Servicing a BMX, your step by step go to guide…
So your bikes rattling, and a bit stiff, suffered a bit outside and probably a little worse for wear, does it need servicing and some tlc… Have you got rusty Bolts too?
Simple to do you need a strip down and rebuild, it breath a new lease of life into your steed and give it back that sure footed feeling.
Start by giving it a good wash, it’s easier to work on a cleaner bike, even if the dirt looks thin and dry, it’ll shift quickly with a wash and look better once it’s done.
So, first things first, get busy pulling it apart…
Step-by-Step Strip Down
- Check the seatpost moves, and adjust it a bit maybe to;
- Pop it in the workstand…
- Remove the pedals
- Disconnect the brakes
- Loosen the Rear Wheel for chain slackening
- Remove the cranks and Bottom Bracket
- Remove the wheels
- Remove the Brake Cables, then pads, then remove the Brake Calipers
(take care not to separate the springs from the arms, their asymetrical mix them up and your brakes won’t work, worse still you might break your brakes…)
- Remove the Handlebar Stem, and Handlebars together, catching the forks
(watch out! strap a leg to the downtube with a zip-tie to save yourself some toes)
- Separate the parts on the bars
You should now be left with an almost bare frame… Maybe headset bearing cups and B/B cups remain, the seatpost can come out last, and go back in first, as will any cups you will need to replace.
The Tools Required
So what tools will you need to get this far? Only a few;
- 4mm, 5mm, 6mm, 8mm Allen Keys
- 15mm or 17mm / 19mm Spanners
- Large Adjustable and or Plate Spanner
- A small screwdriver / pry lever
- A Cross Head Screwdriver
Now you’ll need to clean all the grime and muck off it, you’ll be surprised where it’s got to… Good old soapy water isn’t a bad start, but there’s good alternatives and GT85 will gut through most grime and grease a lot quicker at this stage.
Inspecting the damage
Once you’ve got everything cleaned up, you’ll be wondering whats good and what’s worn out, it’s often obvious but if it’s not I’ll cover it all here.
Deep cleaning, and servicing requires some wire wool, and a wire brush for cleaning any stubborn corrosion.
This is the crown race that’s been abused, and this is the good one replacing it.
The bearing surface should be free from pitting and raised bumps, these will feel bad when your steer and may cause further issues as sudden wear can occur at this point.
Anything that can’t be removed with some wire wool will tell you how you’re doing, if the surface wear is extreme or uneven it’s time for a replacement part.
Acceptable level of wear will show now signs of pitting or degraded surfaces, they should show a polish when clean, you should notice a wear path but it should be free from damage.
If your bearings are at all discoloured, pitted, rusty etc… It’s time to change them too, the retaining cage as well if it’s not cleanable, you can remove it adding extra balls to account for the added room and further increasing the life of the cups.
Sealed headsets are a bit different, and will require new bearing sets. These are often one of a few standards so it’s always worth checking the spec properly, they’re often marked with a bearing code for ACB Bearings this is important as the wrong size will damage your frame.
Cleaning for Painting
Painting for Finish
You’ll need a clean dust free, still but ideally open warm air environment but lets be too idealistic about what we want and work with what we’ve got.
A clean & dust free space will mean your parts have a good finish, even and solid paint finish that will stand up to the fresh abuse it will likely receive.
Applying paint in thin layers working you way around in coats will mean a nice consistent glossy (or matt finish) with good coverage and no drips, focusing too much on coverage will mean overspray and drips… In worst cases it will mean nothing works!
Reassembly of Painted Parts
Starting with the Cups if they’ve ben removed, then crowns, the B/B, Headset and Forks are the first things to get installed and we’ll cover that in Part 2, that’s it for now folks…