Small Sprockets for BMX Bikes
You ought to only have to replace the sprocket, absolutely nothing else. In the event that you put on an inferior sprocket to get greater gearing/slower pedalling you may need a smaller sprocket, perhaps not a more substantial one. You may want to remove a chain website link.
You are looking at a cog similar to this:
Which is about $7 on Amazon, so probably ten dollars or so from a cycle shop, plus labour. You could swap it yourself if you're just a little confident - just take the wheel off, make use of a screwdriver to pop the lock band, swap the cog and put the lockring right back (beware: the lockring is a spring and prone to go flying). With an o-ring plier they are effortless enough to reinstall you can also make use of a few screwdrivers to press it on. Really the only hiccup could be if you need to pull a chain backlink to get it be effective, then you need a chain device as well.
The key problem is 15-20 mins associated with the mechanics time, that may set you back. It's going to be less expensive if you pop the wheel down prior to taking it in, or at the least make sure you can do this (however if that is tricky you most likely desire the auto mechanic to do it all anyway).