16" TREK 4500 Aluminum 24 Speed Hardtail Mountain Bike ~5'4"-5'7"
13" TREK 4500 Hardtail 24 Speed Mountain Bike ~4'11"-5'2"
Hi! I have for a long time this early 2000's Trek Alpha 4500 and I want to do an upgrade project on this bike, what things do you recommend me to upgrade