Class 98.7 (Bavarian BB II)

Updated: August 2026 – Two cylinder groups, one boiler, no separate tender: the Class 98.7 from the Bavarian class BB II is one of those vehicles where the designation alone reveals half the engineering. This page shows you how to read the class abbreviation and the class number, how to identify the type in a museum, and how to realistically plan sightings of vehicles like this.

What is the Class 98.7 (Bavarian BB II)?

The Class 98.7 is a branch-line tank locomotive of Bavarian origin with a divided running gear of the Mallet type. Its original Bavarian class designation is BB II; the Deutsche Reichsbahn-Gesellschaft slotted these engines into its unified numbering scheme from 1925 onward and gave them the place 98.7 there.

Both designations describe the same vehicle from two perspectives. The Bavarian class tells you how the locomotive is built, the Reichsbahn number tells you what it was used for. Together they give a very clear picture: a small, nimble machine for secondary lines, not for the main line.

Reading the designation: BB II and 98.7

Once you understand these two systems, you can infer the design of almost any German steam locomotive from its designation alone.

The Bavarian class designation consists of letters for the axle groups and a Roman numeral for the design variant. BB means: two groups of two coupled axles each – so not one continuous running gear with four coupled axles, but two independently working groups. That’s exactly the principle of the Mallet type. The II marks the second version of this class.

The Reichsbahn scheme of 1925 works differently: it sorts by purpose and type into fixed number blocks.

Number block	Meaning	Examples in the database
01–19	Express locomotives with a tender	Class 01
20–39	Passenger locomotives with a tender	Class 23, Class 38
40–59	Freight locomotives with a tender	Class 44, Class 50
60–79	Tank locomotives for passenger trains	Class 70
80–96	Tank locomotives for freight and shunting service	Class 89
97	Rack locomotives	Class 97
98	Standard-gauge branch-line locomotives	Class 98.7
99	Narrow-gauge locomotives	Class 99

Two things follow from this table: the 98.7 is a standard-gauge machine – otherwise it would sit in the 99 – and it was intended for branch-line service. The decimal .7 separates the individual classes of origin within the large 98 group from one another. How to work through such systematics in general is shown by the guide to identifying locomotive classes.

How to identify the type in the field

Why this type existed at all

Branch lines were their own chapter in the Kingdom of Bavaria: built as cheaply as possible, often with tight curves, light track and low permitted axle loads. A large main-line locomotive simply wouldn’t have got through there.

The Mallet type solves this problem elegantly. Instead of one long, rigid running gear, the locomotive gets two shorter units; the front one can swing sideways. That spreads the weight across more axles without increasing the rigid wheelbase. For branch lines that was exactly the right answer – demanding in maintenance and upkeep, but operationally fitting.

You think along similar lines with other branch-line and shunting engines: the Class 98 collects the whole branch-line family, while vehicles like the Class 89 were designed for shunting duty at stations. The distinction between main-line service and shunting duty is almost always the key to correctly placing a tank locomotive.

Where to look for vehicles like this today

You won’t find this generation in a state railway’s scheduled service any more. Anyone wanting to see one inevitably ends up at museums, societies and special events. In Bavaria, Lokwelt Freilassing is one such address: it shows its vehicles in the historic roundhouse of a former motive power depot, exactly where they were once serviced. The research therefore follows a different pattern than for scheduled operation: you’re not looking for diagrams, but for dates.

This order has proven effective:

• Check heritage railways and railway museums to see which historic vehicles they actually house – the fleet is usually listed on the society’s pages.
• Collect event dates: museum festivals, season openings and anniversaries are the days when vehicles come out of the shed.
• Follow forums and community reports, because short-notice changes appear there first. The guide to heritage railways and special working dates shows how to work through these sources systematically.
• Question operational status: a vehicle can be on display, dismantled, or under restoration. That changes over the years and is rarely up to date online.

For photo technique, steam has its own set of rules anyway: steam and smoke change the exposure, and backlight can either emphasise the plume or swallow it. The guide Photographing steam trains goes into light, location and shutter speeds in detail.

Common mix-ups

Verdict

The Class 98.7 is a textbook example of how much a designation can tell you: BB II describes the divided Mallet running gear, and the 98 places the vehicle among the standard-gauge branch-line locomotives. Anyone who can read both systems needs no spec sheet to roughly place the locomotive. Today it’s seen only in a museum setting – and there, careful documentation of date, location and condition counts for more than the sighting alone.