Track bike sizing
Hi
please can I have some advice for sizing for a track bike. So, 70 kg 15 yr old boy 5’7/5’8 tall with a 6’ armspan. Currently rides a 55 cm Orbea road bike. Looking to build his own decent track bike. He is currently riding a standard 54 cm Dolan precursa on the track but wants to upgrade. Track is a mixture of disciplines on indoor and outdoor velodrome. Coach says he will end up a pursuit rider but we absolutely don't know yet. We have had very conflicting advice from experts in the field. Some say he should size up to get a straighter back and longer reach, others say size down to get a bigger drop. We have been advised to get anything from a 53 to a 59 cm. We are interested in the Dolan precursa but not fixed on it. Help!