This will get some people stirred up

[Old Scool Bus]

I never said anything even remotely close to Pee is gray water & my panties are not in a wad, the string is however up my but 

This bus was owned (bought new) and maintained by the city of Denver and has spent a large amount of it's life with the tag chained up. I'm sure that if that were an issue it would have been one by now.

[RJ]

OSB -

I'm curious. . . how many miles have you driven buses in revenue service, and what makes/models?

(Hang in there, there's a method to my madness!)

[niles500]

(Prefaced: w/o modification) It seems to me that it'll be just fine until the stress cracks are evident - right before the frame shears and drops the engine cradle on the tarmac - but WTH I'm a protaganist - - FWIW

[Gary '79 5C]

Since I am of the unwashed here with my 5C (sans tags), How much does the tag contribute to the braking of the coach ?

If removed, would that leave someone open to a zealous lawyer if in an accident ?  I never thought in this manner when living in West Virginia, 33yrs in NJ things are different... But I digress.

I know some coaches were delivered without tags, (entertainer? I forget the name), possibly because their design weights were lower ?

Gary

[johns4104s]

Last week I had a tag tire blow. With the movement the coach did I thought it was a front tire, I would thinkthe bus would be had to control  leaving the drive in its original.

The 4905 has two bay wheels that drop, and the drive axle is much futher back? John Ed you could check on Google for us?

John

[Dreamscape]

I'm going to throw my 2 cents into the mix.

If your coach was designed for three axles, I'd keep it that way. There has to be a logical reason for doing so, weight transfer, load bearing etc. Two axle coaches were designed for the intended purpose, a lighter load and proper weight distribution and transfer of load.

You say it's OK because it's been that way by hanging it on chains for a long period of time. That's much different than putting on thousands of miles and hoping the engine cradle stays intact.

This is one are that thinking outside of the box could be a disaster, and I like thinking outside the box, just not reinventing it.

I am by no means an engineer, just trying to be logical.

Paul

[bryanhes]

Just a question about Tags. I know that most 40' busses will haul in the range of 47-50 passengers on average. And in most cases I would assume they bring along about the same amount of luggage. With that being said wouldn't most likely they all have close to the same load capacity? I guess it is in part placement of the axles as to whether or not they can be removed? If the tag is a bogie like on my 4905 that I removed or on say an MCI where it is an actual wieght bearing tag assisting in support of the cradle. Some of the 4905's did not even come with a tag. But there again I guess it is placement of axle distributing the weight?

If weight load is close to the same would it not work to move the axle back to a closer position of maybe where the 4905 is placed?

Just thinking out loud 

Bryan

[bevans6]

Just doing some thinking and doodling about this.  Here is what I have come up with.  It seems reasonable to me, but I could be totally wrong...

When the bus is stretched from 35' like a MC-5 to 40' like a MC-8, the wheel base only increases by 2 feet.  That means that the additional weight of bus, and the stuff like engines and cooling systems, all of that, is cantilevered out an additional 3 feet.  That weight is supposed to be supported by the tag axle.  The tag does two things, it supports the weight, and since the fulcrum of the leverage of that weight is the drive axle, it transfers weight up to the front of the bus.  All fine so far.  With the tags chained up, you have the worst situation weight distribution-wise, you have none of the support and all of the weight of the tags.  Just removing the tags, you make things better by removing the weight load behind the axle, that will transfer some weight forward and reduce the weight on the drive axle.  

If you move the drive axle back, you will improve the weight distribution back towards what it would be if the tags were in play.  You will increase the turning radius of the bus.  You may reduce the cantilever loads of the engine and the rear of the bus relative to the drive axle - but that will depend on how and where you engineer the replacement of the air beams and how they tie in to the structure of the bus.  The air beams are what actually holds the bus up, obviously.  I think  engineering wise it would be simpler to engineer a truss to transfer load back towards the air-bag supports for the tag axle to let the drive axle bags and air beam transfer support to the tag axle air bag mount.  That will restore any strength required to support the back of the bus.  Doing weight load calculations will let you predict with some accuracy exactly what removing the tag will actually do.   Example - wheel base is 285" between the drive and steer axles.  Tag axle is 60" behind the drive axle (guess).  If you remove 1500 lbs (guess as to the total weight of the tag assembly currently chained up and not helping at all) then you will transfer 315 lbs back towards the steer axle.  60/285 is 0.21, and 1500 * 0.21 is 315.  If you were to remove the AC compressor, and it was 10 feet behind the drive axle and weighed 250 lbs, then you would transfer 105 lbs towards the steer axle.

This will have a similar effect of what the tags are supposed to do, which is support the back of the bus and transfer  weight forward.  If the tags were down and carrying 5,000 lbs at 60" behind the drive axle, they would transfer around 1,000 lbs towards the front.  

I think this is how it would work out, anyway.  Feel free to debunk!  

Brian

[muddog16]

I rarely get involved in these, but this is serious stuff!  I agree with Paul, when engineering these buses, smarter people than myself spent many hours designing something that was safe, after 20 plus years the design must have worked!  I've only put the miles on my bus driving it home....being new I decided to lift the tags (to save tire wear), until it started raining......the bus was what I call darty (quick side to side movement), I actually thought I had a flat tire.......after stopping and inspecting I didn't find any tire problems.  Back on the road I put the tag down and the dartyness immediately stopped.....!  Look at the weight distribution on buses all three axles are there for a purpose.  They didn't design this to use extra tires up for Goodyear or Firestone.........!   It's your bus.....innovation is applauded, but sometimes you just have to shake your head !  If if fails........some shyster lawyer will love picking through the pieces to see if you are going to pay for his kids education or buy that new Mercedes for his girlfriend!

[cody]

I don't understand metal and I've made that perfectly clear but I'm also agreeing that the flavor of the board has changed over the past couple of years, I came here from RV.Newt because of they were so judgemental and even had the amazing ability to tell if something was overloaded by seeing it from a distance, this board was different because a person could propose a radical idea and people would say, wow thats differrent, I wonder how we could do that, now it's don't change the engineering or the sky will fall lol, I don't know how many times I read that phrase about tell me what roads you'll be on so I can take different ones.  Here we know what the problems are, 1. is different loading of the axles, ok the cure could be moving the drives back, 2. the problem is the engine cradle, cure could be reinforcing it so that with the new placement of the drives it's strong, fact is, those cradles break with all the axles in place, so they need reinforcing sometimes anyway.  Everyone has a different idea, lets get back to the shade tree thinking and maybe think of some radical changes that would help instead of condemning it, we've even got a guy here that cut a scenic in half and lengthened it, then glued it all back together, and a guy thats making a semi truck into a box camper, if someone went over to rv.net and asked if they could glue the siding on a bus, they would still be laughing over there, I'm with you schoolie, just because it's different doesn't mean it's wrong, just needs to be done right to be safe.

[luvrbus]

Just my 2 cents the 4905 the boggie were a option to meet the axle weight laws in different states, Lot of 40ft buses without tags or boggies but they were made that way from the factory Eagle had several models.
As far a removing a tag to me that would be a no/ no we have a guy in the Eagle club that removed his boggie on a 05 Eagle to get another baggage bay now he is trying to figure out how to reinstall it causes him problems.
The Denver buses the tags were raised for turning and the snow but do it your way it is the best way to live and learn.
FWIW I believe you will find out the engineers at the manufacture knew what they were doing even if some are a little flaky LOL but to put more stress on a suspension system that was designed for 3 axles and no frame that I have problem with

good luck

[kyle4501]

Nothing wrong with thinking outside the box, or even venturing outside once in a while.  
-BUT- belligerence towards the less than enthusiastic responses to questions concerning "new" ideas - - - Well lets say that ain't the way to build credibility, win friends, or influence people.  

I'd suggest a class or 2 in vehicle dynamics before you dive into this modification. At least then you'd have an idea of the complexities involved vs limited seat of the pants experience.
(The 4905 was designed as a 2 axle bus. The retractable bogie was added to satisfy state laws requiring 3 axles for the weight. The MCI8 was designed as a 3 axle bus. The GM buses were the lightest coaches built, the MCI's were heavier. . . . )

Sure, you can remove the tag - BUT, what are the effects?

Sure, you can move the drive axle, but have you given any real consideration as to how the bus structure is affected?
A longer wheel base = a longer turning radius, & that isn't something most want when they find themselves in close quarters. . . .
BTW, if one needs to have the weight distribution explained, maybe their engineering abilities ain't up to the task of changing the structure. . . .  


The reason for all the negativity to the unorthodox things that get proposed is because there have been enough half started conversions that were abandoned because the difficulties kept adding up & we don't want to see more. If one tosses out an idea only to hear negative feedback, that should be a clue that it ain't as good an idea as first thought. - That's not to say don't do it, but rather 'approach with caution'.

Copping an attitude will reduce the level of respect received from others.

What kind of friends would encourage someone to do something without warning of the known/ perceived risks.



If all you want is 'atta boys', then stick with talking to the dude in the mirror.
If you want insight about a path you're considering - ask away, just don't be surprised that the path may contain more pot-holes that you'd like. . . .

[Len Silva]

This community is extremely tolerant, they even put up with me.  The easiest way to challenge that tolerance is to ask for advice, then put down the advice giver because it wasn't what you wanted to hear.  The very subject line of your post indicates that that may have been your goal all along.

So, my advice; go for it.  I think it's a great idea.  Take lots of pictures and let us know how it works out.l

Len

[gumpy]

I was going to abstain from this because it was obvious you didn't want to hear what I had to say, but, well, you know how it is...

It seems from the information you've posted here that you have nearly zero experience with highway coaches and maybe even less experience with logical thought processes, critical thinking, and maintaining interpersonal relationships. But then again, I don't know you. I'm only going on what I read here.

I have what I would consider more experience cutting up an MCI than your average bear, and probably more seat-of-the-pants engineering than most, and I pride myself for my above average ability to think outside the box and try things others said couldn't
be done. I grew up with a torch in one hand and a welder in the other. I like to think my greatest ability is to know my limitations.
And yes, I'm one of those guys who can look at it from a distance and tell you it's overloaded.    But that really has no
bearing on this thread.

I pretty much agree with what everyone else has said here, especially Kyle and Len and Cliff. I don't have any helpful or optimistic
advice for you because frankly, I think it's a bad idea. But hey, you've chopped a motorcycle or two. A bus is only a little different,
and a bit larger, so I say go for it. Damn the torpedoes! To hell with the engineers (after all, what do they know, right?)

Take the torch to that sucker and create your dream coach. Take lots of photos and show us all how it goes. I encourage you
to be diligent with the documentation. If you succeed, maybe we can learn something. We'll even let you gloat a little. If you
fail (and are still alive), maybe we can learn something.

Bus conversions are hard. They take a lot of time and money. Personally, I think it would he a heck of a lot easier to simply buy a 2 axle 40-ft coach to begin with and do your conversion on that. But, what do I know?

That's not really what you wanted to hear, but the wonderful thing about this hobby is that you can do it your way, and be 100% responsible for you decisions, actions, and final results.... right or wrong!

[cody]

You guys are absolutely right, I forgot who I was dealing with, I defer to your superior knowledge of all things mechanical, as I stated in the beginning I don't understand metal and I appreciate the crew here reminding me, I gave up on the idea of winning friends back in high school but I happen to know of an eagle that is sporting a cat engine, took some  engineering to do it but seems to work, I know of a bus that was split lengthwise and widened, I know of a bus that has no rivits and the door is even on what a lot of people would think is backwards, I felt sorry for a guy that talked about putting slides on his prevo, (that prevo was at BK's and the slides work just fine, wasn't his first rodeo with them).  I'll get off my soapbox now, for those that have pmmed me and asked, yes, libby is still in ICU but she is expected to make it ok.