Funny this should be mentioned! We had a a RE Montgomery bus that we had bought go up in flames after a run on New Years Day. Luckily, no one was injured and the bus was actually already back at our yard. Unluckily, it had just been parked next to another bus, and so, both went up in flames.
We never found out what the cause was. The driver didn't report anything strange, until he saw flames coming out the back. We speculated a stuck brake, but the only evidence we had to support that was that the fire appeared to originate from the wheel. The insurance company did no real investigation, but they did give us $16,000 per bus! (not bad considering we paid $3000 per).
Im not the biggest fan of these buses, but we got a lot of them real cheap.
Patina enthusiast and professional busman