8 AROUND THEIR THIS IS IN INCHES SO WHAT IS IT IN MILLIMETERS ITS FOR A MOUNTAIN BIKE
THE BOTTOM BRACKET CRANK GOR MOUNTAIN BIKE THIS IS IN INCHES THE LENGHT 4 INCHES AND 5/8 THE ROUND INCERT IS ONE INCH AND 3/8 I NEED THE SIZE IN MILLMETERS
Cycling - Mountain
Answers & Comments
4 5/8" is about 117mm, I'm assuming that spindle length from end to end with the cranks and bolts removed.
1 3/8" is about 35mm, and that's not a measurement used in selecting bottom brackets.
Typically, Bottom brackets sizes are Shell Size 68/73mm x Spindle length, in your case 117m, or anything close to it like 118m. I upgraded a BB on Vintage bike, the spindle length was 125.4mm, I used a 126mm BB replacement. Like 122.5mm are sold as 123mm.
Multiply the size in inches by 25.4 converts it to metric.