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Re: How fast is too fast"

Reply #1 –
Yahoo Message Number: 88172
Older Magna w/no tag. This is why I buy Michelins and why you need to replace every 7 years, especially on the front.

Rich 2002 Magna

Re: How fast is too fast"

Reply #2 –
Yahoo Message Number: 88177
My home state is Utah, so this was all over the local news.
It is a very sad accident with devastating results - a family losing both parents on the first day of their trip to Disneyland.

I always look at these accidents and try to put myself in the same situation, wondering what one could do to change the outcome. Some details about the accident do seem strange. The local St George newspaper has much better coverage, including some video of the aftermath.

Photo Gallery Here
Video News Story
The highway patrolman was quoted:

Re: How fast is too fast"

Reply #3 –
Yahoo Message Number: 88179
Very sad.....prayers for the family.

It is a 99 Magna. Had one almost like it for 8 1/2 years.

Tammy T

2006 Affinity 6611

Re: How fast is too fast"

Reply #4 –
Yahoo Message Number: 88180
The thread on this topic was shut down over on Open Roads Forum after the moderator thought some of the speculation about what happened in this sad accident was insensitive. Horrible to hear a family lost two members.
While maintenance may or may not have been an issue, it should be a reminder to all of us to check the condition of our tires, including tire pressures.

Per

95 Affinity

Re: How fast is too fast"

Reply #5 –
Yahoo Message Number: 88196
My wife and I recently took an RV driving course at LazyDays in Tucson. First to speed the instructor stated that 55 to 62 is the sweet spot mileage wise for a diesel pusher. Second he stated that LazyDays did a real world experiment where two identical coaches travelled from Florida to San Francisco. One went 55 the whole way and the other whatever the speed limit was up to 75. At the end of the test the coach going 55 got to San Francisco first because the faster coach required 3 additional fuel stops. That is a lot of wasted money to at the end of the day lose time. As to a blow-out and I never knew this. If a tire blows out you MUST immediately accelerate in order to get control of the coach and only then slow down in a controlled fashion. LazyDays has a Dept. Of Transportation video posted demonstrating why this is so. The idea of accelerating after a blow-out is counterintuitive at least to me but the video and explanation are sound and I think about this every time I drive.
Bottom line is slow down and enjoy the trip that is what this life-style is all about and then do every thing you can to be safe. As our instructor said, "Don't let anyone or any situation cause you to endanger yourself or your coach. Better laughed or even cursed at than mourned for". These were wise words I had never heard before and I past them on. Take care all and safe travels.

Al Kirkendall
2009 Veranda 300
Serial # 52197

Re: How fast is too fast"

Reply #6 –
Yahoo Message Number: 88201
55 MPH is too slow for us. Not only because it takes forever to get anywhere, but also the coach will stay in 5th gear most of the time, negating any fuel savings. Sweet spot is at 65 MPH, which is at max HP. If not in a hurry, we cruise about 62 MPH. We run 8-9 MPG barring headwinds or hilly terrain.

Per Korslund
95 Affinity 5259

Re: How fast is too fast"

Reply #7 –
Yahoo Message Number: 88202
Ditto to the sweet spot being 62 MPH..
Just 1-2 miles an hour faster and the MPG crashes.

Russ

05 Intrigue
11883

Re: How fast is too fast"

Reply #8 –
Yahoo Message Number: 88203
How do you arrive at the sweet spot? Is it a function of the RPM where maximum torque is achieved...and not exceeding that RPM? I haven't had my coach long enough to test cause and affect. I think my Cummins 400 ISL has peak torque of 1200 ft lbs at 1300 rpm. So would my sweet spot be 1300 rpm?

Dan

2006 Allure with tag

#31344
From: "russg@..."

Sender: Country-Coach-Owners@yahoogroups.com
Date: Thu, 30 May 2013 11:46:42 -0500
To: Country-Coach-Owners@yahoogroups.com

ReplyTo: Country-Coach-Owners@yahoogroups.com Subject: RE: [Country-Coach-Owners] Re: How fast is too fast"

Ditto to the sweet spot being 62 MPH..
Just 1-2 miles an hour faster and the MPG crashes.

Russ

05 Intrigue
11883

Re: How fast is too fast"

Reply #9 –
Yahoo Message Number: 88207
Dan, the sweet spot was found via recorded fuel consumption on long legs.. using cruise control.
It was mirrored on the Silverleaf, (fuel consumption rates) as well.

After a while one can feel it in the seat of one's pants.
Drag coefficient and torque / RPM (combined) is hard to quantify with our coaches.

But the numbers do show up at the end of the day..

Russ

05 Intrigue
11883

._,___

Re: How fast is too fast"

Reply #10 –
Yahoo Message Number: 88208
Hi Dan,

Coaches can be a bit different between years and models, based upon different engines (CAT vs Cummins, or even 2004 ISL370 vs newer ISL425, etc.). Different years could also have different gearing in the rear ends too.
If you have Silverleaf, set it to display the rolling MPG. Take sometime to call Cummins with your coaches engine number, and ask them for the specific RPM to Torque peak, and RPM to HP peak, ranges.
Then over a few full tanks, watch your RPM to Torque and HP, and get a feel for the rolling MPG at different RPM's on a flat highway.
We find out ISL370, returns the best MPG at also just about 62MPG. But we find for hill climbing, we bump up the RPM's to and it can hold the grade a bit better. We loaf along at about 1650RPM at 62MPH, then climb to between 1850-2000RPM for hill climbing, dropping gears as needed.
One other side comment on the speeding up with a blowout to retain control comment. I think this was for steer wheel blowouts only (could be wrong). For rear blow outs, just ease off the gas and coast to the side of the road, avoid braking if you can. That is how I understand the blowout driving strategy. If front, and you do punch it to get control, then the same thing, ease off on the gas, and coast without braking if you can.

Best to all,
Smitty

04 Allure 31017 40' Tag
04 Allure Sold to a nice new owner! Now enjoying a 07 Magna Rembrandt 45' ISX600 #6775
"We're ONDROAD for THEJRNY!" (Toad and Coach license plates, say Hi if you see us!)

Re: How fast is too fast"

Reply #11 –
Yahoo Message Number: 88209
For me, the sweet spot is where the engine feels most comfortable, and has nothing to do with mileage. For our engine, that is at the max HP point--at 1,600 RPM or 65 MPH in 6th gear. Max torque is much lower at 1,200 RPM.

Per

95 Affinity

Re: How fast is too fast"

Reply #12 –
Yahoo Message Number: 88215
I have to agree, but have found by dropping weight, carrying less water and stuff, pulling less, a smaller CR-v, that I can now travel at 68 and get appox the same Milage as I did at 63. Finding a good tail wind and staying away from headwinds is the most important thing. I mean a hilly road is a hilly road. I do wish I had a flow meter like my CR-v in the coach. Its really an art to save fuel. I'm learning that moderate acceleration to 40 where I get into 4th gear and then moderate acceleration above that works best for the CR-V . I imagine the same to 5 th gear an onto 6th gives the best results for the coach. I know stop and go driving eats fuel, causes the transmission to over heat and frustrates the co-pilot. We were stacked up in city traffic for over an hour the other day due to a motor cycle accident. Seemed like I burned a 1/4 tank of fuel to travel 7 miles.
Here's an illustration. We were driving between Junction Texas and Ozona last week when an 45 ft 08 Intrigue with a Cummins ISM 500 over took us, we were running 67 Into a moderate cross wind. We were playing road side tag and I chose to skip one, so just barley beat him to The Ft Stockton Good Sam park. We got to talking and found out he was averaging about 6.5 mpg to my 8.3 at the time. I realize he weighs 6,000 lbs more than I do and is towing a 1000 lbs more. But I have read reviews of Safari's and others using the ISM that got even better milage than I do staying AROUND 60 to 63 MPH. I realize fuel isn't near the most taxing item on the travel expense list unless your driving straight through over long distances, but, its fun to figure out how to reduce costs. Maybe driving from Three in the morning until 9 or so when there is little wind is an idea for some. I do, however, prefer daylight with the sun above the windshield and not in my eyes. I guess that's why I prefer North and south to east and west. .
TWI 2004 Intrigue 11731

Re: How fast is too fast"

Reply #13 –
Yahoo Message Number: 88217
Thomas I have been asking that question for years, and yours is the first logical answer I have received. North South it is.

I have tried both but never considered your perspective.

How do you get to Miami from San Diego, going North and South?

Bob Wexler
SOB

Re: How fast is too fast"

Reply #14 –
Yahoo Message Number: 88220
We'll I cheat, I go west when the wind isn't blowing and go east, north and South when it is. In this part of the world then wind blow mostly from the west or south west. The only time we get a norther or wind from the east is when its either to cold to travel to the north or just plain nasty when the when blow from the east. When we go to Oregon I wait for a calm day and drive to Tucson, visit friends and then drive North to Phoenix. If I'm on a schedule I then drive north by north west to Las Vegas and Reno. Then I hop over the Sierras to Sacramento. When I'm in a hurry I take I 5 North to Eugene or Portland. On the way back its to Florence then south along the coast to Santa Rosa, my former Home then put up my sail and catch the wind to LODI or I-5 and then South to visit friends. Put up the sail up again and catch the wind from Palm Desert all the way to El Paso. On a good windy day I can make 9.2 mpg at a ground speed of 70 mph. Just like going to Houston or Dallas from El Paso, wait for the Western prevailing wind. Every once in a while I get double crossed. In March going from Houston to Frederickburg I got caught buy a 40 mph Norther, and my milage dropped below 7.0 mpg at 55 to 60 mph on HWY 290. There, I couldn't deploy my sail and tack against the wind; or is it tac?
TWI 2004 Intrigue 11731

Re: How fast is too fast"

Reply #15 –
Yahoo Message Number: 88221
Concerning the St. George accident I have a question. It seems that I've always heard, maybe it was simply a sales pitch, that independent front suspensions provide greater control of the coach if it experiences a catastrophic front tire failure.
Sadly we'll never know all the circumstances of the accident that initiated this thread but I would appreciate the wisdom of this group concerning the safety or danger of alternative suspensions.
We replaced the Good Years on the front at three years with Michelins strictly for personal confidence.

G Brown

2007 Allure 31447

Re: How fast is too fast"

Reply #16 –
Yahoo Message Number: 88223
Dan

My C-9 develops max to torque at 1200 rpm and CAT techs have said torque is more important than hp especially with pulling underload. They have suggested not exceeding 13 to 1400 rpms when trying to pull those long western grades.

Dan 2006 Allure 31348

Re: How fast is too fast"

Reply #17 –
Yahoo Message Number: 88224
Smitty

On my C-9, I was bumping rpms un to around 2000 rpms when pulling long grades and I was generating excessive exhaust temp error codes. I was told to keep the rpms down and concentrate on maximizing torque.

Dan 2006 Allure 31348

Re: How fast is too fast"

Reply #18 –
Yahoo Message Number: 88225
At those low RPM's Cat is famous for then water circulation and cooling fan speed become the issue. So if you see the temps starting to climb shift down as Allison recommends because it needs the temps of the engine to stay with in the transmission limits as the engine and transmission share the same radiator and in some cases an external Hayden supplementary radiator was added for those special occasions when the fan isn't turning at full high. I believe the Affinities and Magnas from 05 and 06 were particularly susceptible to over heating and earlier Magnas with the C-10 also had issues. 05 and 06 Intrigues with C-13 had the problem, too.
TWI 2004 Intrigue 11731

Re: How fast is too fast"

Reply #19 –
Yahoo Message Number: 88228
Issues issues, we all have issues. ISL owners wind their engines up tight, Cat wants their engine to growl. I guess it doesn't matter as long as we get over the hill, with out frying the pistons or burning up the transmission. PS. Sounds like some one from Cat over tuned your C-9 a bit. They can do that, so watch out. A couple Allure owners I know with C-9's had Cat techs at Cat rallies turn up their engines a bit!
TWI 2004 Intrigue 11731

Re: How fast is too fast"

Reply #20 –
Yahoo Message Number: 88229
Hi Dan - Did not know you had a C-9, why I mentioned calling Cummins with your engine number. I would follow the advice of CAT for your specific engine in regards to the sweet spot on RPM for torque and HP.
So many variables between years and models, and sometime within the same year and model with optional engines. (Some 2005 Intrigues came with ISL400's, some were optioned out with Big Cat Blocks, as one example.)
I stand by my suggestion to go play with a few full tanks, and experiment watching the Silverleaf rolling MPG...

Sorry I did not catch that your coach had a C-9.

Have some fun:)!
Smitty

04 Allure 31017 ISL370 Tag
04 Allure Sold to a nice new owner! Now enjoying a 07 Magna Rembrandt 45' ISX600 #6775
"We're ONDROAD for THEJRNY!" (Toad and Coach license plates, say Hi if you see us!)

Re: How fast is too fast"

Reply #21 –
Yahoo Message Number: 88230
Thanks Thomas - Great point that another major variable on MPG is 'total weight'... Agree 100% that less is best for better MPG.
Our toad is a CRV too, and I've always joked that is has never found a small hill it will not downshift for:)! If not careful, our 2007 will easily return low 20's MPG. With a bit of care right foot application, and dropping speeds down to around the 65-67MPH range, very easy to get high 20's on the freeways.
So many things can effect MPG, but one constant is the 'punching of the hole' in the air at highway speeds... Tail winds help:)!

Best to all,
Smitty

04 Allure 31017
04 Allure Sold to a nice new owner! Now enjoying a 07 Magna Rembrandt 45' ISX600 #6775
"We're ONDROAD for THEJRNY!" (Toad and Coach license plates, say Hi if you see us!)

Re: How fast is too fast"

Reply #22 –
Yahoo Message Number: 88231
What about max RPM when descending on the C-9? I have concerns because I have gone to 2380 rpm when using the Pacbrake.

Currently in West Yellowstone, Mt

Buddy Bordes Inspire 360 C-9 51887

Re: How fast is too fast"

Reply #23 –
Yahoo Message Number: 88236
It is a fairly simple matter to do calculations to determine the speed of a vehicle in an accident from skid marks, etc. You can be sure the police have done those. Whether that info will ever be made public is another matter.

Rich 2002 Magna

Re: How fast is too fast"

Reply #24 –
Yahoo Message Number: 88237
The news video I saw, said there were NO skid marks.
That led to speculation about the driver falling asleep or experiencing a medical issue, contributing to the accident.

Bob Wexler
SOB