Too much on the back?

[LtDan]

Would like to have some other opinions on this, took a short trip today and couldn’t tell much in the way of the trailer being out of balance, hooking and unhooking the tongue weight felt normal.
Both bikes and rack is 100 lbs, mini split compressor and bumper mods are an additional 85 lbs., though not as far back. With no bikes I at 180 lbs can jump up and down on bike rack and see some frame flex between original bumper and the rear most bolt up through the body.
I do plan on modifying bike rack to bring it forward maybe 4” which would help if I keep this setup, that and maybe reinforce the frame rail where I saw the flexing.
I’m still not wild about how far back the bikes are but if you stand back and look at it it seems balanced with the front of the trailer as far as weight and length from center?

[Ron in BC]

I was thinking that you could move the bikes a little more than 4" forward if you removed the one pedal and also moved the half tubes that hold the wheels.

Where's your spare tire, under the tongue? It does a bit to balance the double rear load that you have.

If your spare tire is in the back of the truck then it might be a good idea to weigh the tongue, it's hard to tell the weight situation just by looking.

Ron

[Upfisk]

At the '19 Osoyoos rally we had our tongue weighed. We had 2 bike's on the back and they might have weighed 110# with the rack. Our tongue weight was right at 400#. Since then we have been adding weight to the front. We now carry 5 gallons of water under the passenger side dinette, another 2.5 gallons under the driver's side dinette. We look forward to weighing the tongue again this year. Weigh your tongue it is amazing information.

[LtDan]

The spare is up under the optional storage box that has about another 80 lbs, so it would seem to balance out.
Just concerned about the stress on the frame where I mentioned the flexing.

[Rossue]

Met someone recently with a new 21NE who had the rear bumper strengthened significantly with another bar of steel just inside the bumper itself running parallel. Also had the receiver modified. This was to be safe with 4 bikes on a 1UP. Wish I had taken a picture.

[dosby]

Out 17B with 4 bikes at the end (~150lbs total) and one lithium battery barely balances out our front box and gaucho bunk bed - tongue weight is still 400 lbs, a little more than 10%. Greater tongue weight is a better issue to have, though, than vice versa.
Without the bikes, I had to keep heavy items at the back of the trailer: grill, food, etc.

[Ron in BC]

Originally Posted by Rossue

Met someone recently with a new 21NE who had the rear bumper strengthened significantly with another bar of steel just inside the bumper itself running parallel. Also had the receiver modified. This was to be safe with 4 bikes on a 1UP. Wish I had taken a picture.

I took a look at the actual measurements involved and I have to say that seems like a very good idea.

The frame is only 4" to about the rear of the rear tires and then it necks down to 3". The distance from the rear bumper to the nearest bolt is 20"

So put in a significant load way out from the bumper, add in another 20" and that adds up to a nasty amount of stress on that rear bolt. Stress and flex aren't a great combination.

It would be possible to add reinforcement to the side of the 3" part of the frame, ideally along to the next bolt. A little bit of stuff in the way but nothing that can't be undone and re-attached.

Ron

[Ron in BC]

Actually, since I carry a large storage box at the rear of my trailer, I decided to take a closer look at the situation. I don't like what I see.

The through bolt is 5/16" and it has a 5/8" flat washer. The bottom of the rectangular tube is relatively thin sheet metal. The load at a distance is significant. Every time the trailer hits a bump and levitates the rear load and it bounces down the force on the small diameter washers wants to make the underside of the frame concave. The more that happens the more likely it will start flexing at the point where the vertical bolt passes through the frame. Not a great situation.

I put a wrench on the nut and, while it wasn't really loose, it wasn't really all that tight either. So, two minutes later, and it's now tight without starting to collapse the frame tube spreading the load on the rectangular tube.

Ron

[GregWCIL]

Originally Posted by LtDan

Both bikes and rack is 100 lbs, mini split compressor and bumper mods are an additional 85 lbs., though not as far back. With no bikes I at 180 lbs can jump up and down on bike rack and see some frame flex between original bumper and the rear most bolt up through the body.
I do plan on modifying bike rack to bring it forward maybe 4” which would help if I keep this setup, that and maybe reinforce the frame rail where I saw the flexing

If you can see flexing on metal that is not good. Your 100 lb. Is almost twice as far behind the bumper compared to the stock setup. So possibly equal to double the stress. Plus add 50 lbs for the condenser compared to the spare..
I just passed a trailer yesterday with a bike rack. I was amazed how much it was bouncing. Multiply that stress by thousands of cycles and something is going to fatigue.
What do the rear-most frame bolts go through?
Any chance you could put the bikes (or at least one of them) in your tow vehicle? Just saw some folding bikes at Camping World.

[GregWCIL]

Originally Posted by Ron in BC

Actually, since I carry a large storage box at the rear of my trailer, I decided to take a closer look at the situation. I don't like what I see.

The through bolt is 5/16" and it has a 5/8" flat washer. The bottom of the rectangular tube is relatively thin sheet metal. The load at a distance is significant. Every time the trailer hits a bump and levitates the rear load and it bounces down the force on the small diameter washers wants to make the underside of the frame concave. The more that happens the more likely it will start flexing at the point where the vertical bolt passes through the frame. Not a great situation.

I put a wrench on the nut and, while it wasn't really loose, it wasn't really all that tight either. So, two minutes later, and it's now tight without starting to collapse the frame tube spreading the load on the rectangular tube.

Ron

None of us know what Escapes’ engineering theory was. Are they simply using those bolts to hold the fiberglass shell on the frame? Are they trying to help the frame by making it more of a “unibody” and leveraging the rigidity of the fiberglass body?
If the latter, bolting through a hollow steel tube (especially a thin-wall tube) is poor engineering. A better approach would be something like angle iron welded to the tube sides for bolting. I’m not suggesting this since welding on a frame can also cause stresses.

[Ron in BC]

I guess the engineering theory is that a bolt vertically through the center of the frame is the quickest way to hold the body on the frame. They did that on the early 19s and that didn't work out too well which is why the recall involved welding a bracket to the frame and bolting to it.

Once you start adding weight at the rear, and more importantly, weight at a distance, it ends up being supported by the rear most bolt. Since, right from the get go it's 20" ahead of the bumper the further rearward you go the more lever arm you have. At some point you're going to get to the point where flexing starts and that's not good.

I don't think that this is a situation about trailer balance but the amount of weight and how far aft it is from the last frame bolt.

Bike racks scare me, especially those holding several bikes. I was minutes behind a horrible accident on I-5 where a bike rack had come loose and with the following vehicle swerving to miss it another rolled at high speed. It wasn't pretty. I tend to keep my distance from large bike racks and switch lanes if I can.

Ron

[Rossue]

That's why I coil a cable lock around the 1UP rack to the bumper. Both for some theft protection and to keep it attached to the trailer like chains to the tow vehicle.