Out of control sway

[cazual6]

Originally Posted by OTRA15

Moreover the trailer in question is nineteen feet long with one axle, and could be towed safely without much if any WD or SC.

The sway problem here is very simple to fix IMO.

I thought you were done with me? You do love me!!!

[cazual6]

Originally Posted by Rocinante

Clearly, people who have those hitches love them. Must admit, when I have an excellent hammer, everything starts to look like a nail. So, I understand it.

Meanwhile, we did not want to deal with the extra weight of said fancy hitches, and have been very happy with the one our dealer sold us (Equal-i-zer). There are plenty of good anti-sway hitch brands / models out there.

To focus on the OP's problem, it seems pretty clear the sway was caused by putting excessive weight far behind the axle of their FC19. He's working his way back to eliminating this problem:

• He's agreed that loading genny's in the front won't solve it.
• He's agreed that he shouldn't be putting 4 bikes back there.
• He'd like to try his rack with 2 kids' bikes while the rest are inside. (better than 4!)
• He knows to investigate how much the kid bikes wobble when they are mounted on that rack.
• He's considering other bike rack solutions, though he's reluctant to put bikes up on the roof (doesn't matter why, but it seems this will not work for him).
• He's evaluating / improving his current anti-sway hitch setup.

So, overall it seems he's made quite a bit of progress. Color me hopeful.

I appreciate you pointing that out. I am stubborn, but I can clearly see, I am well out-knowledged here. At the most, two kids bike in the back, the minute I feel a sway, bikes will go inside the AS. The bike mount will serve as my flag pole for the most part and a hanger for while on site.

FYI: Rook rack won't work, I can't get the wife to carry the bikes that high

(I don't know why the pictures won't orient right in this forums)

[SteveSueMac]

Originally Posted by cazual6

I appreciate you pointing that out. I am stubborn, but I can clearly see, I am well out-knowledged here. At the most, two kids bike in the back, the minute I feel a sway, bikes will go inside the AS. The bike mount will serve as my flag pole for the most part and a hanger for while on site.



FYI: Rook rack won't work, I can't get the wife to carry the bikes that high

Hi again. A few final thoughts from me - and please accept this with all the love that's behind it.

You acknowledge being stubborn AND well "out-knowledged". But you're STILL talking about going ahead with a plan that those you understand to have more knowledge than you on the subject have repeatedly told you not to do. That's just plain irresponsible.

I can only conclude you are more stubborn than appreciative of others' knowledge and experience.

If you FEEL the sway, you're already at a significant disadvantage! There is plenty of advice in the forums about emergency maneuvers should you need them, but will you pay any more attention to that advice than you have so far here? If history is any indicator of future behavior, I confess I don't have high hopes that when (not if) you feel the sway you'll be able to safely react and adjust.

Last, regarding your wife's preference for not putting the bikes on a roof rack, is she aware of the discussion in this thread? You've now had hundreds of reasons why you absolutely should not be using a rear hitch on your Airstream, especially for bouncing bikes. What reason do you have, other than your wife's preference, to not pursue a safer solution?

I literally can add nothing more to this.

[Rocinante]

Yeah, I'm kinda done here as well. Nice flagpole, though! Good luck to you.

[cazual6]

Ok. One bike. On my trip back from Big Bear, I only had the smallest bike in the back. That was with no gens, no sway bar, just what I had when the problem started. I can say, with certainty, this was ok. Regardless your concerns, this is something I have already done and did so. I drove slow on the way down. Posted a pic when I made it down safely. Started at 45mph, 50, 55, 60 and maxed at 65mph with no sway at all. I had uneven roads, trucks passing me by, all the ingredients you all have mentioned that I should have been concerned about. I played it safe and stayed at 57mph all the way home. The theories presented here and concerns are all VALID. But I did field test. I did the one bike, and being overly concerned is safe is a good practice. I can tell you one bike is OK.

I don't want you to think I am careless. I didn't take a chance on the way back. I listened to all the advice and didn't risk anything.

I appreciate all the brutal advise and concerns. I really do. No offense was taken. As they say, if you can't take, then don't ask for it. I certainly asked for it.

Thank you again for all the good insights.

[SailorSam205]

Originally Posted by cazual6

I will definitely read up on it. Thank you.

Update ( a few minutes later): Holy crap!! Talking about scientific explanation!!! Makes me need to read up on my formulas again. This is way over the top!!

Yup, enough science to give most people a migraine, I went thru it over several days and a few asprin!

Just a FWIW, and this may start a flame war over hitches, one comment that stuck out during my slog thru was that ALL hitches that allow the trailer to cause a pivot on the ball are susceptible to sway. My understanding of the comment is that only if you can eliminate that possibility are you completely safe. Again my understanding, the only hitches in the US/Can that meet this requirement are the Hensley design units. Most anti-sway hitches are some form of friction control and the Blue Ox is a spring that work to diminish sway forces that occur at the pivot point (tow ball). Hensley hitches use physics to virtually move the pivot point up near the TV rear axle. It would be interesting to see a paper like this one documenting the forces when using a Hensley style hitch.

[slowmover]

There's no reason not to use a better hitch. Best hitch. The only ones who knock them haven't a clue of what's best.

Start from scratch, OP. Lose the present bike rack and find a better solution.

If this tail chasing thread causes you to reconsider tires, or brakes, or electronic antisway devices, better brake controllers, etc, it's all to the good.

[AVDESIGN]

I'm not sure I have ever seen a topic get people more emotional than "carrying bikes on the back of an Airstream..."

I admire you CAZUAL6 for hanging in there for so long with the "Naysayers", the "Can't-be-Done'ers" and even the "You're an idiot for even trying'ers"...

Please posters, don't take me wrong; other opinions, constructive criticism and multiple perspectives are very important in solving any problem. However, "It can't be done!" is often the easy way out of a problem. Stick with it Cazual6! Listen to all points of view, keep your original goal in mind and then FIND A WAY!

I wonder what kind of comments would have been posted to the Wright Bro's had there been an "AirForum" like this in their day? Maybe... "The law of gravity won't allow that thing to leave the ground...", "You're going to kill someone if you don't listen to reason...", "Listen to the majority of the people telling you it won't work..." and so on.

In one post I remember reading someone saying "since the bikes are located 10 "feet" behind the axel they are 10 times heavier...". At first, this made some sense to me since I am a pilot and have to consider weight and balance and location of weight. But in this case I started thinking; good thing they didn't measure the distance in "inches", the bikes would have been 120 times heavier. The law of physics MUST not be ignored, but they also must be understood, examined and applied correctly. Remember Newton's 3rd law; "for every action there is an equal and opposing action", this can be very helpful (i.e. Weight Distributing Hitches--they don't reduce the actual tongue weight but they do utilize other forces to transfer the point of those forces to negate rear-end drag and other problems). Through the use of physics and engineering you will find solutions to your problem. Keep it up!

I was dealing with the same problem (or goal), that is, to safely carry bikes on the back of my Airstream...
I read posts, talked to engineers, regurgitated physics lessons from college and eventually came up with a viable solution to carry bikes on my 30' Classic. I addressed all the issues and found a solution that works VERY well for me--
My goal:
-bikes on the back,
-compensate for decreased tongue weight and change in center of gravity,
-access to trunk and pull-out drawer,
-weight of bikes distributed safely between frame and monocoque shell
-and last but not least aesthetically pleasing to the eye.

I was told, "don't waste your time, go with the Airstream approved Fiamma". For me, the Fiamma bike rack wasn't a good solution. It still puts all the weight on the frame (upper supports don't carry any weight, only there for stability) and it inhibited access to the rear trunk. (See pics) After hours/days/weeks of analysis, I came up with a solution that works for me.

Cazual6, I don't offer my solution to say this is how you should do it, only to say that there is a solution for you if you keep at it. My point again is this--Where there's a will there is a way, don't give up!

I'm sure some will inquire how I did it... I will be providing a lengthy explanation soon with pics but in the meantime I offer these pictures:











And why I didn't go with the Fiamma...

Not strong enough....


Oops!...



Limited access to rear trunk and weight directly on bumper/frame....




Thanks AirstreamForums for being such a great source of information and entertainment!
Happy Airstreaming to all!!!

[HowieE]

Those that may have read some of my posts will probably agree my approach is closer to the Wright brothers than the Nay Sayers when it comes to bikes on the back of an Airstream I was carrying bikes on the back of my trailer several years before Airstream. who had long said it could not be done, finally offered a carrier.

While weight on the rear has a calculable effect on the overall system the problem here was is a poorly installed and misused WD system.

[OTRA15]

AVDESIGN,

Hopefully you appreciate that there are orders of magnitude between:

-- your well thought out bike rack, on the back of a 29' or 30' trailer, with multiple points of support/bracing; and

-- a rack for 4 bikes hanging way off the rear of a 19' single-axle trailer, from a single point without any further bracing/support.

Issues of "sway control" for the two set ups are quite dissimilar IMO, to say the least.

Moreover, no matter how well designed a bike rack is, it may still violate the Airstream warranty on a new trailer -- another matter, but worth considering.

Also, it seems a bit disingenuous to label some here as Naysayers to the general concept of a bike rack, when most were simply trying to keep cazual6's specific mobile weapons system off the road as a hazard.

[dkottum]

Note that the bikes on the broken Fiamma rack above are electric bikes, exceeding the 70 lb weight limit specified for the rack.

Note that although the upper brackets carry no weight, the hold the rack from downward rotation toward the rear, and large oscillations on uneven roadways, which is their purpose. That means less dynamic force working on the frame and bike rack, as well as a more stable Airstream.

[AVDESIGN]

OTRA15 -- I totally see the huge differences between my 30' classic and the OPer's trailer... and in no way am I saying that since my solution works for me the same solution will work for him too. He needs to address MANY issues (in my opinion) before he arrives at a workable solution... Such as: distribute weight of rack correctly between body and frame, stabilize bike rack to multiple points, possibly reposition weight inside trailer to the front to compensate for added weight on rear, etc, etc, etc. All of our rigs are an added danger to the roads but doesn't mean we should all just stay home.

I remember one trip in our Airstream... I got on the freeway, accelerated to 65, touched the brakes when someone cut in front of me and the trailer began to sway like crazy! What was different from this trip vs. all the other stable trips I had made before?? Pulling over and examining the inside of the trailer I found that my wife and daughter had moved everything to the back bedroom (cases of water, our personal duffle bags of clothes, lounge chairs and folding camp table). They thought it would be nice to have the kitchen and living area free of any cargo for when we stopped for breaks. These relatively light items moved to the rear had a huge effect on the overall stability of the trailer.

My point (without any offense intended towards anyone) is: Don't stop trying to find a workable solution to a goal (carrying bikes on the rear without sway) just because some say it can't be done.

HowieE -- I agree, WD and stability of bikes and rack are the main issue here. I applaud you for being an innovator.

dkottum -- Regarding electric bikes exceeding weight limit, TRUE! But the Fiamma bike rack (like the OP's bike rack) places all the weight on the frame which according to many contributes to frame-body separation. Weight needs to be distributed between frame and body... IMO. Also, Fiamma solution greatly obstructs access to rear compartments in my case. However, I know the Fiamma rack has made many AS owners very happy.

I actually see his stubbornness to find a solution within his working parameters admirable. He brought his problem to this forum to be analyzed and scrutinized by many different minds. He is trying different options (some by trial and error) eventually with persistence he can arrive at a workable solution to his goal--again, in my (not so humble) opinion.

[Tom_T]

PSS on Yakima Swing Daddy etc. bike racks -

Bottom line - you can't use the Yakima Swing Daddy on the back of your trailers ....

... but it will work great on the back of the self-powered RVs & Class B Van Campers/RVs, your regular Cars/Vans/SUVs/CUVs etc. for better rear hatch/door or trunk access & clearance, on your TVs when not hitched (or maybe with one of those over-under double receivers when hitched - but then you may have more than ideal distance hitch to TV-rear-wheels that Andy T. talks about).

Note that the Swing Daddy is not an inexpensive rack, nor are the AS & Fiamma racks either!

Cheers!
Tom
///////

[Papou]

Originally Posted by OTRA15

Yes, you are right. It would also be helpful IMO to know, however, what the actual tongue weight is before WD hook-up, just to make sure that the trailer is loaded within AS specs.

In the case of the OP here, knowing the tongue weight before and after loading would seem to be a very important data point to have.

Thanks,

Peter

The PDF file refers to my rig that I have since 2011. You are right about the absence of tongue weight information. I do not have this info. At the moment that I take measurements, I do not unhitch my travel trailer on the balance. But for your information, I do not fill fresh water in my TT when I leaving home; this is the case on these measurements. Also note: the two 30 lbs. propane tanks was full when I was on balance with my rig.
This set up was perform by CanAm (Andy Thomson) from London, Ontario, Canada and I am totally satisfied of it! Great job...
Michel

[cazual6]

Thank you all for caring and continue to give me insights.

AVDESIGN, I appreciate your encouragement. I was fortunate enough when I was a young lad that I had great mentors to teach me the ways of the world in my industry (Audio/Video) and in life. Imagine when I was 20 running a crew of 6 to 10 guys who were at least 10 to 15+ older than me in another state and sometimes in another country. Talk about learning LIFE quick! That is how I am able to take brutal honesty, sort through the say'ers and do'ers with a smile on my face.

There is/are ALWAYS a solution. Trial and Error is one way to find out. However, in my case, this was too dangerous to do trial and error without any insights.

Through this forum, I have received many many insights. I can tell by the responses if they are do'ers or just say'ers. I'm not saying neight is wrong or right. Any insight to help my problem is welcome.

For me, I am a do'er.

AVDESIGN, you must be of age to know what a "sparky" is.

One of the things I will "try" to do is find someone to cut my bike mount so it can go closer to the frame and redrill the holes for the locking pin. My next trip is not until Sept 2016, so I have a little time to do some research.

For those of you worried about me being a weapon, I will be leaving last weekend of Sept, around 11a. I am should be on the 101N heading to Morro Bay.

My sway bar already arrived.

I even looked at one of the suggestion which was to put the hitch in front of the TV, I saw some great pictures. The wife was opposed it since it would block my view. Also, the way the Traverse front is, I don't think it would look good in the process.

For the moment, my solution is:
1. One bike in the back (I am very temped to try two, but one I know will work)
2. I'm gonna try to get the mount shank shortened.

I will continue to read up and listen to anyone who has the insight to care enough to help me through this problem.

[RareStream]

I see you took my advice about getting the bikes closer to the trailer.

Now, you MUST secure the top of the rack and bikes to the midline of the trailer so they absolutely cannot move whatsoever. You MUST do this. This is the cantilever action that will not only lead to sway but ALSO rear end separation.

Do NOT ignore this step!!! That little anti-rattle crap is NOT strong enough at the top of the bikes to stop all movement!!!

[Tom_T]

For Caz & Others Showing the Bike Rack Alts. -

Good info. & good rack options above for Caz & all to see,

But a word of warning on some other bike rack option(s):

For my `60 Avion I don't need access to a rear storage hatch, although I was initially hoping to utilize one 2" receiver mounted bike rack for both our `88 VW Vanagon Westfalia (& our cars) - which has a huge up-swinging rear hatch - with the Yakima "Swing Daddy" bike rack, which allows you to swing the entire rack on a pivot arm over to the curb side & grass strip or sidewalk to load/unload, & to fully access the rear hatch unobstructed (there is also now one other swing-out rack out there since I got ours, but I don't recall the maker).

I thought this Swing Daddy would be great for us on the back of the Avion too - just for the loading/unloading at curbside.

However, I found out that Yakima & other mfgrs. making various types of Auto/Truck/SUV/RV rear receiver mounted bike racks - including our Swing Daddy - specifically tell you NOT to use them on the back of trailers due to the amplified movement & bouncing back there.

So you really have to pick bike racks which are specifically designed for trailer use, & to take the amplified forces & bouncing on the back of any trailer. I think the ones pictured above were designed for such service.

As is the Stromberg sold at CW, eTrailer, etc. - although it sticks out too far as in Caz's pix on the prior page (his is Stromberg or similar I think, which I also have - but untried as yet). They can be drilled for a 2nd retaining pin hole further rearward on the tube, in order to bring it closer into the rear of the trailer body (the bikes handlebars'/pedals' width allowing), & may also need to have it's tube cut shorter for clearance to the trailer body &/or frame at that new innermost position. But don't cut the tube unless necessary, so you can still use it in the further out position for clearance/etc. with the full tube lenght for bearing within the tube.

Bottom line is - you can't use the Yakima Swing Daddy on the back of your trailers. But it will work great on the back of the self-powered RVs & Class B Van Campers/RVs, your regular Cars/Vans/SUVs/CUVs etc. for better rear hatch/door or trunk access & clearance, on your TVs when not hitched (or maybe with one of those over-under double receivers when hitched - but then you may have more than ideal distance hitch to TV-rear-wheels that Andy T. talks about).

Note that the Swing Daddy is not an inexpensive rack (mine was $170 IIRC), nor are the AS & Fiamma racks either!

Cheers!
Tom
///////

[Tom_T]

Originally Posted by RareStream

Now, you MUST secure the top of the rack and bikes to the midline of the trailer so they absolutely cannot move whatsoever. You MUST do this. This is the cantilever action that will not only lead to sway but ALSO rear end separation.

I would recommend caution in attachments to the AS/other trailer body halfway or whatever up, since the frame for the body is much lighter weight, than is the main steel tube or "C" section frame below the floor & extending to the bumper.

While you can stabilize somewhat at the body mid-line, you really should have securing tie-backs down to the bumper &/or main frame extensions holding the bumper. I've seen typical webbed-belt cargo tie-down straps around or hooked to the main frame itself, & up to the top of the bike rack & bikes, successfully used for this purpose.

Be Safe,
Tom
///////

[HowieE]

This has worked for over 15 years. The secret is the clips on the window sill. The bumper can carry the vertical load but not the rotational load. That load is carried by the straps to the window sill.

[RareStream]

Originally Posted by Tom_T

I would recommend caution in attachments to the AS/other trailer body halfway or whatever up, since the frame for the body is much lighter weight, than is the main steel tube or "C" section frame below the floor & extending to the bumper.

While you can stabilize somewhat at the body mid-line, you really should have securing tie-backs down to the bumper &/or main frame extensions holding the bumper. I've seen typical webbed-belt cargo tie-down straps around or hooked to the main frame itself, & up to the top of the bike rack & bikes, successfully used for this purpose.

Be Safe,
Tom
///////

While your advice is sound, it doesn't necessarily apply the same way to an Airstream as it does to other trailers.

The point of securing the bikes to the structural ribs at the mid-line is to take some of the load OFF of the frame, to prevent oscillations and dynamic movement which over time will rip the shell FROM the frame.

Securing EVERYTHING to the frame alone is going to contribute to the problem.

That's why the Fiamma rack is designed the way it is; the two upper anchors (that sadly break in half) are secured to two vertical support ribs on the back of the trailer to keep the dynamic forces from being SOLELY tied to the frame itself.

Howie in the post above this one has the RIGHT idea.