Bicycle Mechanics - How do I change crank bearings?

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lgoodman
05-17-05, 02:20 PM
My crank bearings need replacing on my Scattante Zonal. Can anyone give me some advice on how to do this as I have never done this before. Also, can someone guide me as to what brand of bearings I should replace them with?

Thank you.

Lee

phantomcow2
05-17-05, 02:29 PM
what needs replacing/servicing is the bottom bracket. Usually now bikes come with cartidge bottom brackets so when they wear you just replace them. Some have an integrated BB/spindle in which you may have to buy special cups from the manufacturer. You need to determine what the spline is of your cranks, if you tell us what brand/model your cranks are this will be easier. Its probably Shimano Octalink or ISIS
NzAndy
05-17-05, 02:30 PM
Hi Lee,

I have only changed the bottom bracket on my Giant mountain bike but I'm guessing it may be pretty similar. I bought a special crank puller from the LBS because you really need one to take them off. I also bought a special tool to get the bearing out. Both attach to standard socket sets. If you don't have either of these I would recommend you either buy them or just let the LBS take care of it. Those tools are not expensive and I like to do as much of my own work as I can so I just added them to my collection. I'm sure someone else will have more to add but that is my 2 cents worth.

moxfyre
05-17-05, 02:36 PM
My crank bearings need replacing on my Scattante Zonal. Can anyone give me some advice on how to do this as I have never done this before. Also, can someone guide me as to what brand of bearings I should replace them with?

Thank you.

Lee
The above advice is good if you have a "normal" bottom bracket. However, you may have a crankset with external bearings (at least that's how I've seen this bike sold). Is it a Dura Ace crankset, or a 2005 Ultegra crankset, or some other high-end crankset?

If so, you need a completely different type of bearing cartridge. I've never worked on those. It's a recent innovation and as far as I can tell, every manufacturer of these high-end cranksets uses a slightly different design. Maybe somebody like sydney can tell you the exact details.