| Seks |
| What do they mean? 50% and 75%? |
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| Schramm |
from what I've figured it means the amount of load they are allowed to carry, during the seasons posted. So a tractor-trailer can only be filled to %75 capacity, which ya is alot more than a cube van weighs, but the weight is spread out better.
I'm not sure, but thats what I've always assumed |
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| bw54867 |
while on the topic
whats a jack brake? whats an air brake? |
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| Schramm |
haha and how do engine retarder brakes work? :P
comon truckers! |
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| Invalid Zero |
Jake brake is a brand of engine brake that's popular enough that they are referred to as "Jake" brakes.
They work by reducing lift on the exhaust valves, which makes the engine harder to turn acting as a compression brake. Kind of like reverse Vtec. :p
EDIT: Whoops, I had it wrong.
http://en.wikipedia.org/wiki/Jake_brake
"A compression release engine brake uses an extra lobe on the camshaft to open a second exhaust valve at the top of the compression stroke."
Air brake are just that. Brakes actuated by compressed air, whereas your car uses hydraulic pressure to stop. |
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| Stainless |
quote:
Originally posted by Schramm
from what I've figured it means the amount of load they are allowed to carry, during the seasons posted. So a tractor-trailer can only be filled to %75 capacity, which ya is alot more than a cube van weighs, but the weight is spread out better.
I'm not sure, but thats what I've always assumed
That's exactly what it is. I have a maximum axle allowance of 46,500 kg on a normal highway. When there is a 75% road ban on, I can only weigh 75% (34,875 kg).
One stretch of banned road can ruin a day. There have been a few times where I've added 40 kms to a trip just because there is a ban on a few kms of road due to the detour. The fines for being overweight are massive, calculated per km. |
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| Seks |
quote:
Originally posted by Stainless
That's exactly what it is. I have a maximum axle allowance of 46,500 kg on a normal highway. When there is a 75% road ban on, I can only weigh 75% (34,875 kg).
One stretch of banned road can ruin a day. There have been a few times where I've added 40 kms to a trip just because there is a ban on a few kms of road due to the detour. The fines for being overweight are massive, calculated per km.
Since the sign that I saw specified that the ban is effective starting March, I am assuming it has something to do with trying to avoid creating unnecessary potholes during the spring thaw period? |
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| THUD |
I love the Jake on my truck it's strong enough that I don't hardly have to use my brakes, that said on icy road it can make the engine return to idle while at hiway speedsISH.
It's spools up the turbo to a nice pitch and cools it down and the motor temps drop a bit to, it can really help in the mountain's or hills...or traffic.
Road bans are popping up early cause of this current melt and believe me the frost heaves are starting to make me barf and wreck my back, on some roads a 50% max basically means your screwed cause of soft ground.
My tires will rip up the ground or I sink and the wash board can get ridiculas on paved or gravel roads so instead of ripping up the roads we jsut carry less and rip them up slightly less. |
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| aarrgghh |
quote:
Originally posted by Seks
Since the sign that I saw specified that the ban is effective starting March, I am assuming it has something to do with trying to avoid creating unnecessary potholes during the spring thaw period?
Also to prevent the water logged and therefore soft 'ground' under the road from being compressed and creating deep ruts in the pavement. That's why its typically active during spring as the snow melts. A good road is all in the ground prep. |
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| wireless |
so i always assumed this is why
but why did the government or w.e let those deep .. trenches happen on the right lane of calgary trail right by 23rd ave. they can almost affect your steering and im positive some lowered car has probably bottomed out on them
theyr ridiculous |
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| Invalid Zero |
| That's because of the sheer volume of heavy traffic. |
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| Psi |
quote:
Originally posted by Invalid Zero
Jake brake is a brand of engine brake that's popular enough that they are referred to as "Jake" brakes.
They work by reducing lift on the exhaust valves, which makes the engine harder to turn acting as a compression brake. Kind of like reverse Vtec. :p
EDIT: Whoops, I had it wrong.
http://en.wikipedia.org/wiki/Jake_brake
"A compression release engine brake uses an extra lobe on the camshaft to open a second exhaust valve at the top of the compression stroke."
Air brake are just that. Brakes actuated by compressed air, whereas your car uses hydraulic pressure to stop.
There usually isn't an extra lobe on the camshaft for a jake brake because not all diesel engines use them. At least not on any of the HD engines I have worked on. The jake or pac brake heads sit on top of the engine head and when applied they run off the the engines existing exhaust valves and exhaust lobes. 1-2-3 settings apply either 2 cylinders, 4 cylinders or all 6 cylinders depending on how fast you want to slow down.
"they reduce the lift of the exhaust valve", Sort of. All that happens is the jake opens the exhaust valves BTDC on compression stroke. The lift of the exhaust valve would be the the same if the jake was not applied. |
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| Graphicdude |
| Just take a look at Yellowhead and about 142 st and you will see why there are road bans on trucks during certain times of the season. They can really fuck up a road during spring thaw. Its horrible! |
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| The Stig |
I bottom out there! I hate it, and with fat tires, the steering gets yanked all over the place, it's very difficult to slow down, and remaind going straight because of those roads!
Weight bans are fine, it just sucks when you're used to taking 100% load, and now have to do twice as much because t's a 50% ban! More money. |
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| jzz30tt |
Aren't there two differnt types of brakes referred to as engine retarder brakes? Engine brake and Exhaust brake? Pac brake makes an exhaust brake i think.
Or (very likely) i have things mixed up. |
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| Psi |
Jacobs and Pac brake are both engine compression brake's
Im not sure which manuf. make exhaust brakes. |
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| ctt1982 |
the exhaust brake works by blocking off the exhaust which builds pressure as the piston is trying to push the exhaust out. not nearly as effective as an engine brake.
in my truck for example, the turbo pumps up to 30psi of boosted air into the engine which further gets compressed and therefore slows the engine down.
my truck also has the advantage of a really effective traction control that will cut the engine brake when the tires start to slip even the slightest bit:thumbup: |
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