Precise Chain Alignment for your BMX Bike

You could spend hours trying to get your chain alignment sorted out by eye. Or you could do it the quick way. Take a few measurements, do a couple of calculations and you are done. The end result is a perfect chain alignment each and every time.
The measurements
1. Measure from the inside (bb shell side) of the chain ring to the opposite side of the BB.
This is why we need the folded piece of paper for a straight edge, it could be anything with a straight edge.
Example measurement: 74mm
2. Measure the width of the bottom bracket shell
Example measurement: 68mm
3. Measure the offset of the chain ring, the edge of the chain ring to the center of the teeth
Example measurement: 2mm
Calculations
1. Center of the bottom bracket shell
68 mm / 2 = 34mm
2. The Chain line
74 mm - 34 mm = 40mm
3. Add the offset
40mm + 2mm = 42mm
4. Rear sprocket offset
110mm / 2 = 55mm
55mm - 42mm = 13mm
A massive thanks to Paul Knox who has many years experience in the bike industry. Paul is a wealth of BMX knowledge that we will be drawing from to create more handy video to help set up your BMX bike perfectly.

[@eskimo4130]

Legend. I forgot the calculation and was looking for the easy way out. You have my upmost thanks.

[@brianleeBMXDad]

Thank you! So on 😊

[@jessarellanes6648]

I think I need to check this on my bike.
Thank you, I didn't know that.

[@nuclearguitarfare4653]

Great info

[@jacobjames1171]

I got lost after he folded up the paper.

[@bmxultradotcom]

I’ll add instructions to the description later today to make it easier to follow.

[@jacobjames1171]

Thank you. I think my cruiser alignment is off. I'd like to try this technique.

[@bmxultradotcom]

@@jacobjames1171 the measurements and calculations are in the description now. Let me know if you need anything else.