Need welders advice on Mountaineer bumper

[nosticks]

Ok, so here's the deal. Subject on here a million times, oh no not another bike rack question. Yep, sure is.

The posts I've read here lead me to believe that the units that have a square steel bumper (Mountaineers) just have them tack welded on and they would not support much weight also considering the moment arm a bike mount would include.

I crawled under my Mountaineer today to see just how the bumper was installed. The supports ( rectangular box tubing's about 14 to 16 inches long which you can see in my signature if you look close)are fully bead welded both sides to the frame and where it joins the bumper, all the way around, not the tack welds claimed on this and other sites. It looks to me to be a very substantial weld, but I am no expert. That is why I am asking for an opinion from a qualified welder, there must be a few on this site. I want to use an adapter that clamps with U-bolts around the square bumper and makes a receiver for the bike mount to hold two bikes.

[racerjoe]

even though it is welded complete,the question is what is the box thickness? the reason being if it is to thin hanging a weight from the clamping point (x) amount of distance out will the leverage bend the box tubing. What needs to be asked from an engineer is how much leverage can that tubing take before failing. That may be the reason they do not recommmend hooking anything to it. there will be a lot of flexing back there

[bobsals]

Greetings, the bumper seems to be welded on sturdy enough for any practical purposes. I am not an engineer but a former pipeline welder many years ago. Seems like the welds are sufficient but the metal tubing that connects the bumper to the main frame is kind of thin. However, don't underestimate the strength of steel. It is stronger than it appears. One of the mods that I stated in my video review last year that is posted on U-Tube, mentions the relocate of my spare tire to the rear bumper. I really don't think there would be a problem with a bike rack. Probably not much heavier than the spare tire and holder. No problems last year nor did I expect any.

[Recumbent]

We also have a 2010 324RLQ and did the same look-see about the welds after reading about the tack-welds, but found good welds attaching the bumper to the frame. I purchased a 2 inch receiver from Camping World for $35 that bolts onto the square bumper in a very similar manner to Bobsal's photo. I trashed the original 4 bolts that secures the receiver to the bumper with the use-once-only threads and nuts in favor of 4 standard qaulity bolts, washers and locking-nuts from Lowes. We carry a Hitchrider rack back there that tilts and that probably weighs 60 to 70 lbs. with two recumbent trikes that weigh about 30 lbs each. This set up seems to be working good. Also, with the 2 inch receiver you have the flexibility to attach a cargo tray where your judgement would be needed to not over load.

[nosticks]

Thanks for the replies. I think I'll try it. I have nothing to loose but $1200 worth of bikes and racks, plus the bumper itself. I'll do what Recumbent did to attach. Then inspect after each trip for any signs of metal or weld failure. BTW the attached photo is of the welds.

[racerjoe]

The weld at the bumper looks solid. the metal would tear before the weld fails. also looking at your picture the rec. tubing going to the trailer looks as if has 4 one to two inch welds holding it on. that also should be sufficient for strength. Always when you weld something the weak point is the metal itself the weld should be the strongest point. That point is where maybe people were saying it was only tacked on. Just my guess

[nosticks]

It's just the picture. The welds are one solid bead top bottom and sides of rectangular tubing at the bumper and solid again down both sides at the frame attachment point.

[ray fischer]

I've had the bumper mount rack #37759 frow C/W on mine for several yrs w/o any problem. I use ratchet straps around the bikes and down to frame. My mountaineer came with the pull out bike rack which I didn't care for, so I bolted it closed and added the above which is more stable and easier to use. Strapping them and the way the tires fit in the tracks elimanates the bounce you get with hitch mount racks.

[kylec2]

Our previous rig was a Mountaineer with the square bumper. The bike rack caused the box of the bumper to tear beside the welds; the welds held, but the bumper material riped. We had a welder weld two 90 degree angle iron pieces between the frame and the bumper which provided more surface area to support the stress and flexing the bike rack placed on the bumper.

The factory design lasted 6 months; the modified angle iron supports lasted four more years until we traded in our rig. I am sure there are other ways to add support, but this worked for us and cost less than $25.

[clutch]

Our Mountaineer bumper was tack welded. The local welding shop cut it loose and moved it in toward the coach several inches and then welded the whole leangth of the mounts. He then welded a 4x6 piece of box steel across the frame and welded a receiver to that. We towed a small trailer with a two quads on it for several years so a bike rack would be no problem.