Weight limits for heavy duty rear racks?

[RPS]

Has anyone tried or seen a dog kennel mounted over the rear wheel of a heavy duty bike?

I’m curious how viable it would be to mount a medium-size kennel on a heavy duty rear rack.
It would also have to serve for cargo carrying – about 50 pounds should do. More would be better.
Any idea what a reasonable weight limit is?

Murphy’s Law being what it is, what could go wrong with combining the kennel and basket functions in attached pictures on a trial basis? :rolleyes:


P.S. -- Pictures for example only, not mine.

[Ken Robb]

I'm guessing that the limiting factor may be the strength/design of frame rather than the capacity of the rack. A real touring frame with eyelets for a rack is probably fine but a race bike might flex under such a load. Some folks worry about a big loaded saddle bag swinging about. I wonder what will happen when a medium size dog shifts around in his kennel?

I think this rig would be fine on my Riv Allrounder. I doubt that it would have been on my Legend.

[sivat]

Tubus rates their full sized rear racks (cargo, logo, and cosmo) at 40kg (about 90lbs), but if your dog is more than about 20lbs, a trailer is a better option. Just think about what would happen when your dog sees a cat and throws himself against that side of the crate.

[Louis]

Why not a kiddie-type trailer?

That would give you the most flexibility for carrying a large canine or cargo.

[RPS]

I'm guessing that the limiting factor may be the strength/design of frame rather than the capacity of the rack.
Ken, I’d like to first try it on a “solid steel” old Schwinn MTB beater bike I ride around the neighborhoods.
It’s made of mild steel but is very heavy, stiff, and rugged.
The rear dropouts are made from steel plate and have dual threaded holes for attachments – seem larger than normal rack bolts.
I’d expect most of the added weight should rest directly down on the rear axle/wheel so the frame shouldn’t see that much more stress.
The rear wheel is another matter.
I wouldn’t think the load would be as hard on the frame as if a bike had an Xtracycle extension added, or something similar as an example.

In no way am I worried about damaging the old bike – it has no value other than as a beater.
On the other hand finding out if I can make greater use of a bicycle to occasionally replace a car does.

[RPS]

Why not a kiddie-type trailer? Louis, I’ve been looking for months and have found that all options require a lot of compromises. It’s a little complicated because I want to be able to ride on narrow greenbelts and two-wheel trailers seem a little wider than I’d prefer. Also, I’d like to be able to take it with us when we go camping and trailers are bigger and take up more room. If a rack works well, my next step would be to try it on our Cannondale tandem.

If the rack idea doesn’t work out because the load is too hard to handle when he moves around (or holding the bike upright may be too difficult while loading him) then I’m going to buy or build a small trailer.

[palincss]

Simply carrying 50 lb on the back of a bike introduces some serious handling compromises no matter how good the rack is.

Have you considered a one-wheel trailer like the BOB?

[Jawn P]

Big Dummy :)

[Bradford]

It’s a little complicated because I want to be able to ride on narrow greenbelts and two-wheel trailers seem a little wider than I’d prefer.
You should borrow a few trailers and try them out before deciding that they are too wide.

I thought the same thing until I started pulling my son's Chariot a few years ago. I was really surprised how easy it was to pull through tight squeezes, and I pull it almost elusively on greenbelt bike paths.

Also, I have toured extensively in my life and lived without a car for two years, I'd never put weight as high as the rear rack under any circumstances, it is just too dangerous. When I didn't have a car back in grad school, I used to go to the grocery store and laundrymat on my bike. When the weight was high, like in my back pack or on the rack, the bike was unstable way too often, and I went down a few times. When the weight was low, like in panniers, no problems at all.

One more thing. When on my tandem, my wife has a bad habit of letting her mind wander and moving around in strange ways on the back. It is remarkable how badly that can effect the handling, especially at high speeds. You don't want a dog moving around on the rear rack.

Try the trailers. As a pannier snob, I assumed they would be awful. After three years of dragging Little Bradford around (he is now 31 pounds), I am really impressed at how well they handle.

[RPS]

Simply carrying 50 lb on the back of a bike introduces some serious handling compromises no matter how good the rack is.

Have you considered a one-wheel trailer like the BOB?
Yes I have – probably my fallback option.
I just don’t know whether a live load would be easier to control on a single-wheel trailer or over the rear wheel.
I’d hate to buy one and find that it’s useless because it’s too unstable when he moves around.
I’ve also thought about the possibility that he could get into the spokes if not shielded.
The trailer’s lower height should make it easier to load – either cargo or dog. I like that aspect.
Plus a trailer would be easier to use with different bikes (would be nice to pull with tandem).

[RPS]

You should borrow a few trailers and try them out before deciding that they are too wide. Thanks, good info. How wide would you say is your trailer compared to the paths?
Our paths are approximately 6-feet wide with lots of turns.
Kids on bikes sometimes take their share of the middle. :)

[Tobias]

I wouldn’t think the load would be as hard on the frame as if a bike had an Xtracycle extension added, or something similar as an example.
I've seen many pictures of riders hauling kids on Xtracycles, and also in baskets of cargo bikes. I'd guess they probably move around some, but maybe not as much as an animal. The key seems to keep the load as low as possible. Most cargo bikes' load platforms I've seen are very low.