UK

There are some local services that carry bikes - but in the case local to me the utility of the implementation is questionable for regular use.

Some UK trains are bike-friendly, e.g. East Coast trains let you take a bike for free with any standard ticket. But its vital to check beforehand. Some (eg virgin trains) require you to book a place a day before (and there are only 4 places per train), others (eg Stansted Express, or Cross Country trains) won't take bikes at all, unless its a folder. Others, will allow bikes on for free without booking, so long as its not at peak times

North East England

Go North East (part of the Go Ahead Group) has a service that will carry one bicycle inside the bus - this is the service between Consett and Sunderland details here

In terms of "how common" - in theory all the buses on that service should be able to carry a bike however only the buses dedicated to that route have the bike specific kit.

Scotland

No bikes allowed on the stage coach buses. At times when I've had to transfer my bike for repair, I've taken off the wheels. In my experience most bus drivers will let you take the frame, albeit grumpily.

Wales

There is a "Brecon Bus" service that runs from Cardiff <> Brecon every Sunday & Bank Holiday Monday. Details can be found here

In general though, for local services, wouldn't it be more efficient to, erm, cycle yourself?

London, UK

That said most buses in London have space to carry prams, wheelchairs and so on. In theory they can carry bikes too, although it's rarely seen.

Quite often this carry space is at the discretion of the driver - many times the mother of the second or third pushchair to arrive is refused entry because they've already got the limit. Some drivers are more flexible than others.

I did once see it though, it was a rainy day and someone had punctured and the driver took pity on him. I presume that if a wheelchair wanted to then get on, though, that the cyclist might have been unlucky ...

Australia

Brisbane used to allow bikes to be carried on special racks at the back, though I believe that this is no longer available.

Canberra Similarly there are some routes that let you put a bike on a special rack on the rear of the bus.

I also found a link to an interesting site that covers some other cities in the world, as well as this one that covers bikes and public transport interactions.

Chicago

CTA:

The CTA allows bikes on a rack at the front of its buses.

Bicycles are permitted on the 'L' (CTA trains) every weekday except from 7 am to 9 am and 4 pm to 6 pm (with certain exceptions where crowding is anticipated). On Saturdays, Sundays and holidays (except when prohibited), bicycles are allowed on trains all day.

Metra:

Bikes are permitted on weekday trains arriving in Chicago before 6:31 a.m. and after 9:30 a.m., departing Chicago before 3 p.m. and after 7 p.m., and on all weekend trains.

Bikes are accommodated on a first-come, first-served basis, and those with mobility devices always receive priority. There is no guarantee that bikes can be accommodated on an initial or return trip (including late night trains), and crews have the right to refuse bikes in the event of overcrowding or depending on the needs of customers with disabilities.

During special events, there is an increased likelihood that bikes cannot be accommodated. Bike warnings are in place for these annual events:

• St. Patrick's Day Parade
• Blues Festival
• Taste of Chicago
• Lollapalooza
• Air and Water Show

Stockholm, Sweden

Bicycles are allowed in commuter trains except during peak hours (6-9 and 15-18). Getting in and out trains with a bike is not allowed at Stockholm C and Arlanda C.

Bicycles are not allowed in busses and in the underground network.

Columbus, OH

bike mounts on the front of the bus and runs specials like 'Bring a Bike ride for Free' and the buses do an almost protective job with the bikers.

New England

Massachusetts

The MBTA in the Boston area has bike racks on a fairly substantial number of the busses (70%, according to the web page). The Red, Blue, and Orange line subways, and Commuter Rail allow bikes outside of peak hours.

The Pioneer Valley Transit Authority in Western Massachusetts (Amherst/Northampton area, with several colleges) has bike racks on their busses.

New Hampshire

Manchester Transit has bike racks on most busses. Some busses have bike racks which accommodate three bikes.

Concord Area Transit has bike racks on most busses.

Nashua Transit has bike racks on all busses.

Advance Transit in the Upper Valley region of Vermont and New Hampshire (Hanover, NH, White River Junction, VT, the Dartmouth College area) has bike racks on many of their busses.

Vermont

CCTA (Burlington area) has bike racks on all busses, as well as bike lockers.

GMTA (serves rural Vermont, and recently merged with CCTA) also has bike racks on all buses.

The Amtrak Vermonter rail line (connecting St. Albans, Essex Jct. (Burlington), Springfield Mass., New York City, and Washington DC) now offers carry-on bike service as of May 2016. (There is a limit of 3 bicycles per train, a $10-$30 fee depending on destination, and bicyclists are asked to arrive early at the station)

Maine

METRO Bus (Portland) has bike racks on all busses.

---

Even busses with bike racks can only carry two bikes at once, which means that if many people use them, you may need to wait a while before finding a bus with space, and some of them have restrictions (such as not on express busses, or not when the busses are replacing a train). In general, I find it's best not to rely on being able to take bikes on public transit, but use it as a backup option for when the weather turns bad, you have an injury, or something of the sort, and you still want to take your bike home.

Toledo, OH, USA TARTA has bike mounts on the front of their buses.

TriMet (Portland metro area, Oregon)

• Busses have bike racks mounted on the front of the bus. A rider just needs to let the bus driver know at the stop that they wish to load/unload the bike. All busses have racks. Bikes do not go inside the bus. The racks hold 2 bikes. No bikes are allowed inside the bus.

  

• The light rail cars have a section with hooks to hang bikes + an open area that allows for a few bikes. On type 2 and newer trains, 4 bikes can be hung in each car, and there are typically 2 cars per trainset. It is sometimes possible to fit more bikes in the that area – some people will create a second hanger using a U-lock between the bike wheel and the railing, but this is discouraged by TriMet.

  On older type 1 (high floor) cars, one bike can be leaned against the operator cabin on each end of the car (if the cabin is unoccupied), and there are 4 additional spots where a bike can be leaned against the wall, for a total of 5-6 bikes per car. There is a restriction on all trains that bikes are only allowed if room is available.

  

  
  _{(source: trimet.org)}

• Streetcars also have a designated bike area limited by room available.

http://trimet.org/howtoride/bikes/index.htm

^{All images from TriMet's website}

Delaware -- DART claims that all its buses have bike racks (they confirmed this when I called them). I recently rode one of their buses with a bike, and this particular bus didn't have a rack. I had to put my bike in the luggage compartment under the bus; this is apparently standard procedure. The bike rattles around in there as the bus moves, and there's other luggage loose in the same compartment.

San Francisco Bay Area

Anything in the 9 counties, including the cities of San Francisco, Alameda, Oakland, Berkeley, and Richmond. Making this community wiki, so please add the ones you know. For those of you outside the bay area, it's 9 counties and about 40 different public transit agencies and there's all kinds of interlinks/transfer opportunities between them, so I think one big answer for all of the SF bay area might be the best way to present the information:

• BART (Bay Area Rapid Transit; light rail / subway connecting most, but not all of the bay area counties) — bikes are allowed on all trains, (during commute hours, not allowed in first 3 cars, or if the train is full). Folding cycles are always allowed. http://www.bart.gov/guide/bikes/bikeRules.aspx
• SF Muni (light rail, buses, cable cars, etc within the city of San Francisco) — Racks on the front of most buses, but not any of the other vehicle types. Folding bicycles are allowed inside all Muni vehicles (with the exception of cable cars) http://www.sfmta.com/cms/bcomm/BikesonMuni.htm
• Golden Gate Transit (GGT, crosses the Golden Gate bridge to connect San Francisco to the two counties north and also ferry service between Larkspur and SF) — racks on the front of some buses and racks underneath on others. Ferries allow a limited number of bikes. http://goldengatetransit.org/services/bikes.php
• AC Transit (Alameda country, with transbay buses to SF) — All busses have bike racks that hold two (or three on newer buses!) bikes on the front. Some also have storage space below that can hold (officially) 2 more bikes. Folded or collapsed bicycles may be carried on board anytime as long as they do not block seats or aisles. http://www.actransit.org/rider-info/rider-guides/bikes-on-buses/
• Caltrain (rail between SF and Santa Clara) — special cars for the bikes. Folding cycles allowed. http://www.caltrain.com/riderinfo/Bicycles/Bicycle_General_Info.html
• Samtrans (SF connection down peninsula to Palo Alto) — Buses are equipped with bike racks which hold two bikes. Two additional bikes are allowed inside the bus depending on passenger loads. http://www.samtrans.org/bikes.html
• Sonoma County Transit (primarily connects cities within Sonoma County and also provides local transit for some cities in the county) — racks on the front of every bus. Most racks accomodate 3 bikes, some only 2. If the rack is full and there's room on board, a couple bikes can go on board.
• Santa Rosa CityBus — Bike racks with 2 spots on the front. Can put bike in the wheelchair area if rack is full but bus isn't full.
• VTA Bus (Santa Clara Valley Transportation Authority Busses; Covers the South Bay Area) — racks on the front of every bus. Racks accomodates 2 bikes. If the rack is full 2 bikes are allowed inside, at the driver's discretion. http://www.vta.org/bike_information/bikes_on_transit.html

Vancouver (BC) Translink has roughly the following rules for bikes on transit:

• All buses have a bike rack on the front for 2 bikes.
• Bikes are allowed on the Canada Line skytrain at any time. (There is a bike specific area in each car
• The seabus allows bikes at any time.
• Expo and Millenium line skytrains allow one bike per car during 'off' hours. In other words, you are allowed a bike heading downtown at any time other than 7-9AM weekdays. You are allowed to take a bike heading away from downtown at any time other than 4-6PM weekdays

Dallas Area

Most of the Buses in the Rapid Transit system have bike racks on the buses and you can take your bicycle into the cars on the Light Rail System.

Information is Here at the Dart Website

New Zealand

Intercity took our bikes as long as there was some space in the cargo hold. The rule there is that the driver gets to decide whether your bike goes on (depending on available space), so it helps to remove the pedals and turn your handlebars and cover the oily bits, but this is not always necessary. Most drivers were very friendly and will make sure your bike is properly placed to avoid damage to it.

One time they even went so far as to exchange a small passenger van for a full-size bus for 10 people just so our bikes could get on.

Note that these are not local busses.

Christchurch http://www.metroinfo.co.nz/info/Pages/bikeracks.aspx

Almost all (27) bus routes have a 2 place rack out the front. No bikes inside the bus, but you might get away with a folded one. Central Bus Exchange has special loading doors for bikes. No cost for taking a bike. Minimum wheel size is 16"

There are no passenger trains

Ferry - the Diamond Harbour ferry will take bikes as deck cargo, at discretion of staff. Bikes not to go inside.

Auckland https://at.govt.nz/bus-train-ferry/luggage-bikes-animals/bikes-public-transport/

Bus - No bikes on any bus unless its a folder. There are bike racks on busses on Waiheke Island, but that's all.

Ferry - free at any time. Different vessels vary, just ask.

Trains will take bikes for free if there's room and at discretion of staff. Don't take a full sized bike at peak time. Folders can go at any time and stored under a seat. Use the middle car of every three, (second and fifth car of a six-carriage train)

Dunedin http://www.orc.govt.nz/Documents/Content/Information%20Services/buses/2015/Carry_on%20Guidelines_dbl%20sided%20flyer.pdf

Busses for 10 of 29 routes are required to be fitted with bike racks. The others probably have bike racks, but its not contractually required. Aim is for all busses to be bike-racked by July 2016. Minimum wheel size is 20"

No trains or ferries in Dunedin.

Wellington https://www.metlink.org.nz/assets/Publication-PDFs/Travelling-by-bicycle-booklet-december-2015-WEB.pdf

Busses - folded bikes only, carried by the passenger, at no additional charge. No bike racks available.

Trains - Bikes travel free, but only folders are allowed at peak time. Stations have bike parking.

Ferry - yes, 6-8 bikes permitted for free per crossing, on a first come first served basis

The Netherlands

Bikes are allowed on all trains, except during rush hour (7-9 in the morning, 16-18 in the afternoon). But usually you can get away with it during those times anyway. You do need to buy a separate ticket for your bicycle, which costs €6 (August 2014, see this national railways page) and is valid for one day, irrespective of distance.

High speed trains (ICE, Thalys) usually do not transport bikes (with few exceptions). Thalys will transport a bike if it is packed in a bag measuring 120 x 90 cm, or a folding bike. Source: Thalys - Luggage on board

There are no local busses that allow or even have space for bikes, but most local distances are better done by bike anyway.

Folding bikes are considered luggage and allowed on all public transport.

Bikes are difficult to get onto what subway systems we have, but I think no-one will stop you if you try.

Milwaukee, Wisconsin, USA

From the Milwaukee Country Transit System website:

All Milwaukee County Transit System buses are now equipped with bike racks which are simple to use. This will make it even easier to leave your car at home for your commute, head out to explore Milwaukee County Parks and bike trails, or enjoy a bike ride on your lunch break. Each rack holds two bikes and use is free with your bus fare.

Seattle, Washington and environs

• Nearly all King County Metro and Metro-operated Sound Transit buses are equipped with three-bike racks. Folding bikes are allowed on the bus. Non-conventional (trike/recumbent) bikes are not supported, and neither are bicycles with front racks that do not allow the rack's hook to sit atop the front wheel.
• One exception to the above is empty, dead-heading buses across the 520 Evergreen Point Floating Bridge between Seattle and Redmond (aka Microsoft) - the bridge has no bicycle facilities and a large number of commuters; drivers have been known to let passengers bring their bikes aboard. The Microsoft dedicated shuttle may have reduced this behavior, however.
• The Sound Transit Express buses are equipped with two-bike racks.
• The Link light rail trains have two bicycle hooks per train, plus room for standing bicycles. There have been some complaints about the stated limit of four bicycles per car and the categorization of the bike hook area as 'first-come, first-served luggage storage'.

One of the main reasons for the King County Metro bus-bike system was the 1991 passage of the ISTEA, which allowed the county to receive a nearly $1 million grant to add bicycle racks to every bus. This and later sources of federal funding have also been used to update other systems in the US.

Madison, Wisconsin

All Madison Metro buses have bike racks that hold two bikes. Tell the driver as you leave the bus that you'll be taking your bike off.

Bikes are not allowed inside the bus.

More info: http://www.cityofmadison.com/Metro/planyourtrip/bikeRacks.cfm

In Hebden Bridge, UK (and the surrounding area) the 'Hebden Bridger' buses have a bike rack on the back of them.

Twin Cities (Minneapolis-St.Paul, Minnesota, USA) has a bike rack for two bikes on all buses. If the rack is full, the driver may give permission to bring your bike inside the bus. The bike racks are used pretty frequently: it's not unusual at all to see a bus with a bike or two on the front.

http://www.metrotransit.org/bicycle.aspx

To quote from above (as of August 2014 -- note that the trains are included):

All Metro Transit buses and trains have bike racks so you can pedal for part of your trip and ride for the rest. Every bus has a bike rack on the front bumper that accommodates two bikes. There are four bike racks inside each light-rail car and spaces for two bikes on every Northstar train car. In addition, there are bike racks and lockers at most stations.

Waterloo, Ontario, Canada

All the main routes have front mounted bike racks. The secondary routes have them on most (but not all) buses.

Toronto

In Toronto, buses have a fold-down rack on the front (outside) which will fit two bikes.

The racks are usually empty.

I've used them occasionally (e.g. for a flat tire).

You can takes bikes into the subway ("Underground") system too, but not during weekday rush-hours (06:30-09:30 and 15:30-18:30).

Washington DC

WMATA buses have a bike rack on the front.

Ottawa, Ontario, Canada

Ottawa has what they refer to as their rack and roll programme. Most major cross-city routes have racks. They also let you take your bike on the O-Train. In my experience it's often common to see buses without racks when they should have them, although I haven't consistently used them for a few years so things may have gotten better. It is common for the bike racks to be full during rush hour if you get on too far into the route.

In Norway

The Oslo Area

#Ruter allows you to bring a bike on the bus as long as it isn't troubling other passengers. Most busses have room for strollers, wheelchairs and bikes.You have to pay a child ticket for the bike.

I believe most public transport companies in Norway follow the same practice. I even brought a moped on the bus a couple of times.

Bergen

You can take a bike on buses in area around Bergen, for half the price of an adult ticket.

Pittsburgh, Pennsylvania

Port Authority of Allegheny County which serves Pittsburgh, PA and surrounding areas has bike racks on all busses and allows bikes on light rail cars and incline rail (funicular).

Cleveland, Ohio

All buses have racks for 2-3 bikes. The RTA (trains) permit bikes, based on operator discretion.

http://www.riderta.com/racknroll

Spain

Bikes can go on all trains except the high-speed trains (though I've heard of exceptions to the latter).

Update: since 2015, bikes are officially allowed on the Renfe highspeed trains for free if they're packed up in a bag and no more than 120cm x 90cm x 40cm. Some trains may have a luggage van and then they'll want you to put it in the luggage van, but if theres no luggage van you'll just have to squeeze it into the corridor or something, unless you've got it small enough to fit on the luggage racks (and they're not full of luggage already)

We were once told our bikes couldn't be carried on a very small local train, but our Spanish wasn't good enough to understand why! (so we went by bus instead)

Bus travel is very popular in Spain, because its cheap and they go everywhere. Intercity busses are coaches, with loads of space in the hold underneath. We had no problem taking our mountainbikes on ALSA buses in Andalucia, but you MUST have them in a bag, with the front wheel removed to make them more compact and to protect other people's luggage from oil etc. Bikes are classified as outsize luggage, so you have to buy a ticket but this was typically about 5euros for each bike on a journey of several hours. Our "bag" was bought locally for a few euros and consisted of a thin cover designed for covering motorbikes strapped up with a roll of parcel tape!

Toulouse, France

Bikes are allowed in the tram, except during rush hours.

Bikes are also allowed in the suburban train, including during rush hours.

Halifax, Nova Scotia, Canada

A number of Metro Transit buses have a fold-down rack on the front that will hold up to 2 bikes, and most of the time they seem to be empty.

There is a guide to using the racks, and the routes with bike racks can be identified on the transit schedules page.

You can also take your bike on either of the Dartmouth-Halifax harbour ferries.

Dayton, Ohio

RTA in Dayton and surrounding communities have bike racks on the front of the busses. However, they only hold 2 bikes and require the rider to fold and unfold the rack as needed.

However, with the Miami Valley Bike Trails and the spirit of the Wright Brothers, you don't really need RTA to get to most places.

Germany

Local trains

On Deutsche Bahn, local trains ("Nahverkehrszüge") usually carry bikes. Many trains have special open areas for big objects like prams, bicycles and wheelchairs ("Mehrzweckabteil"); in others bicycles may be put into the corridors. Sometimes bikes are not allowed during peak times, like weekday morning and afternoon; this depends on operator and type of train. You may be denied boarding if there is not enough space for the bike(s); this is not unlikely to happen for larger groups, during peak times and on trains with little space.

Long-distance trains

On long-distance trains, bicycles are only allowed with a reservation, and only on trains which have bicycle compartments (which most do not have).

Buses, trams and subways

Again this depends on the region and operator. Usually bikes are only allowed outside peak times, and only one or two bikes per bus/carriage, because of space restrictions.

Dresden, Germany

Public transport is great for bikes here. You can take your bike on any bus, train, or tram. However, you do have to purchase a concession ticket for the bike.

Baltimore, Maryland

Bicycles are permitted on the light rail and the metro, except if it's very crowded - which generally corresponds with when there is an Orioles or Ravens game happening. Almost every light rail, metro, and MARC stop has bike racks at the stop.

MTA buses have racks that can fit 2 bikes. A bicycle is not allowed on board.

MARC trains permit only folding bicycles.

More info: http://mta.maryland.gov/sites/default/files/MTA-Bicycles-Brochure-2011.pdf

Urbana/Champaign/(Parts of) Savoy, Illinois, USA

The Champaign-Urbana Mass Transit District has almost all buses which can take 2 bikes in the front. The rules are here.

New York City

You may bring your bike on the subway at all times (though it's quite rude to do it at rush hour).

You may bring your train on the commuter railroads during off-peak times. However, Metro-North and the Long Island Railroad (LIRR) each require a bicycle permit which costs $5 and has lifetime validity (for the life of the paper it's printed on, seemingly).

There are no bike racks on any buses.

See http://web.mta.info/bike/

RTP area of North Carolina, USA

Most of the buses that I've seen in RTP area of North Carolina seem to have them. I've carried my bike on the Raleigh Durham Express bus several times.

New Jersey Transit (New Jersey/New York)

Paraphrased/quoted from here.

Trains:

Folding bikes are usually allowed.

Standard-frame bicycles are permitted on many NJ TRANSIT trains as described below: On weekdays - Bicycles are permitted on all weekday trains on all lines except inbound trains that end in Hoboken, Newark or New York between 6 a.m. and 10 a.m. and outbound trains that originate in Hoboken, Newark or New York between 4 p.m. and 7 p.m. These trains will be designated by a bicycle symbol in public timetables.

On weekends - Bicycles are permitted on all weekend Raritan Valley, Gladstone, Montclair-Boonton, Main, Bergen County, Pascack Valley, Port Jervis, and Atlantic City Line trains. These trains will be designated bike trains and will accommodate up to 12 bicycles per train. Larger groups may be accommodated with advance reservations by calling our Group Sales Department at 973-491-7220. Bicycles are also permitted on all Northeast Corridor, North Jersey Coast Line and Morristown Line trains with the exception of trains ending in New York between 9 a.m. and 12 p.m. and trains originating in New York between 5 p.m. and 8 p.m. Trains on which bicycles are permitted may accommodate up to 2 bicycles on each single-level rail car and up to 8 bicycles on each multilevel rail car subject to crowding or the accessibility needs of other customers.

On holidays and business days before holidays - Bicycles are not permitted on trains (for most holidays you may care about).

If the trains are down (and they're running busses instead), you can't bring your bike.

Buses:

Bicycles are permitted at all times on buses with bike racks on the front or with underfloor luggage compartments on a first-come, first-served basis. Currently half of the NJ TRANSIT bus fleet is "bike friendly". Bicycles can be accommodated on all buses in the NJ TRANSIT Southern Division (generally the area from Princeton/Trenton to Atlantic City and south).

No tandems, no child seats.

Light Rail:

Bicycles and Segways can be carried aboard River LINE at all times. Bicycles and Segways are carried on-board Newark Light Rail and Hudson-Bergen Light Rail during weekday off-peak hours only (9:30 a.m. to 4:00 p.m. and 7:00 p.m. to 6:00 a.m.), and all day on Saturday, Sunday, and state holidays.

Don't leave your bike unattended and don't block the aisles.

Japan

JR East trains

No JR East trains allow unpacked bikes, but folded or packed bicycles (in bags) are usually fine, no additional fee required. Trains tend to be packed, so placing a bicycle in the very end of a frontmost or rearmost car is least troublesome. From the observation, JR Takasaki line is the least strict and an unpacked bicycle can be taken onto it without any trouble. The latter is rather a result of loose control and not JR East rule. Narita Express trains belong to JR East but train configuration does not allow to put a bicycle with only one wheel detached inside. It is possible to place the bicycle into the aisle, but way for the drink selling cart may be obstructed. It is possible to place smaller bicycles into the baggage area.

JR Shikoku trains

JR Shikoku train lines do not charge an additional fee for a bike, but they are especially picky on what type of a bike bag you have. Make sure there are no uncovered bike parts sticking out of the bag - saddle included. Cover them with a plastic bag if no other options are available.

JR Hokkaido

Hokkaido line allows bicycles to be taken as is, with additional charge, but there's somewhat loose control and it is not known how strict are bicycle bag regulations. No data for other JR Hokkaido lines.

Shinkansen (bullet trains)

As long as it is in a some sort of bicycle bag it is fine and no extra charge is taken. Put the bicycle bag behind the rear seat of a car. People carrying bicycles are common on bullet trains, so there's a possiblity you may need to check out several cars before finding a free place. The frontmost and rearmost cars are usually free. It is usually safe to leave the bicycle unattended. If you don't have a seat in the same car, it is okay to keep the bicycle near the door, as long as it is not blocking the passage between the cars. It is recommended to secure the bicycle/bag somehow, because Shinkansen tend to be surprisingly bumpy at times.

Ferries

This depends on a particular ferry line, but most of the time it is possible to bring a bike with some additional fee. Ferries between Honshu and Shikoku island in Shimanami Kaido biking area take a bicycle for a basic fee. Most ferries in other areas allow you to secure your bike in the car area of the ferry. Bikes packed in bags can be taken for free.

Buses

City buses usually do not allow bikes onboard and in fact there's very little room to place them inside. Japanese buses do not have front-side bike carriers (as seen in the USA)

Private lines

Tokyu lines, Keio lines, Odakyu lines (Tokyo area)

Same rules as JR East: no naked (uncovered) bikes, packed bikes are OK, no additional fee, any size.

Odakyu romance car

Packed bikes are fine with no additional fee. There's no space to place a bicycle but aisles are wide and putting them in the aisle is normally accepted by the staff.

Rural lines

Many rural private train lines allow taking bicycles onto the train with or without additional fee (depends on a particular line). Some lines limit the bicycle-free area for the suburbs only. Some lines have time limits (no rush-hour, for example), but on time-limited lines on the weekends and holidays bicycles can be taken on the trains with no limits. For the detailed information refer to the : Cycling Lines Wikipedia article (Japanese only).

Cycling events

In case of a large cycling event some lines allow taking uncovered bicycles onto a train for a limited period of time. Needs to be clarified right before the event.

Bangalore, India
Regular buses do not allow cycles, especially since the door is too small to take it through.
Ac-buses are supposed to allow you to take your cycle. You will be charged an extra 'luggage' fee which keeps changing so I shan't bother mentioning it. However, during peak times conductors will often disallow you due to lack of space. If you want to travel by bus, try doing so in the early morning or early afternoon.
Metros do allow cycles

Switzerland

Generally: if there is space you are mostly/often allowed to bring your bike on the bus/train/tram. You are however expected to pay for it (generally a half-fare, the same kids pay).

"Long distance" ;) trains ("Intercity")
You're allowed to bring bikes, but only in designated wagons which have a special bike compartment. Most of the inter-city train lines have at least one wagon with such a compartment. There are official bike-tickets you can buy, even ones covering an entire year (e.g. for bike-train-bike commutes). Offical info from SBB about bikes on trains

Regional trains ("Interregio")
Mostly the same applies as for the trains above. Not all regional trains have bike compartments, but if you load your bike diligently without causing a hassle for everyone this mostly isn't a problem. (Official sources might contradict this though. ;))

Regional busses ("Postauto") You're generally allowed to bring your bike. Limitations might apply excluding certain lines and/or time-ranges.

Urban railway ("S-Bahn")
You're generally allowed to bring bikes (many people do this) and many wagons have special compartments with space for many bikes. On some routes there are some limitations though (e.g. you might be forbidden to transport bikes in the middle of rush-hour).

Urban busses/tramways ("Bus/Tram")
This depends on the specific city. In some (e.g. Bern) transporting your bike is no problem whatsoever, you are expected to buy a ticket for it though (50% of adult full fare). People tend not to do this very often though (unless the bike is broken or similar) as the distances covered by this kind of public transport are very easily bikeable (and biking would generally save you a good amount of time).

Latvia

Inland intercity trains ?

Bicycles are allowed on inland intercity trains operated by Pasažieru vilciens (inland railway public transport service provider) for a fee which amounts to a baggage ticket.

• Bicycles should be placed in bicycle holders, if a railway wagon is fitted with such holders. Railway wagons with bike holders are marked with a label on the doors (white bicycle, blue background).
• In railway wagons without bicycle holders bicycles can be fitted between the seats, but not more than 5 per wagon.
• Group of cyclists (more than 15 people with according number of bicycles) should contact railway operator to arrange the possibility/time of loading a certain amount of bicycles in a timely fashion to avoid delays.

Riga

Bicycles are allowed to be carried in public transportation operated by Rīgas Satiksme (bus, trolleybus and tram operator in the city of Riga) without extra cost. There are some basic rules, though:

• Other passengers should not be troubled or injured, which rules out rush hours;
• No damage should be done to the carrying vehicle;
• Bicycle should be placed in the most spacious place of the vehicle and secured so that it doesn't fall or move incidentally.

Sources (English):

• What a public transport passenger has to know?
• Public transport (in Riga)

Liepaja

Bicycles are not allowed to be carried in public transportation operated by Liepājas sabiedriskais transports (bus and tram operator in the city of Liepaja), except kids' tricycles.

UK Trains

Virgin Trains accept bikes, however you must reserve a space first.

You can book at the station ticket office at least 15 minutes before the train arrives, or over the phone [0344 556 5659, Option 1] at least 60 mins. before (as you have to wait for the system to update and then collect your reservations from a self-service machine).

You can book your ticket separate to reserving the bike space - but make sure you are very clear with the call centre that you CAN just reserve the bike space as they often are not sure of the procedure.

NOTES:

• There are only 4 standard spaces or 4 hanging spaces on any train.
• Spaces are always in the Quiet Coach, which is the last coach on the train, usually the Northern end but always furthest from First Class.
• You MUST tell the platform guard you have a bike so he can open the door for you to get on (its sometimes requires a guards key to open, depending upon the train)
• You MUST tell the train manager on the train that you have a bike and which station you are getting off at, otherwise they won't come and open the door for you.
• The staff are usually very good and helpful.
  
  
  

London Midland accept trains for free with no booking required.

However, there is very little space for bikes and you have to use the area with fold-down seats reserved for wheelchairs, provided there are no wheelchairs on board. If that space is taken, then you have to stand with your bike in a doorway.

The wheelchair space is just too small for a roadbike, although it can fit on a diagonal, but an MTB fits nicely.

NOTE: Any LM train arriving into London Euston between 07:00 and 10:00 does NOT accept non-folding bikes, regardless as to the stations you are using. This is also true for trains starting at Euston between 16:00 and 19:00...although guards are more lenient the further out from London you are starting.

For example, if you get a train from MKC to LBZ (2 stops) at 06:45, you cannot take a bike on board because it reaching EUS at 07:45.

Austin TX USA

• Austin buses have a fold-down rack in front that can accommodate two bikes.
• MetroRail (a commuter line) can accommodate eight bikes per car.
• Some MetroRail stops also have bike lockups.

SLC to Provo Areas in Utah

The buses in this area generally have front-mounted bike racks, very similar to those pictured in other posts. They can handle 2 or 3 bikes. If the rack is full, a driver of an underloaded may allow a bike onto the bus, but this is at their discretion.

The larger trains (FrontRunner) generally have a bike-specific car. Riders are encouraged to use those. If there isn't one, a bike may usually be kept in a passenger car in the boarding area at the doors, although conductors may not allow this on crowded cars. In general, they are very accommodating. Gas-powered conversion motors are very strictly forbidden. I've seen the transit police summoned when a rider didn't want to remove his from the car. The threat was enough.

The smaller trains (Trax) allow bikes, I think, but I don't know much about how many or how they're handled.