Travelling by train with a bicycle is becoming increasingly common, whether for business or leisure. These two modes of transport are perfectly complementary and are part of a responsible mobility approach. The railways have understood this and all offer solutions, more or less practical or restrictive, to take your bike with you.
In this article, we'll take a look at how things work with the SNCF, but you should be aware that all companies post details of how to transport bicycles on their websites.
This is what it says on the SNCF website:

The golden rule: a bicycle, dismantled and stored in a special bag measuring no more than 120x90 cm (85x85 for Eurostar), is considered hand luggage. No reservation is required, and there are no additional costs (except with Ouigo: additional baggage option).
Considered as hand luggage, the bike in the bag must be labeled and must not exceed the maximum authorized dimensions: 120 cm high by 90 cm wide.
It is therefore essential that the bike is dismantled and stored in a bag measuring no more than 120 x 90 cm, to avoid incurring any additional costs.

Based on the observation that there was no really satisfactory solution for transporting bicycles on trains, we decided to create the first complete range of bicycle covers specifically adapted to train travel.
This is the TRAINBAgrange, made up of 4 models, all compatible with road and MTB bikes, perfectly adapted to the 29" and each meeting specific needs:
TRAINBag Light
The TRAINBag Light is the ultra-light (1 kg) and compact (barely larger than a water bottle) bag ideal for bikepacking. It will easily find its place on your bike or in a backpack during your travels.
Link to the cover on our website: https: buds
TRAINBag Original
The classic model, with integrated wheel storage pockets. The TRAINBag Original is made from PE600D, a highly resistant material.
Link to the cover on our website: https: buds
TRAINBag Race
The TRAINBag Race is the most versatile wheelbag with independent wheel covers. It can be used on its own for maximum simplicity and lightness, or with its accessories for optimum protection. Its PE600D fabric features an abrasion-resistant, easy-to-wash TPE inner lining.
Link to the cover on our website: https: buds
TRAINBag Travel
The TRAINBag Travel is the padded cover of the range. Designed to withstand the toughest treatment, you can count on it to keep your bike in perfect condition all the way to the end of the world.
Link to the cover on our website: https: buds
Accessories
All covers in the TRAINBag range come with clever, universal accessories for optimum protection of your bike. These include the fork protector Fork Bike Protectfork protection Universal Support and the WHEELBag Race.

Fork Bike Protect
Universal fork protection, the essential complement to TRAINBag

Universal Support
Universal support to protect the transmission, isolating the rear derailleur from the ground and preventing the bike from resting on the large chainring.

WHEELBag Race
The perfect wheel cover for the TRAINBag Race, made of TPE-lined PE600D