I have some familiarity with public transit.
The late model Novabus and New Flyers are a lot more comfortable to ride in. They had to be specific to transit buses and they could only be used in transit buses with that drivetrain layout. But it seriously limited the transmissions and axles that could be used. This allowed a shorter rear overhang and also the entire powertrain could be replaced pretty easily, and it didn't need a whole lot of space behind the rearmost seats. They have an interesting drivetrain layout, transverse engine to an "angle drive" transmission. Shouldn't be a problem for the trailers, but in the main part of the bus? How's maintenance access to the engine when it's under the floor like that? The rear axle must be very odd.
I'm not sure how the underfloor engine works with the push to have "low floor" wheelchair-accessible buses. The regular Van Hool buses used by YRT have the engine at the back as usual. I think the engine is sitting under the floor between the axles on the articulated models. York Region Transit uses Van Hool buses they're not unheard of here. I really hated these buses when they were still under revenue service because they were extremely underpowered, which were compounded by the slipping torque converter.Įven the Novabus artics are slightly faster than these things!ĭouble trailer! I wouldn't want to back up with that one! This especially goes to the heavier Flyer D901s, which takes at least 11 seconds to accelerate from 0-32 km/h or 0-20 mph on the flat! When climbing uphills when packed, they are very, very slow - they can't even manage 30 km/h on a moderately steep uphill! These buses had extremely terrible acceleration, particularly when loaded. As they are heavier than the fishbowls, they had even worse acceleration. TTC also had plenty of Flyer D901's (now retired too), which used the exact same 6v71N and had a very similiar transmission as the fishbowls. TTC used to have a lot of them in service, and remained in service until 2011. The ones on TTC's fleet were rated at 181 hp. GM New Look (fishbowl) buses have 6v71 N, which are naturally aspirated (no turbo).
just the torque converter and forward/neutral/reverse. The "old look" GM buses and the earliest "new looks" didn't even have a multi-speed transmission. I can't imagine how bad the fuel consumption was on those. The accelerator - if you could call it that - only knew two positions: off, and floored. I guarantee that in that video, the driver's foot was to the floor. Most of the time in city traffic, the bus never gets going fast enough to get out of second gear. I think the transmission only shifts based on road speed, not engine load, because the downshift to second (with the torque converter locked) happens at pretty high revs. In this video you can hear the barely perceptible shift to 2nd gear cushioned by the massive torque comverter slippage, then a while later the torque converter locks up accompanied by a big jolt, and a looong time later, it shifts to 3rd with the converter still locked with a massive jolt that you can see on the video. Here's what the buses sounded like back when I actually used public transit!ĭetroit Diesel 6V92, 3 speed automatic.
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