Re: motorcycle rack

[rv_safetyman]

Kind of got behind on this thread, so this a a bit late.  

Lets talk about the installation of a four stroke.  The extra weight is not all that great.  Often, folks remove the miter box and factory air and that offsets the increased weight.  But the real factor is that the added weight is only slightly further back in the frame.  

I really want to be clear here, the Eagle frame structure design is not marginal.  It will take some fairly decent overloading, as many folks have pointed out.  My big concern is how much the structure is compromised by corrosion and fatigue from years of use.  The second big concern is how much overload is too much.  We have a member of our chapter who had a frame failure.  He hauled a big stacker trailer.  Conversely, we have a member who hauled a fairly large trailer back and forth to Alaska many times and never had a problem.

My second goal here is to point out the impact of leverage - hanging a big load out a significant distance from the axle.  

It is done all the time, but I always feel that these discussions need a perspective that cautions new members to be aware of possible issues.

Jim

[rv_safetyman]

Cody, we were posting at the same time.

You seem to have taken the attitude that we are badmouthing the work done on your bus.  Certainly not the case on my part.

Many of us try to use these threads as a basis for not only addressing the poster's question, but for the benefit of other folks reading the thread.  This is especially true of new folks doing searching of older threads.

I vaguely recall the work that was done on your bus.  At the time, I recall thinking it was well thought out and was of quality workmanship.  

Here is where the rub comes in:  these frames (not just Eagles) were developed over many years based on both engineering (I assume) and lots of first hand experience.  Then we come along and start hacking on that structure.  When we do that, we begin to modify some important structural characteristics.  One of the major characteristics is torsional rigidity.  All of theses buses were made to flex (both longitudinally and torsionally).  When we hack on them, we change the loading distribution of the "system".  

Another way to say that, is that bulking up the structure with lots of reinforcing, can theoretically  cause problems.  It might make the structure so stiff that the loads are not shared properly.  

A structural engineer would pull his hair out if he looked at some of the modifications that folks make to their buses.  

Why do most folks not have problems?  Probably lots of factors.  First, our modifications are not being asked to go a million miles (failures are fatigue related and it takes a ton of cycles to to produce many failures).  Secondly, most of the modifications are probably not sufficient to compromise the original structure to a level that will cause premature problems.

Please, PLEASE, do not take my comments as some sort of challenge to the work you have done and will do in the future. My goal is to let folks know that modifying our beasts should be done with care.

Jim

[Ace]

Wow does reading this thread ever bring back memories if when I started my conversion! Never could do anything right and the replies I mostly got were from wannabee dreamers! Guess what? Everything I did and was advised not to is STILL working as planned!
My advice, forget the many opinions and just get it done or you will find, as you already have seen, yourself in a long winded never ending debate! Only you and your pro welder will know if it's right for you ir not!

[happycamperbrat]

In another forum I asked a question about cutting a hole and reinforcing the frame on my bus. Wow! Two people actually got in a big fight over it and both of them ended up quitting the forum after taking multiple below the belt type jabs at eachother online. Modification of the basic body design does not seem to go over well for many people, no matter the bus or experience/qualifications involved. The old song goes something like "you cant please all the people all the time, so you got to please yourself"

[Ed Hackenbruch]

Cody, i was in a different forum, (not buses) and found this. www.cruiserlift.com   thought this might be of interest to you.

[Ed Hackenbruch]

I must have missed that Cody,....or else i forgot it!   Heck, i don't even remember what is at the top of this page.    First thing i do in the morning is look in the mirror and then at my drivers license and if the pictures matches my face i can look to see what my name is.

[luvrbus]

Folks do what they want on their coaches makes no difference to me one way or the other this post is all about weight distribution Cody refers to engine weight the 6v92 weighs in at 2020 lbs dry that is setting in a 38 inch area,the 8v92 weighs 2414 lbs in a 44 inch area the series 60- 12.7 weighs 2630 lbs spread over 57 inches. He and his welder can support the bays but when it gets down to it means nothing on a Eagle if you have not seen one of these ladies naked it is hard to understand how a Eagle distributes the weight.

good luck Cody on what ever you choose to do

[luvrbus]

Go for it I won't offer you any more info  



good luck

[bevans6]

Cody, it seems to me that your bus is completely unlike any other Eagle, so you and your friends are the ones who can decide if it can support extra weight.  The point about drawing the leverage points out and seeing what the weight will do to axle loading is well taken, if you hang an extra 1,000 lbs ten or twelve feet behind the rear axles, you'll transfer weight off the front and onto the rear axle, the calculation is easy if you draw it out.  As far as a bike carrier/rack is concerned there are a lot of factory made ones around to copy, you can do hydraulic or winch lift.  I'd personally do it so the carrier went down to ground level and the bike rolled on then got lifted, the ramp type are pretty much a pain even for a little scooter.

Without seeing your bus I don't think anyone can have a clue as to if it was done right or wrong, or if what you put in is better or worse than what you took out.  All I can do is say have at it, fill your boots, and make yourself happy!  That's what I strive to do every day, some day's I make it, some days I go to bed early...

Brian

[usbusin]

Cody, I wasn't aware that you put a completely different frame under your Eagle (two 6" I beams).  Maybe others weren't aware either?  Any pictures of what you did would be helpful and interesting.  A picture is worth a thousand words someone said.

[Chaz]

Wow, interesting thread!! I too have a few hash marks as a welder but, I'll leave it at that.

But, the cruise lift link was some really good info for me!!! Even tho I make my living as being creative, I had not thought about the way the "Swivel 78" works, on that site. A very cool idea!! And if the swivel will slide forward it creates it's own ramp. That, to me would be the way to go. It could also add extra room for hauling other stuff on the sides. Very neat item!!

Fortunately, I don't need one for my Harley. I keep a bay open just for it. All I have to do is drop my bars and I have 1/2" to spare. But a Garbage Barge (big bagger type bike) would never come close. (mine is a '46 Knucklehead)

Thanx for the thread and info guys!
  Chaz

[wal1809]

Here are my 2 cents worth.  I have an eagle and a big problem with getting all my toys to where I am going and back.  One solution I cam up with was exactly what your speaking of.  If you look at the frame in front of where your 6v is mouted you will see a hole in the frame that is 1 inch.  That frame is solid steel.  Utilizing the holesI want to be able to mount a carrier for the rear but leave the original reciever hitch in place.  I was thinking of using c channel with a 1 inch hole drilled to match the frame holes and bolting the channel onto the frame.  The c channel would then of course be extended to the rear where it would hole the expanded metal platform for a 4 wheeler (GRizzly 650)  A slide in and out ramp is all I would need to load that beast.  An extension in the reciever hitch would then be added witht he pin to hook the boat trailer to.  That way the weight of both the 4 wheeler and the boat trailer tounge would not be working together when you hit a bump in the road.  It would also allow you to take the 4 wheeler platform off and on as needed

[rv_safetyman]

wal1809, I am concerned about your design.  As you point out, the engine rails are pretty strong.  However, they are supported by the tubing structure in the compartment and that is the area I have been expressing concern about in terms of corrosion and fatigue degradation.

Next, you are moving the load out another foot or so from my calculations (four wheeler is wider than a motorcycle).  Next, I would think the weight of a four wheeler and the support structure would be more than a large bike and that adds to the problem.  Lastly, you are then going to add the tongue weight of the boat trailer at a point at least 3 feet from the rear bumper.  Even with a small boat trailer, that would be a lot of bending moment on the frame.

I think a much better approach would be to have a platform designed that would be added to your boat trailer.  It could be permanent or removable.  You would then have the four wheeler on the boat trailer and part of the weight supported by the trailer axle.  If you used an equalizer hitch system, it would remove some of the downward bending moment on the hitch. 

A word of caution (are you guys tired of hearing me say  that  ) on equalizer hitches.  They put what I will call a "positive" bending moment on the frame structure (think wheel barrow handles and a lifting effort on the back of the bus).  That type of loading must be considered in the hitch design.  For the most part, any good hitch design would be OK with an equalizer hitch, but it is possible to fabricate a hitch and only consider the down force loading.

Another possibility would be to fabricate a small trailer for the four wheeler with a hitch on it for the boat.  The double trailer might not be legal in some states and you would have to a address the storage issue in a campground.

Jim   

[wal1809]

Hello rvsafetyman !!  I still think it will work.  We did discuss the possibility of extending the tounge on the trailer and putting the platform for the 4 wheeler there.  The only problem is I usually have 2 boats at all times.  It was not a problem witht the Ford Excursion as I welded in a hitch reciever on the rear of the 16 foot flatbed.  I tow two 4 wheelers on the flatbed and the boat behind it.  This whole problem stems from needed a launch vehicle.  That is what the 4 wheeler is used for.

I really have not figured out how to cure this problem so I have decided to leave it be for now. 

[Chaz]

By "equalizer hitch" do you mean something like the "crazy wheel"? Seems to me that something like that would certainly help. (??)