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9/2/2015 4:40 AM

Hi all

Dont know anything about BMX's so bear with!!

Just bought my 11yr old son a secondhand wethepeople justice 2010 20", with rear cassette broken (that was from the sellers description).

I havent much time so just want to make it safe for him to use initially then think about looks after.

So on inspection the pedals do not propel the bike, but after a little WD40 the pedals engaged better. However, I want to replace it so its safe.

My questions are:

Is it the rear hub or cassette that needs replacing? (I am getting the two terms mixed up and I know they mean different things)

Would it be easier/cheaper to replace the whole wheel or just the hub/cassette?

How do I find the size I need?

Sorry for waffle and thanks in advance.

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11/2/2015 1:44 PM
Edited Date/Time: 11/2/2015 1:49 PM

The hub is a cassette hub, meaning you have a driver that engages with hub. Usually the driver (the part with the rear cog on) has springs and pawls that engage on teeth inside the hub which drive it. (this is all oppose to a freewheel hub where the cog and ratchet screw directly on to a thread on the hub).

How to fix it all depends how technical you want to get. And if the hub is of good enough quality to make it worth it, instead of upgrading.

If it's loose ball bearings (sorry, I'm not aware of the model name's or what parts are on them!) then you're better off buying a new wheel as it's a bit of a ball ache to strip them.

If they're sealed bearings, it's a little more straight forward.
There'll be a lock nut, or bushing on the axle holding the driver on. Take that off.
You should be able to pull the driver out of the hub.
Check for damage to the springs, pawls, and teeth. Check the bearings inside the hub, and check the bearings inside the driver. If it's all good, give it all a wipe and reassemble.
You should be able to tap the axle from the drive side to knock the non drive side bearing out (the axle with the non drive side bearing will come out together, through the non drive side of the hub)
Springs and pawls vary, but they're bound to be compatible with others. Check ebay.
If the teeth are worn, you need a new hub.
If any of the bearings are gone you should be able to pull them out (removal tools are available, but a narrow flat head should do it). Sealed bearings are pretty easy to get hold of, and should have a code on the rubber cover. Give it a Google or look on ebay.
To get them back in, find a socket that's the same size as the outside race and gently tap it back in (same applies for hub and/or driver bearings).

There's some how too's out there that will have a clearer guide, and pics to help you out. Just Google "bmx cassette hub maintenance" or something similar.

There's a lot of good, reasonable priced hubs/wheels out there though. And if you find a group on fb local to you, you'll probably find something too

Hope that helps a little

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