Upgrading a Bottom bracket.

[Mussels]

I have what appears to be a 3 piece bottom bracket as I have deduced in the Wisper clinic. As I don't want to spend hours learning a new skill I would like to swap it for a sealed cartridge BB but the internet is confusing me.
There are so many different sizes and thread types and all I have to go on is "BSA 1.37" x 24T R/L", can anyone tell me how easy this is to upgrade to a widely used standard which is easy to service/swap and doesn't cost the earth.
I fully expect I need to change the cranks as well so I'm ready for that cost too.

 

[Lloyd_50cycles]

There are 2 figures given on a Shimano Bottom bracket. The shell width and axle length. Axle length is easy, but beware if there is a tread sticking out of the end of the axle not to include that in the measurement. You measure from the tip of the square taper on one side to the tip on the other. It should give you a measurement between 110mm and 127mm ish. This is very approximate, and a lot of E bikes run larger than normal axles to cope with the extra sensors etc.

The secont measurement is the shell width. This is the measurement of your frame shell that holds the bottom bracket. It is measured from left to right (or right to left). There are 2 standard accepted measurements, 68mm and 73mm. You shouldn't have anything other than that, although there are bigger sizes available for mountain bikes, recumbents tandems etc. So you should ave some measurements like 68/113, indicating a 113mm axle length and 68mm shell. A 73/127 is a 73 mm shell and 127mm axle and so on.

Easiest thing to do is to whip yours out, measure it and then you can get the exact same replacement in shimano cartridge variety. If you can get an exact measurement it will avoid the need to get new cranks( assuming they are both square taper variety).

Handy hint....... smother the entire bottom bracket in grease, yes it is sealed so makes no difference to performance, but helps waterproof it. In a frame all the water that gets in through seatposts, water bottle bolts etc, runs down inside the frame and collects in the bottom bracket area. Also copper grease on the threads when fitting make removal easier when the time comes.

All the best

Lloyd

 

[Mussels]

Easiest thing to do is to whip yours out, measure it and then you can get the exact same replacement in shimano cartridge variety. If you can get an exact measurement it will avoid the need to get new cranks( assuming they are both square taper variety).

You make it sound so easy, I'd need the correct tools to do that.
I intend to only buy the tools for the new setup which will probably involve destructive removal of the old one. I shall find a way of measuring it in situ.
Thanks for the help, at least I don't have to worry about whether the thread is Italian, French or British so that's a relief.

 

[Lloyd_50cycles]

Most 3 pc style bottom brackets use a 32mm flat on the drive side, which has a tendency to be a pig to remove without the right tool. Always remove the non drive side first, as it is easier to get out, and if the right side gives you grief, its easier to get to when you need to soak it in oil. Might be worth getting a shop to do it just for the headache it will save you. Last workshop I worked charged £15 to remove an old one and refit a new unit. Just to give you a rough idea....

The threads on bottom brackets are reversed on the drive side, worth bearing in mind when removing! Other than that it's all normal, and yes you can measure it in situ.

Have fun!

Lloyd

 

[Mussels]

Most 3 pc style bottom brackets use a 32mm flat on the drive side, which has a tendency to be a pig to remove without the right tool. Always remove the non drive side first, as it is easier to get out, and if the right side gives you grief, its easier to get to when you need to soak it in oil. Might be worth getting a shop to do it just for the headache it will save you. Last workshop I worked charged £15 to remove an old one and refit a new unit. Just to give you a rough idea....

The threads on bottom brackets are reversed on the drive side, worth bearing in mind when removing! Other than that it's all normal, and yes you can measure it in situ.

Have fun!

Lloyd

Your description sounds very different to what I have, the drive side needs a special socket and the adjuster has 32mm(guess) flats. I'm also told it's a right hand thread and I can't find any tools online that look like they will fit.
In view of the discrepencies I'll take your advice and get a shop to do it, I pass an LBS on the way home so I think I'll stop in there and get a quote. In the past I needed the centre spline hubs on my car changing and I got pig headed about doing it myself, this sounds like a similar job and I'm not going there again.