Bicycles on commuter trains in Germany during the rush hour.

Trains in Germany fall into two main groups: subsidised regional trains and non subsidised long distance trains. The majority of trains are run by Deutsche Bahn (DB). The company is required to run the long distance services at a profit. The InterCityExpress long distance trains (ICE), DB's high speed flagships do not take bicycles, apart from bagged folded folders. However we often travel with our bagged Bromptons on ICEs.  Some long distance trains: InterCity (IC/EC) and overnight sleeper trains (CityNightLine - CNL) have reservable bike spaces. A bike ticket costs 9€ per journey, even if you change trains underway. We recommend you to reserve bike slots three months in advance if you are travelling on these trains with a bike, because they are very popular with cyclists.
You can neither reserve seats nor bike slots on regional trains. Sometimes you pay to put your bike on the train. Sometimes it's free to transport a bike on the regional trains. It varies from region to region and which ticket you buy. It is worthwhile trying to avoid travelling on regional (commuter trains) with an accompanied bicycle during weekday rush hours (07:30 - 09:00 and 16:30 - 18:00). There are limits to the number of bicycles allowed on a train. Once this is exceeded you can be asked to leave the train with your bicycle. If the train is very full the conductor may stop you getting on the train with your bicycle. It is no use arguing because the conductor will keep the train in the station and call on the Bundespolizei (Federal Police) to remove you. Just get off the train and wait for the next one. Otherwise the train will be delayed for anything up to an hour . The other passengers on the train will not be happy. The reputation of cyclists will get a black mark and the reputation of your native country will go down the pan as well.