BB sealed unit, can I assume a Shimano UN55 will fit?

[Luegolover]

Hello,

My wife's Charge Plug is about 4 years old and I have noticed that the sealed BB is grinding a little. I looked on the Charge web site but it is not clear exactly what type of BB would have been fitted. It is a square taper unit so can I assume that the Shimano UN55 is likely to be a suitable replacement?

Also, are the universal Topeak crank puller

http://www.evanscycles.com/products/topeak/universal-crank-puller-ec049323

and the FWE Shimano/ISIS cartridge tool

http://www.evanscycles.com/products/fwe/shimano-isis-cartridge-bb-tool-ec053199

Will both be suitable for doing the job?

Cheers
Steve

 

[stumpy66]

Hi the crank puller looks fine, I'd get this bb tool instead http://www.evanscycles.com/products/park/bbt2-shimano-bottom-bracket-tool-ec005486

The bb size will depend on the axle length, best thing to do is to check the size which should be printed on the Bb shell.

Unless another charge plug owner can advise on the proper size

 

[Luegolover]

Thanks for that. I think I have established that the axel length is 103 which means I can't go for a UN55. I don't want the bike off the road for long as it is used for commuting so I may just buy one from Evans and hope it is correct and return it if not.

OK, I am curious as to why you recommended the park BB tool, very happy to take your recommendation but just wondered what is behind it?

Cheers
Steve

 

[Sharky]

Even though I can and have changed many BB's, if it's a one-off job like this, it might be better to just take it to the LBS. They will have a shelf full of BB's and will fit the right one. Did this with my local BB and the all in cost was around £30, including the new BB.

 

[Gravity Aided]

You'll need to measure your bottom bracket shell, and spindle length. I use a digital micrometer to do this, so I get metric. All lengths are in millimeters. Measure BB shell without cups, and, if it is a threaded spindle, measure the length without the area of the threads included. Park BB tool is an excellent tool, and it fits socket tools and wrenches, and puts up with a lot of ham fistedness. I think I am ham fisted at times, and a test for any tool.