Sure, I'd be happy to help!
To convert the diameter of a bike wheel from inches to millimeters, we can use the following conversion factor:
1 inch = 25.4 millimeters
So, we can convert the diameter of the bike wheel as follows:
26 inches = 26 x 25.4 millimeters = 660 millimeters
Therefore, the diameter of the bike wheel is 660 millimeters.
I hope this helps! Let me know if you have any other questions.