2014 Montana 3150RL

[LoLadTraveling]

As stated in the subject box, we have a 2014 Montana 3150RL left-handed trailer. We recently purchased 2 recumbent trikebikes along with an Alpaca bike rack to mount on the back of our trailer. I use 2 ratchet straps attached to the receiver to minimize side sway and for/aft movement. As youse know, there is a lot of "whipping" at the back of a fifth-wheel while driving. What I want to do is install 2 eye bolts to the side of the back window in line with the top. Then attach 2 ratchet straps to take some of the weight off the receiver, thus helping to minimize movement some more. Thanks for any help, Laddie

[Mikendebbie]

Trying to understand what you want to do...below is a random pic I googled for the rear of a Montana. Is my sketch correctly showing what you want to do?
Hopefully others will chime in with ideas - but this sounds like a bad idea to me.
Your eyebolts would have to be anchored thru studs/structure, with big washers on the inside wall and the outer skin. It seems to me that you will be adding moment forces to the back wall that it was not designed to resist...not to mention inviting leaks and cracking the fiberglass cap. My knowledge of structural engineering and moments has just been exhausted! It just sounds like a bad idea to me - unless my sketch is wrong. Seems like you need to figure out a way to resist the rear end sway by bracing back to the frame (keep the bracing horizontal and low down at the frame level)

[jsb5717]

I would certainly avoid the eye bolt idea...that's just begging for other problems. There are simple solutions for tightening the rack in the receiver. Use something like this and call it good. A little movement isn't going to hurt the bikes but screwing eye bolts into your trailer and putting tension on them just might be an expensive mistake.

Something like this:
https://www.amazon.com/Tightener-LIB...xpY2s9dHJ1ZQ==

[LoLadTraveling]

Thanks much. I understand everything you are mentioning. Your sketch shows what I was planning on doing. The only difference is the style of my rack. The top of the rack almost reaches the middle of the rear window. Now I'm wondering what about putting the eye bolts more towards the bottom of the window. Laddie

[Mikendebbie]

Originally Posted by LoLadTraveling

Now I'm wondering what about putting the eye bolts more towards the bottom of the window. Laddie

My comments would be much the same. I just don’t know if the rear wall and cap was design to resist/withstand an imposed tension load of any type.

[LoLadTraveling]

I have a receiver lock already. What I'm trying to accomplish is to minimize the for & aft whipping of the bikes while traveling on our SMOOTH ROADS! Tried calling Keystone, but they're shut down until April 8.

[lightsout]

Almost ALL bike racks have a disclosure not to use on back of trailer (for the reasons discussed above) with that said install a receiver on the front o f the truck and put the bikes or a roof rack if possible (assuming it does not block forward view).

by the way Keystone will not advise you on this as it would be a liability to them...

[Donjamin]

Having opened up the rear cap on my 2016 3160 to install a backup camera and to rotate the 50 amp electrical connection to accept a dog-bone electrical cord connector, there is no wood backing in your fiberglass shell for your eye-bolt to go into next to either the windows either top or bottom. Your dealing with about a 1/4" to 3/8" inch thickness of fiberglass on the rear cap shell. As others have mentioned, You are just asking for trouble if you think you can secure an eye-bolt though the fiberglass. I'd look for an alternative such as the hitch clamp mentioned in a prior post. That's cheaper than having to do a fiberglass patch job on your rear cap. That's my 2 cent opinion.

Don

[Montana Man]

As long as there is no slop in the receiver and bike rack, it will be fine. Those bikes go through more riding them than a ride on the back of a trailer. I've had motorcycles on the back of my trailer and had no problems.

[laverdur]

A word of caution regarding the weight of a bike rack and the bikes. My Monty came with a 1.25" x 1.25" receiver. Most decent bike racks require a 2" x 2" receiver. Yes, I could have used an adapter to get from 1.25" to 2" but that only puts the load further away from the receiver and increases the leverage the load can exert on the receiver when hitting bumps in the road. I unbolted the entire receiver assembly and took it to a metal fab shop to have them rebuild it with a 2" x 2" receiver. When I removed the original assembly I was able to see a tag which said the max load for the original receiver was 150 lbs. Whether that means 150 lbs dead weight or some other value related to force exerted by movement of the loaded bike rack. The weak link in the whole setup is the flimsy pieces of U-channel that are tack welded to the back end of the I beam. The receiver assembly bolts to these U-channel pieces. For that reason, I still observe the 150 lb limit, My load is typically less than 60 lbs so I'm hoping that all the bouncing around will not add more than 90 lbs of force.

[Leftie Canuk]

Originally Posted by Mikendebbie

Trying to understand what you want to do...below is a random pic I googled for the rear of a Montana. Is my sketch correctly showing what you want to do?
Hopefully others will chime in with ideas - but this sounds like a bad idea to me.
Your eyebolts would have to be anchored thru studs/structure, with big washers on the inside wall and the outer skin. It seems to me that you will be adding moment forces to the back wall that it was not designed to resist...not to mention inviting leaks and cracking the fiberglass cap. My knowledge of structural engineering and moments has just been exhausted! It just sounds like a bad idea to me - unless my sketch is wrong. Seems like you need to figure out a way to resist the rear end sway by bracing back to the frame (keep the bracing horizontal and low down at the frame level)

I agree with your "moment" concerns - we watched two kid bikes failing around on a travel trailer's rear rack, and then swerved when the rack broke off and the two bikes got squashed like bugs with the following traffic. Our concern led us to a firm in Montreal that made racks that bolted onto the pin
box, using the original pin box bolts (at least Grade 6 !), with some flame cut mild steel "ears" projecting forward. Across those two ears were mounted some aluminum gutter-type channel in which sat the bikes. The carrier also had a backstop to which the bikes were secured and locked. I was able to stand in the truck box and take the bikes on and off the rack. The DW watched the bikes in the rear view mirror. One big advantage of this set up was the limited moment in the pin box area - basically the G force at the pin was the same as that generated on the bike rack.

We have since seen a few more pin box mounted bike racks, mostly DYI, and they seem to work very well. My recommendation would be to bolt the rack to the pin box, avoiding welding it onto the pin box, unless it is fabricated and welded by a qualified shop.

BTW, I agree that any thoughts of attaching anything to the rear cap is just a large repair waiting to show up. The instantaneous loads on the straps and fasteners could be large, and eventually would no doubt pull off chunks of fiberglass after creating lots of tiny stress cracks in the gel coat.

[CaptnJohn]

I just put bikes in the truck bed by the aux fuel tank. No way would I consider bolting anything into the rear cap/wall! I have a 2" receiver on my Montana~~ says 300#. I have a rack that I put back there when off grid for 2 generators and a compressor. Never worry about the bounce and sway.