BB bearings...
#1
Thread Starter
McNightrider
Joined: Mar 2007
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BB bearings...
My bb is having some play and not running as smooth as before. So time to replace some new bearings, it is a sugino 75 BB. I cannot get my head on some original sugino75 bearings since I locate in Aussie.
Does anyone know what bearing do they run? And would those PW one fits in them??
Cheer,
Dub.
Does anyone know what bearing do they run? And would those PW one fits in them??
Cheer,
Dub.
#6
THIS SPACE FOR RENT
Joined: Jan 2006
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Bearing retainers are considered uncool because lots of low end bikes had them for manufacturing ease, but especially in a 75 bb I don't think they're a problem. They make it a lot easier to service the bottom bracket, and while one extra ball is theoretically slightly better, it doesn't really work that way in practice and even the theoretical gains are minuscule. If you need to replace the bearings you just poke out the old ones with some small tool or your bare hands and put in new 1/4" bearings.
However, if your BB had play in it, you don't need new bearings, you need to learn to adjust your BB, as it's probably simply loose. If achieving a proper adjustment is impossible, then the bearings may be at fault, though it's more likely that the cups are worn than the bearings. Replacing the bearings would be more something you'd do during periodic maintenance. Also, replacing the bearings in free ball setups is really something people do more because it's cheap and easy than because it's really all that necessary.
However, if your BB had play in it, you don't need new bearings, you need to learn to adjust your BB, as it's probably simply loose. If achieving a proper adjustment is impossible, then the bearings may be at fault, though it's more likely that the cups are worn than the bearings. Replacing the bearings would be more something you'd do during periodic maintenance. Also, replacing the bearings in free ball setups is really something people do more because it's cheap and easy than because it's really all that necessary.
#8
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The retainer is wonky? If it's bent a little , just bend it back, they don't have to be awesomely perfect, the bearings just have to be able to be in plane with one another without it getting in the way. If it's gummed up, soak it in mineral spirits or gas or kerosene or whatever overnight, air dry it, and regrease.
If you've taken it out it's also possible it's in there backwards, which will feel super wonky and may have bent it. In the pic above the side that is down on the one in the bottom middle is the inside, i.e. it should be against the spindle. If you mess with the parts loose in your hands for like 10 seconds it's obvious how it goes together, but when everything is all greasy it's easy to screw up.
You can pack it without retainers and it will be fine, just lay in a bead of grease, put in the bearings one by one, and lay a bead of grease over that. Grease is gooey enough that they won't fall out if you're careful about putting the spindle in straight. You will be able to fit an extra one in there, but I wouldn't necessarily do it. Putting in an extra bearing makes the bearings run on a slightly different part of the spindle and cups, which means that instead of the nice beautiful race that your bearings should have polished for you, you're out on fresh metal that is rough by comparison even fresh from the factory. Not a huge deal, especially with a BB that nice, the point being more that you don't have to put another one in. If you do go that route, use all new balls and be sure to get grade 25 (not grade 300, which is worse).
If you've taken it out it's also possible it's in there backwards, which will feel super wonky and may have bent it. In the pic above the side that is down on the one in the bottom middle is the inside, i.e. it should be against the spindle. If you mess with the parts loose in your hands for like 10 seconds it's obvious how it goes together, but when everything is all greasy it's easy to screw up.
You can pack it without retainers and it will be fine, just lay in a bead of grease, put in the bearings one by one, and lay a bead of grease over that. Grease is gooey enough that they won't fall out if you're careful about putting the spindle in straight. You will be able to fit an extra one in there, but I wouldn't necessarily do it. Putting in an extra bearing makes the bearings run on a slightly different part of the spindle and cups, which means that instead of the nice beautiful race that your bearings should have polished for you, you're out on fresh metal that is rough by comparison even fresh from the factory. Not a huge deal, especially with a BB that nice, the point being more that you don't have to put another one in. If you do go that route, use all new balls and be sure to get grade 25 (not grade 300, which is worse).




