Axiom Journey 2429 bicycle rack

[bowlofsalad]

Hello,

I purchased an axiom journey 2429 (I paid a bit over $45 with shipping) a while back with the intent of placing my first ever ebike battery (48v20ah) and various other riding essentials on it. The total weight of what I placed on the rack was likely around 30lbs, probably a little less. I spent some time looking, reading, and researching bike racks as I often do, I was looking for something that had an excessively high weight limit. This rack had a limit of 110lbs, with the weight of my load of around 30lbs, I thought the rack would more than handle what I had to place upon it. After 500 miles, most of which were ridden at or below 20mph (using things like a cycleanalyst and a 3 speed switch made certain of this), the rack broke, describing where it broke might be a bit difficult, but it broke right where the bottom post ended inside of the tube. By bottom post, I mean the post that attached to the bottom holes rather than the upper holes. You'd have to have the rack and remove the bottom posts to understand their length and how far into the tubes go, but basically the breaks in the tube were right beneath where the three tubes are welded together.



I was surprised and also disappointed that the rack broke, but honestly, when reflecting on idea that the rack broke after 500 miles with only 30lbs of it's 110lb rating is pretty atrocious. Sadly, after a few days of going back and forth, they denied their lifetime warranty on the rack as well. It's not the end of the world that the rack broke, in fact I am glad it did. All I can say for certain is, if you want a job done right, you'll probably have to do it yourself. I ended up making a rack myself and it turned out great, it weighs a whole lot more than the journey 2429, but my application isn't the weight weenie with just a spare tube on the rack. Perhaps they made the rack for occasional light duty and the 110lbs is purely marketing. All I know for sure is, when installing the rack, I had only one nut on for about 10 seconds, I had to let go of the rack for a few of those seconds and in those seconds, I watched the rack slowly wobble back and forth under it's own weight. That should have been a pretty clear indication as to how strong the rack was, it did last 500 miles, but that is pretty paltry and basically a waste of time making the purchase at all and installing it.

My advice is to make a rack yourself or have someone make it for you, out of steel. The rack you make yourself is something you can fix, and feel confident and happy about. The worst case scenario, you end up making something that is a piece of junk and need to make it again better, it sure beats paying 40-50+ dollars for another rack. In the time they'd answer your e-mail you could make a new rack.

Things that will hold a lot of excessive weight probably shouldn't be made out of aluminum. Aluminum has no fatigue limit, it will shatter like glass. Steel has a fatigue limit, it will bend or tear like cardboard. Steel and aluminum has basically the same strength to weight ratio. You may assume that aluminum is stronger, it simply is not, but it is more expensive.



A little more detail about the rack and my experiences with it.

The rack broke on one of the bottom vertical leg, I was about 15 miles away from home. Not only did the leg break, but it had popped apart so the rack was completely freely sitting on only one leg and two arms. I was a little stumped on what to do, there was no way I was riding home with that. I had pulled over and was holding the thing so it wasn't bending wildly begining to accept my fate that I needed to call someone for help somehow. At the moment I decided to try and do something about being basically stranded,to my tremendous luck, I looked down and found a nice blue coat hanger on the ground. I wrapped the hell out of the broken leg on that with this wire coat hanger and made sure the thing was good and tight. I set my three speed switch to low and took the least bumpy roads I could. Amazingly, I made it home without further incident with just the wire coat hanger keeping that leg together.

I didn't want to be out of an ebike while a secured a more permanent solution (DIY bike rack or get a replacement) so I wanted to try and repair the rack. My first try and was lots of jb weld (basically a strong glue). I cleaned the area with sand paper and acetone as best I could and gooped the stuff all over and inside the broken leg. I let the glue set for around 24 hours and then went for a short ride. It wasn't long that I could see cracks beginning to form After 5 miles, which was around my total trip, I could see a deeper crack, the glue didn't seem like it had totally failed yet, but it was sure to sooner or later. My next try was to take a coupe of long pieces of old 1/2" stock tubing I had, and using some spare round tubing clamps, create a sort of gusset to bridge the gap of the break and use some spare round electrical clamps suggested by a member of this forum (ykick) for use on torque arms. http://endless-sphere.com/forums/viewtopic.php?f=2&t=49474

I went for another ride, this gusset attempt seemed like a pretty decent solution. During this second ride, I could hear a sound that I am certain was cracking aluminum, I stopped and took a look at the rack on the cracked leg, dreading the thought that there was a crack in some place that was going to make the rack totally trash. For whatever reason, I decided to take a look at the other side and saw a crack almost parallel to the other break. I headed home, and decided to just gusset up the other side in the same way I did the other side. I think I ended up riding another 50 miles at most with both legs completely broken but being held up by gussets, after that I decided I was done riding like that, it wasn't worth the risk and so on. That was when I retired that rack, got the materials to fabricate a new rack, and went on riding.

 

[amberwolf]

Just as a note: In my experience most of the "weight ratings" for racks like this seem to be an absolute maximum *vertical only* limit, and does not account for the forces applied to the rack when hitting bumps or potholes or the side-to-side sway they will experience (even minutely) from pedalling actions or the change in loading during leaning in turns, or when a bike is leaning while on it's kickstand.

Long before I got into ebikes I used all my bikes for cargo carrying, often heavy things, and I found pretty quickly that most racks can't actually hold more than a quarter or less of the weight they list, because of the above things that either change the angles at which stresses pass thru the structure, or multiply the forces on the rack tremendously for an instant here and there, probably well beyond the ability of it to support that "weight".


Side-forces can be helped if the rack has cross-triangulation, but most of them don't have any at all, and you can't add it to most of them because it'd have to pass thru the wheel itself to do it. For racks that stick out far enough from the back end, you can triangulate with an X across back end of it so the X's crosspoint is high enough above the tire so it doesn't rub the lower bars of the X, and have an angle to those lower bars different from the top X bars so they can reach the mounting points of the rack at the frame, or use them as secondary mounting points if possible.


With no cross-triangulation, you have ot either have extremely stiff rack structure and low loading of it, or the materials must be able to flex (like chromoly steel bike frames do) without cracking internally under the loads. Aluminum frames of racks can't usually flex without cracking, most often at the points where the rack mounts to the bike or where the pivots are for the mounting legs at the rack frame.


Racks that don't have any pivots at the rack frame are stiffer and will have a lot less side flex than those that are made of multiple pieces, but they also don't fit as many bikes with a single rack size/design, so they're not as popular or as cheap to make, and are less common (or at least, used to be).


The way the rack mounts to the seatpost or seatstays matters, too, cuz if that doesnt' have any triangulation it will also allow sideway and the same problems happen.


Easy to make a rack stiff in a purely vertical direction, but the heavier the load on it the less that matters structurally.

Stiffening it sideways or making it flexible in a way that doesn't allow breakage is a lot harder, apparently.


Custom-made racks that are a single piece (welded/bent/etc) are probably going to be lots stronger than most "universal" racks, regardless of what material each is made of--so I expect your new self-made rack will last you longer, depending on how it's designed.

 

[dogman dan]

This is an axiom journey rack.

I am a bit confused at the moment. You put this rack on a hard tail bike, or a bike with suspension?

 

[bowlofsalad]

Suspension.

 

[HAROX]

Chalo's quote from "Bike Seat" thread, about a year ago. Maybe the concept hasn't lost its integrity. A frames and Arches are key attributes of this rack here, I guess...

Single vertical rack stays only work in a few limited circumstances, where a relatively rigid rack top is firmly affixed at two or more points so it can't yaw.

In most circumstances, vertical stays should form a V (as viewed from the side). It also helps stability if one of the pairs tapers inwards when viewed from the back. The Tubus Cargo rack is an example of everything done pretty much the right way:

It has that arch Amberwolf was talking about, but it is less the arch and more the A-frame that the stays form that contributes stability to the rack. It's also made of tubular chromoly steel, which is a great material choice. As a result, the rack is rated for 88 pounds-- more than any other bicycle rack I am aware of.

But a rack does not have to be nearly as optimized as the Tubus Cargo to be plenty stable, if it has four solid mounting points to the bike frame. Three solid points aren't nearly as good, and four points where two of them are soft (as when mounting a rack on a racing bike or suspension bike, with p-clips) are worse yet. In those situations, the rack must provide its own rigidity the way the Tubus Cargo does.

I see you are gleaning information from more recent (same subject) threads from REAL members, not trollers, however I see the point of the cargo rack design, the way chalo depicted.

 

[dogman dan]

That type of rack, installed on a bike with rear suspension, will break it every time. It's trying to turn the rack into a spring, bending it and breaking it.

 

[bowlofsalad]

That type of rack, installed on a bike with rear suspension, will break it every time. It's trying to turn the rack into a spring, bending it and breaking it.

I am not sure I understand.

 

[dogman dan]

Maybe I misunderstand myself. Most all racks except seatpost type racks are not designed for use with a rear suspension bike. When you attach one end of the rack to the frame near the seat, and the other end of the rack to axle area that is moving up and down, it bends the rack eventually breaking it.

But on your bike, maybe it was possible to attach both ends to the moving swing arm?

 

[bowlofsalad]

Maybe I misunderstand myself. Most all racks except seatpost type racks are not designed for use with a rear suspension bike. When you attach one end of the rack to the frame near the seat, and the other end of the rack to axle area that is moving up and down, it bends the rack eventually breaking it.

But on your bike, maybe it was possible to attach both ends to the moving swing arm?

Precisely, very good. Both mounting holes are on the swing arm.

I am honestly surprised anyone would design anything other than having rack mounting holes only on the swing arm. I was guessing you meant that the idea of a suspension bike would cause racks to break, clearly I was wrong.

 

[dogman dan]

Ahh, I misunderstood then for sure. Beg to report sir, I'm an idiot.

You posted great pictures, but I never saw exactly how you had it mounted on the bike in a wide shot.

With that type of rack, which I thought is designed for a hard tail bike, It might not be possible to mount it entirely on the swing arm of all FS bikes.

I've seen other rack threads in the past, where racks had been designed with a pivot, to allow mounting on a FS bike without bending any parts of the rack.

And I've seen broken rack threads where ordinary racks were put of FS bikes, with the moving swing arm connected to the non moving frame.