or.h:#define ROUTER_REQUIRED_MIN_BANDWIDTH (20*1024)
But we raised the recommended minimum listed on the website to 100KB, and then again recently to 250KB.
Now, we should be aware that this #define is used for both relays and bridges. But a tiny bridge is increasingly looking like it will drag down users who use it. But we also don't want to skew the incentives so a 100KB/s bridge sets her BandwidthRate to 250KB so her bridge can start.
In any case, I think raising from 20 to 100 is an easy and wise step. We should discuss whether raising to 250 is wise too.