I was reading the Park Tools website regarding fitting cartridge bottom brackets and came across the following statement -
"Secure removable ring to at least 360 inch pounds using torque wrench. If you are using hand wrench, and are holding the wrench 6 inches from axle, apply 60 pounds of pressure. which is tight. By securing removable ring, you are securing the other side at the same time. Removable ring pushes against fixed flange."
The suggestion being that after screwing the cartridge and adapter by hand it is only necessary to torque the adapter which tightens the cartridge at the same time(presumably because they are opposite threads).
Is this correct? It would be handy if it was since my torque wrench only works for righthand threads but the Shimano instructions suggest that both the cartridge and adapter should be tightened.
Is this correct? It would be handy if it was since my torque wrench only works for righthand threads but the Shimano instructions suggest that both the cartridge and adapter should be tightened.
Ideally, I reckon both sides should be fairly tight but you really don't need a torque wrench for that.
In any case, with cartridge units, quite often you'll find the bearings start to bind before it's as tight as you'd like, probably caused by poor shell facing.
Ideally, I reckon both sides should be fairly tight but you really don't need a torque wrench for that.
I use a 12" stillson with a sutable adapter and pull it up as tight as possible.
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In any case, with cartridge units, quite often you'll find the bearings start to bind before it's as tight as you'd like, probably caused by poor shell facing.
In any case, with cartridge units, quite often you'll find the bearings start to bind before it's as tight as you'd like, probably caused by poor shell facing.
Not in my experience.
I've had bad luck then. Anyone fitting cartridge BB's should tighten a little at a time and keep checking the spindle turns freely, in case they experience the same problem.
I've had bad luck then. Anyone fitting cartridge BB's should tighten a little at a time and keep checking the spindle turns freely, in case they experience the same problem.
I think you may have been unlucky or used a poorly made one. I've fitted 27 this year so far and the only problem has been when I forget to loosen the cable guide screw:-(
Assuming the cartridge unit screws in from the right (i.e. the adapter is on the left) and is of the flanged type:
There is no minimum torque requirement for the right side; just screw it in until the flange is snug against the bottom bracket shell. The left hand side needs to be tightened to the specified torque.
Is this correct? It would be handy if it was since my torque wrench only works for righthand threads but the Shimano instructions suggest that both the cartridge and adapter should be tightened.
Any thoughts? PJay.
I tighten the BB using the fixed ring until it is reasonably tight, actually until it stops but not over tight, then fit the removable one and tighten it until it is reasonably tight, then give it a bit more. Not scientific I know but I don't have a torque wrench. Its all worked so far for me.
I've had bad luck then. Anyone fitting cartridge BB's should tighten a little at a time and keep checking the spindle turns freely, in case they experience the same problem.
I think you may have been unlucky or used a poorly made one.
It was with Campagnolo Mirage & Centaur and Shimano UN73 BBs. These are decent quality jobs, unlikely to be poorly made. I believe the problem is with the bike frames, not the BBs themselves. A side affect of unparellel or uneven shell faces is binding, with cartridge types at least. There may be some other problem with the frames as well that I don't understand.
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I've fitted 27 this year so far and the only problem has been when I forget to loosen the cable guide screw:-(
I'll post the make if anyone is interested.
Yes please, and models. I'd be more interested to know the sort of bikes, though.
My last three problems were with modern road and mountain bikes, that perhaps were not finished properly or were poorly made? One of the exact same BB's that didn't work well in one bike (when fully tightened) worked perfectly well when handed down to my 1980s Raleigh tourer. Fortunately, the BBs in the other bikes that I left a bit loose have not unscrewed themselves. Ideally, I should have the shells faced in case that helps.
