfectly normal.
wildturkey
11-18-07, 09:46 AM
Thanks everyone!