CRJ100 --> 200 change-over?
 

Does anyone know when, during production, the CRJ100 changed to the CRJ200? What serial number does the transition take place around? It would be somewhere in the upper 7400s I believe

I thought it was when they starting putting the 3B1 engines on as standard, looking at airfleets.net there doesn't seem to be definitive line, but it does seem to be around the mid 7000s. As in 7500 give or take a few hundred.

My understanding from something I read a while back on Bombardier's website, the CRJ 100 originally had the "A" engines, the 200 came with the "B" engines, and the "ER" model is a 51,000 gross model and an "LR" is a 53,000 gross model. There are other differences but that's one way to tell them apart.

I was told the difference between the 51k and 53k was a pricey STC that upped the MLG tire pressure up 12 or so psi.