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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: robertglines1 on November 03, 2013, 06:22:27 AM

Title: interstate crusin speed?
Post by: robertglines1 on November 03, 2013, 06:22:27 AM
After reading over years and hearing people with all kinds of buses with all kinds of tires /engines/trans/equipment/ages and everything. I have felt bad about my opinion but here it goes : I.m going to start something: I feel everyone has a comfortable speed and all equipment has a sweet spot.   A comfortable speed is which you can preform safe within your abilities.  The equipment has a safe operating limit and also a sweet spot which it preforms best.     For example:: On my 89Prevost Equipment performance sweet spot was around 68-72 mph on interstate  fuel etc and I felt my driving experience over many years in good traffic conditions that was a reasonable speed.   When things changed I slowed down.   I did drive/operate heavy cranes and equipment for 40yrs including 100ton plus loads.  You don't stop like a bus. I guess when I see people with state of the art bus telling everyone to not keep up with traffic I question my mind set?     Do Note:: My brakes are 1st class or it don't move!     I have had more close calls 60mph on interstate.   Just wonder if I am the only one with this mind set?

Title: Re: interstate crusin speed?
Post by: lostagain on November 03, 2013, 06:31:47 AM
65-70. Depends on conditions. Cool weather, no or tail wind: 70. Hot and/or head wind: 60-65. My bus is really smooth at any speed so that is not a concern. It will go 85 if I ask.


Title: Re: interstate crusin speed?
Post by: luvrbus on November 03, 2013, 06:40:53 AM
On the interstates Bob I did my best to drive the posted speed limit I could always picture a trucker coming at full bore and smacking the hell out of me

 Here in AZ with the speed limit 65 mph in downtown Phoenix you will get run over if not driving the speed limit or over in most cases

Title: Re: interstate crusin speed?
Post by: robertglines1 on November 03, 2013, 06:48:12 AM
I hate that right lane in cities or around merging traffic---always a speed demons merging or someone cutting you off then hitting brakes.    I hear you about the charging semi in the rear!!!   

Title: Re: interstate crusin speed?
Post by: Dave5Cs on November 03, 2013, 06:54:55 AM
We drive the speed limit which in most cases is 65 MPH on freeways. Around town I have to slow down at times because it wants to go faster and don't realize it is sometimes!... ;D


Title: Re: interstate crusin speed?
Post by: bobofthenorth on November 03, 2013, 06:59:03 AM
I generally try to fit in with the traffic flow.  Note that does NOT always match the speed limit.  On some highways traffic routinely moves 10 MPH above or below the posted limit.  I've had periods where I tried to drive for economy - ie. self-imposed 55 limit - fortunately I have grown out of that nonsense.  I agree with what Bob said - there's plenty of danger from slow moving vehicles - I'm not sure they are more dangerous than fast moving vehicles but they're dangerous nonetheless.

I try not to be stuck in the curb lane because in too many locations that will quickly get you sucked off into an exit but I balance that concern against always knowing where my escape route is.  Sometimes the escape is the ditch and sometimes it is an adjoining lane.  Nothing bothers me more than heavy traffic moving at high speed where you are trapped in an inner lane with no escape to either side.  I try to leave a large buffer in front of me but of course that leaves space for idiots to cut into.  I just tell myself that they are my crumple zone and that makes it much easier to let them cut me off.

Title: Re: interstate crusin speed?
Post by: luvrbus on November 03, 2013, 07:00:08 AM
DPS will pull you over here and tell you to pick it up or turn on the 4 ways I am all ways in the middle lane driving in town our freeways are marked good so you have plenty of time to move over before your exit is needed Houston and Dallas it's bitch there not much marking in advance I 35 moving on to US 75 in Dallas is a nightmare to me

Title: Re: interstate crusin speed?
Post by: Ed Hackenbruch on November 03, 2013, 07:05:35 AM
 I seem to get my best mpg at 70-72.  I try to stay out of the right lane going thru cities if possible.  55 is a bad speed for me as 57 is where the tranny wants to shift, so i am either high rpms in 3rd or lugging it in 4th.

Title: Re: interstate crusin speed?
Post by: John316 on November 03, 2013, 07:07:04 AM
We hammer down and roll when we can, depending on the speedlimit. In city's we run with the traffic. The only time that I can remember running slower than the speedlimit was in Texas the speedlimit was 80. We have no problem at all running at least 80. Problem that day was the wind. It was crazy windy, and I just didn't feel it was safe to run over 80. That day was 70.....

Title: Re: interstate crusin speed?
Post by: lostagain on November 03, 2013, 08:00:48 AM
A good friend of mine (ex Brewster driver) drive the Red Arrow from Edmonton to Calgary every day. It is a luxury regular schedule service that runs several times a day, catering to business people in suits with lap tops and brief cases. Late model Prevost H3-45 with wide seats, wifi, snacks, drinks, the whole bit. 3 hour drive, competes with the air lines. The speed limit on the freeway is 110 km/h (70 mph). The traffic is usually heavy, bumper to bumper and runs 120 to 130. He sets his cruise control at 113 km/h. He feels good at that. Traffic gets by him nicely, and he rarely has anybody in front of him bothering him. He is tracked by dispatch every second of the way by GPS. He is allowed I think he said 125 three times per trip for passing. Cushy job, no luggage or freight, would be boring for me, but he likes it. Well paid.


Title: Re: interstate crusin speed?
Post by: belfert on November 03, 2013, 08:06:06 AM
I always run at 65 to 67 MPH for fuel economy.  The bus can easily run 70 to 75 MPH, but I'm sure it cuts the MPG.  I have no idea if the bus could run 80 MPH consistently and no desire to find out.  Most of my bus trips have been I80 out west so there is little traffic except in Omaha and Salt Lake City.  At 67 MPH we pass as many semis as semis that pass us.

I have gone southeast a few times and the speed limits are generally less.  I still run at 65 MPH which is often the speed limit for trucks/rvs in that area of the country.  In Chicago the speed limit is 55 MPH last I went that way and even 75 MPH can have all kinds of cars passing you.

Title: Re: interstate crusin speed?
Post by: TomC on November 03, 2013, 08:22:26 AM
At least with big rig trucks, the rule of thumb is-for every mile per hour over 55mph to 65mph you loose .1mpg. For every mile per hour over 65mph to 75mph you loose 1.5mpg. So the difference between 55mph and 75mph can be 2.5mpg! Most of my truck companies are limiting their trucks to 65mph for fuel mileage. I believe all large commercial vehicles should be governed to 65mph-course that doesn't include private motorhomes. Good luck, TomC

Title: Re: interstate crusin speed?
Post by: luvrbus on November 03, 2013, 08:57:23 AM
These speed limit post always amuse me back in the 70's and 80's when were ordered to drive 55 mph tops to save fuel no one wanted to drive 55 now we are older and wiser with speed limits up to 85mph we want to drive 55 and 60 mph to save fuel  ;D go figure 

Title: Re: interstate crusin speed?
Post by: bevans6 on November 03, 2013, 10:26:00 AM
Trucks are limited to 105 kph with electronic governors in several provinces up here, and seem to run that speed even when they are allowed to go 110 kph by the speed limit.  I just run with the trucks in the slow lane.  Except for the logging trucks.  If they have a decent hill they'll be doing around 90 mph by the bottom of it.  And back to 50 mph on the upside of the next hill.  They are crazy...


Title: Re: interstate crusin speed?
Post by: belfert on November 03, 2013, 11:02:18 AM
Fuel wasn't $4 a gallon back when speed limits were 55 MPH.  If fuel was back to even $1.50 a gallon I would probably drive at the 75 MPH speed limit.

Title: Re: interstate crusin speed?
Post by: lostagain on November 03, 2013, 11:38:39 AM
Jeremy, correct me if I am wrong, but aren't all transport trucks and buses limited to 90 km/h (55mph) all over Europe? Is it more for safety, or economy?


Title: 60 MPH At 1500 RPM In 10th Gear
Post by: HB of CJ on November 03, 2013, 12:57:20 PM
1500 RPM seemed to be the sweet spot with the Big Cam Cummins pancake engine.  Since the Crown Supercoach only got to go on just a handful of meaningful road trips, the remembered fuel mileage is hazzy, but probably was between 10 and 11 mpg.  Crowns are kinda aerodynamic....up to a certain speed.  HB of CJ (old coot)

Title: Re: interstate crusin speed?
Post by: white-eagle on November 03, 2013, 01:20:24 PM
my sweet spot is around 70.  much slower and the rpms are too low for the next hill.  middle lane in towns to avoid the constant move out of the way of entering cars.  i try to avoid the "crumple zone" Bob otn mentioned by backing off from the idiots when i can, and like he said, i look for my best option direction, just in case.
in the flat states, 65 can become 75 pretty quick if i'm not watching close enough.  i try to pay attention because Fran gets upset if i have to brake and it dumps plants, etc.

Title: Re: interstate crusin speed?
Post by: Oonrahnjay on November 03, 2013, 02:45:52 PM
  ...  logging trucks.   They are crazy... 

     That seems to be true everywhere.   

Title: Re: interstate crusin speed?
Post by: roadrunnertex on November 03, 2013, 02:57:31 PM
My P8M4905A with a 8V/71 & V730 transmission does real well at 60 to 65 mph on the interstates in Texas and the Southeast.
6 to 6.5 mpg on the last trip with R.J.Long as the driver and I the co-pilot.
It's to bad fuel is almost $4.00 per gallon but that is the way it's going to be for us diesel powered folks.
Back many years ago when Greyhound had real buses and real bus drivers who use to drive the Silversides and the PD4104's and the PD4501 Scenicruisers. My dad was driving for Greyhound and there were no interstates in Florida he used to drive 60-65 mph and do just fine.
To this day I can still hear him say keep it between 60&65 MPH son and you will do just fine.
I wish he was still around to see how the industry has changed.

Title: Re: interstate crusin speed?
Post by: RJ on November 03, 2013, 09:54:53 PM
My P8M4905A with a 8V/71 & V730 transmission does real well at 60 to 65 mph on the interstates in Texas and the Southeast.

What John forgot to mention here is that we were fighting a cross-headwind the entire trip from TX to the Blytheville gathering, where we fueled before we left.  (And had a GREAT time, too!)

Calm weather for the trip back to TX, so mileage might be better, we'll see when the numbers come in.

4905s are in "the sweet spot" for ride, handling, noise and comfort at about 65 +/- a couple mph.

FWIW & HTH. . .


Title: Re: interstate crusin speed?
Post by: Mike in GA on November 04, 2013, 01:54:37 AM
Ultimately we must do what we are personally comfortable doing, since few of our rigs are similar and our ages and driving abilities vary.
     For me, I like to run about 2000-2100 on the tach, the bus's sweet spot, which on the flat is 62-64 mph, no headwind.
     I prefer to travel in the right lane, unless in a city with lots of on-ramps. Here are my reasons:
1. I like having the breakdown lane immediately available if I should develop a sudden mechanical problem;
2. I can jump into the breakdown lane if someone stops short in front of me. And I have used it, in the blink of an eye;
3. My speeds are slower than most, and I don't want to clog the middle or the passing lanes, hold up other motorists or force some right-lane passing;
4. In my advanced age (69 two more days) I confess that my planned exit ramp occasionally sneaks up on me, and I can get to it easily from the right-most lane. (I realize that this rarely happens to other readers!).
     An old professional driver in our Bus Nuts group who has been full timing for 20 years encouraged me to start busin' by using the right hand lane, for safety and to allow myself to get used to driving a big rig with tow car, whose bus cannot and will not stop as quickly as the cars I was used to. I followed his advice and haven't changed much after 13 years of fun.
     Just my way. YMMV.
Mike in GA

Title: Re: interstate crusin speed?
Post by: Jon on November 04, 2013, 04:21:10 AM
I drive slow. I expect folks to nod their heads and tell me I am dangerous, a rolling road block, and any other descriptors to let me know I am a road hazard. But the reality for me is my coach is a RECREATION VEHICLE. I'm a 62 MPH driver in states whose typical posted highway speeds are either 65 or 70.

During a typical day of driving I will pass several vehicles per hour, but for the most part I will be passed by everyone else. I will pass certain company trucks whose speeds are likely governed. I will pass motorhomes and RVers with trailers and the occasional car. But typically I can set my cruise control and just relax knowing I am not going to have to be on and off cruise control because I am running up on the back of vehicles and need a lane change. For me driving like this is as relaxing as sitting in the living room chair.

My biggest concern is not how fast I come up on someone, but how to prevent the idiots from getting run into by me. Like everyone else I have the same fools pull in too close and then hit the brakes because they need to get off at the exit, or who don't know how to merge due to lane closures, or who just suddenly have a rain drop hit the windshield.

At that speed my Series 60 is turning 1500. most hills won't affect me, but if I sense a grade that might prove an issue I just downshift prior to getting there so I don't lose speed.

I ran quite a few miles with a friend whose preferred speed was 70. The bus was happy there also, but I had to change lanes a lot more often because I was passing a lot more vehicles, I was on the brakes more, and I was on and off the cruise control. Driving was less relaxing and not a lot of fun. But worse, I know the stopping distances required to save the lives of the idiots increased dramatically so I was never enjoying the ride.

Title: Re: interstate crusin speed?
Post by: Jeremy on November 04, 2013, 04:42:08 AM
Jeremy, correct me if I am wrong, but aren't all transport trucks and buses limited to 90 km/h (55mph) all over Europe? Is it more for safety, or economy?


Sorry, only just seen this question. This is one of things where, despite laws supposedly being homogenized all across Europe, each country still manages to keep the same speed limits it's always had (and Britain, speeds and distances on roadsigns are still shown in imperial, despite the fact that the country went metric 50 years ago).

In Britain the speed limit for trucks on multi-lane roads is 60mph and for buses it is 70mph. On single-lane roads it is 50mph and 60mph respectively. Buses and cars have the same limit here, and for example buses are allowed in the third lane on motorways, which trucks are not. Cars generally run at around 85mph on the motorway here, which is considered acceptable, and it used to be that coaches did too - but there was a series of accidents a few years ago which put a lot of bad publicity onto the coach industry and they rarely break the limits now (and, as I said in another thread, my own bus has a speed limiter). Until earlier this year (when the environmentalists got in the way) the Government was proposing 85mph as the new limit for UK motorways, but I imagine that if that did ever happen that they would introduce a lower limit for buses (and I'm sure that would be the correct thing to do).

I'm not sure about limits in other countries but I think the 90kph for trucks that you mentioned is widespread because a lot of foreign trucks that you see here have '90' symbols on the back. But whether that applies to buses and coaches I'm not sure. I do know from driving in France for instance that their motorway signs have two speed limits posted, one for when the road is dry and one for when it is wet - which has always seemed incredibly sensible to me


Title: Re: interstate crusin speed?
Post by: robertglines1 on November 04, 2013, 05:48:34 AM
To be clear:: I have always believed one should drive their own race!  Drive to their abilities and equipment.  I just felt that the general attitude presented on the boards is/was that if you didn't drive 55 to 60 in the right hand lane ==your doing it wrong.  Not saying anyone  change!   Stay safe==  will be proud to run with you at any speed.   Not past my limit! ? unknown in new ride?   Bob

Title: Re: interstate crusin speed?
Post by: Bill B /bus on November 05, 2013, 04:42:01 PM
First bus was a PD4108. Sweet spot was 72 to 75 MPH. Mileage was 8 to 8.3 MPG. That was a little faster than I wanted to run. Changed tires to 11/22.5. Sweet spot moved to 66 to 70 MPH. Mileage improved to 8.5+ MPG.

Second bus is an MCI102A3 with a Series 50 and an HT70 transmission with a .75 overdrive. Happy spot is around 62-67 MPH. Fuel mileage is running around 8.5 to 9 MPG. Last tank was 9.6 MPG. So I quite happily drive in 62-65 MPH range. Going that speed north on I81 I was with traffic in the right lane and occasionally passing trucks running 60 MPH.

I will agree that sometimes traffic demands a higher or lower speed to prevent being the rock in the road or trying to force a way through. The Northeast is an example of a higher speed required to flow with the traffic.

Since we try to stay off the Interstate as much as possible our speed works.


Title: Re: interstate crusin speed?
Post by: wg4t50 on November 05, 2013, 04:55:12 PM
The most aerodynamic bus I have any experience with is the old Senicruiser, my MC7 needed slight fuel to go down a specific moutain, why the Senecrusier needed use of brakes on same mountain. That was an eye opener for me.  He never got good fuel mileage due to running a 8V-92 with 150 injectors RTO910, 4.10, 10R22.5 and 2650 RPM and driving about 80 mph most time, yes he lost license many times, but could not put it together. After one short trip with him, I never allowed a repeat, yes there is such a thing as CRAZY.