Why do 6-speed manuals exist?

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Originally Posted By: y_p_w

Locomotives basically operate in a world where they don't need transmissions. Steam power doesn't need a transmission because it won't stall. Diesel-electrics are basically a diesel generator that powers both the electric traction motors and head-end power. I've heard of a few diesel locomotives that actually had a transmission, but they're not terribly reliable and are mostly used for low-speed applications.


Not to be contrarian, but there WERE steam locomotives with transmissions-notably the Shay, Climax, and Heisler designs. All of these used cylinders driving a central drive shaft. The Climax had two different available gear ratios-I'm not sure about the others. These were highly specialized locomotives, though. All were built for logging operations in the mountains with steep grades and tight curves. They didn't go very fast.

I know of some diesels that used hydraulic transmissions, but they are quite unusual. The diesel-electric design is preferred.

With that said, there are ways to change the torque characteristics of the locomotive. Among other things, the traction motors can be changed to be wired in series or parallel. There are also "slugs" which have traction motors but no engine(prime mover). Instead, they spread the engine power out over more axles. CSX has a bunch of these made from older GP-series cabs(with concrete poured in place of the prime mover), and I see them at the front in a double-head configuration all the time. Apparently the crews prefer the ride in a slug since there's not a big diesel engine directly behind their backs.
 
Originally Posted By: sciphi
3000 RPM in 6th is ~100 mph.

You're exaggerating. When I testdrove the Cruze Eco 1500rpm == 40mph and 2000rpm == 55mph (approximately). Its 6th gear was equivalent to a 5th gear in a standard car.

I'm looking forward to the Cruze Diesel. It's supposed to have the same 6-gear manual as the Eco.
 
I drove a C5 Corvette up to limiter at 162 speedo.

Tach was 5krpm @ 162, and 5th gear.

I shifted into 6th and tach was 3500rpm @162.

I would have pulled faster without limiter in 6th gear.

Low end torque allowed 5 gears to be fine, and 6th for low 1700rpm cruising to get that 27 mpg I've heard about.
 
Originally Posted By: bunnspecial
Originally Posted By: y_p_w

Locomotives basically operate in a world where they don't need transmissions. Steam power doesn't need a transmission because it won't stall. Diesel-electrics are basically a diesel generator that powers both the electric traction motors and head-end power. I've heard of a few diesel locomotives that actually had a transmission, but they're not terribly reliable and are mostly used for low-speed applications.


Not to be contrarian, but there WERE steam locomotives with transmissions-notably the Shay, Climax, and Heisler designs. All of these used cylinders driving a central drive shaft. The Climax had two different available gear ratios-I'm not sure about the others. These were highly specialized locomotives, though. All were built for logging operations in the mountains with steep grades and tight curves. They didn't go very fast.

I know of some diesels that used hydraulic transmissions, but they are quite unusual. The diesel-electric design is preferred.

I guess it depends on whether or not you consider a single-speed to be a "transmission".

A Shay uses reduction gearing, but I'm pretty sure it's single speed and completely mechanical. In bike terms I think it would be called a "fixie". I've ridden on a train pulled by a Shay, at Roaring Camp and Big Trees Railroad near Santa Cruz. They've got a narrow gauge setup and their locomotives include several that were previously used for logging railroads and a few Baldwins that were used on sugar plantations on Oahu. I'm looking at their inventory of locomotives, and they have three Shays, a Climax, and a Heisler.

I've also been on an miniature amusement railroad (Sonoma Train Town) pulled by a diesel hydraulic locomotive. They use small steam locomotives during the peak season, but we went on the off season and they used one of their diesels because it was easier to maintain. I asked what it was and the engineer said it was a diesel hydraulic.
 
Originally Posted By: veryHeavy
Originally Posted By: sciphi
3000 RPM in 6th is ~100 mph.

You're exaggerating. When I testdrove the Cruze Eco 1500rpm == 40mph and 2000rpm == 55mph (approximately). Its 6th gear was equivalent to a 5th gear in a standard car.

This is why the guys in another thread just accused you of doing nothing more than going around and randomly posting in threads; you want your voice to be heard, but are consistently going on some of the most specious info possible.

Sciphi is correct.

Axle ratio on the Eco is 3.83:1
Tire diameter (215/55/17) is 26"
6th gear ratio is 0.61

At 100MPH, that gives a calculated RPM of 3019.
 
Originally Posted By: y_p_w
Originally Posted By: bunnspecial
Originally Posted By: y_p_w

Locomotives basically operate in a world where they don't need transmissions. Steam power doesn't need a transmission because it won't stall. Diesel-electrics are basically a diesel generator that powers both the electric traction motors and head-end power. I've heard of a few diesel locomotives that actually had a transmission, but they're not terribly reliable and are mostly used for low-speed applications.


Not to be contrarian, but there WERE steam locomotives with transmissions-notably the Shay, Climax, and Heisler designs. All of these used cylinders driving a central drive shaft. The Climax had two different available gear ratios-I'm not sure about the others. These were highly specialized locomotives, though. All were built for logging operations in the mountains with steep grades and tight curves. They didn't go very fast.

I know of some diesels that used hydraulic transmissions, but they are quite unusual. The diesel-electric design is preferred.

I guess it depends on whether or not you consider a single-speed to be a "transmission".

A Shay uses reduction gearing, but I'm pretty sure it's single speed and completely mechanical. In bike terms I think it would be called a "fixie". I've ridden on a train pulled by a Shay, at Roaring Camp and Big Trees Railroad near Santa Cruz. They've got a narrow gauge setup and their locomotives include several that were previously used for logging railroads and a few Baldwins that were used on sugar plantations on Oahu. I'm looking at their inventory of locomotives, and they have three Shays, a Climax, and a Heisler.


Some Climaxes do have two-speed gear boxes. I meant to say that if I didn't get it out in my rambling
smile.gif


In any case, I think we can agree that they are quite different from a "normal" steam locomotive where the wheels/axles serve as the crankshaft(s).
 
Originally Posted By: bunnspecial
Originally Posted By: y_p_w
Originally Posted By: bunnspecial
Originally Posted By: y_p_w

Locomotives basically operate in a world where they don't need transmissions. Steam power doesn't need a transmission because it won't stall. Diesel-electrics are basically a diesel generator that powers both the electric traction motors and head-end power. I've heard of a few diesel locomotives that actually had a transmission, but they're not terribly reliable and are mostly used for low-speed applications.


Not to be contrarian, but there WERE steam locomotives with transmissions-notably the Shay, Climax, and Heisler designs. All of these used cylinders driving a central drive shaft. The Climax had two different available gear ratios-I'm not sure about the others. These were highly specialized locomotives, though. All were built for logging operations in the mountains with steep grades and tight curves. They didn't go very fast.

I know of some diesels that used hydraulic transmissions, but they are quite unusual. The diesel-electric design is preferred.

I guess it depends on whether or not you consider a single-speed to be a "transmission".

A Shay uses reduction gearing, but I'm pretty sure it's single speed and completely mechanical. In bike terms I think it would be called a "fixie". I've ridden on a train pulled by a Shay, at Roaring Camp and Big Trees Railroad near Santa Cruz. They've got a narrow gauge setup and their locomotives include several that were previously used for logging railroads and a few Baldwins that were used on sugar plantations on Oahu. I'm looking at their inventory of locomotives, and they have three Shays, a Climax, and a Heisler.


Some Climaxes do have two-speed gear boxes. I meant to say that if I didn't get it out in my rambling
smile.gif


In any case, I think we can agree that they are quite different from a "normal" steam locomotive where the wheels/axles serve as the crankshaft(s).

I really don't know much about the reduction geared locomotives other than Shay. In any case, I was thinking of the basic premise that steam power (like electric power) doesn't specifically require any kind of system to keep it from stalling. And of course a diesel-electric locomotive operates as a big diesel generator.
 
Originally Posted By: volk06
I wish my 5sp focus had a 6th gear for the interstate, cranking 3000rpm at 65mph in 5th gear.

That was about where my '95 Integra GS-R was. It had a closer ratio 5-speed with lower 3-4-5 gears than the regular version. However, the redline was 8000 RPM compared to the regular 6800.

I still got ridiculous fuel economy on long trips.
 
Yeah those literbikes always confused me.

100mph in first

Then the other five forward gears share the next 60-87mph


Sciphi, you're coming up on the big ten thousand! Have you decided what kind of cake you want with your ice cream?




40w8, how was the roadhandling at those speeds in the C5? Those cars are great. I havent ridden or drove one but I bet it is whisper quiet, but I wonder about how planted it is over bumps in turns, over hills at higher speeds, and how it handles the speed without a rear spoiler.
 
I was amazed at how well that C5 drove. I'd never driven a Vette,but I did a deal with a guy that had 3, all in Red White , and Blue.

I told him I'd do the deal if i could top out car.

It was a cloudy cool spring afternoon on a mostly straight bumpy 2 lane county road with a fairly strong 2 oclock wind.

The C5 drove right up to 162 with no yaw, noise , or anything.

When a truck would pull out a mile down the road, pulling power feels like braking down to 120.

There's more room than one thinks to hit those speeds because it does it in short area and time.

There was almost no one on road, few turnouts, and I knew the road.
 
Last edited:
Originally Posted By: 40w8
I was amazed at how well that C5 drove. I'd never driven a Vette,but I did a deal with a guy that had 3, all in Red White , and Blue.

I told him I'd do the deal if i could top out car.

It was a cloudy cool spring afternoon on a mostly straight bumpy 2 lane county road with a fairly strong 2 oclock wind.

The C5 drove right up to 162 with no yaw, noise , or anything.

When a truck would pull out a mile down the road, pulling power feels like braking down to 120.

There's more room than one thinks to hit those speeds because it does it in short area and time.

There was almost no one on road, few turnouts, and I knew the road.


I like it. I have to say the only reason I don't have a Base C5(The Z51 and Z06 are totally different animals) is it was just a very similar feel to the WS6. Build quality and engine performance are pretty close. They use some of the same parts like the radio, shifters, and attachment pieces. Where the Corvette is better is handling, braking and chassis refinement. The always dyno really close and run similar 1/4 mile times.
 
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