Touring - Toba Racks, neat and innovative

I'm usually the last one to know what's new out there but for those that haven't seen this innovative line of racks from Toba, there are a dozen styles that might just fill a niche for tourers. Several with built in additional heel clearance.


http://www.tobapeople.com/en/product/robin/

271249

I wouldn't buy a rack that cantilevers it off the mount 1-2 inches,horrible design.That's a great way to tear the brazeon off of your frame though....

Several models rated for 40kg, that's a bunch. Booger, not sure if you couldn't run your axle thru that extention, like Axiom's and OMM racks.

Not sure of all their distributors in the states but Modern Bike seems to carry their line.

http://www.modernbike.com/b_Toba/

Feature T-Bar (patent-pending): two adjustable arms moving independently from the rack structure to keep the rack parallel to the ground regardless the frame type or size

I infer those front struts are movable . vertically, so will go on whatever seat stay fittings you wish.. Boog.

I wouldn't buy a rack that cantilevers it off the mount 1-2 inches,horrible design.That's a great way to tear the brazeon off of your frame though....

Has anyone ever actually torn off a brazeon like this? I've heard lots of people talk about the risk, but never really heard of it happening. The tensile strength of a good braze is orders of magnitude above most peoples touring load, and far higher than the sheer strength of the M5 bolt holding the rack in place.

Those racks do look pretty nifty, and I do like the ethically sourced milk crate.

Brazeons do break off, but I think it's because they are overloaded. I am not really sure there is an issue here. I would think that the cantilever is going to rotate the rack around the fastening bolt.

Those racks come with a variety if optional mounting hardware that let the specially designed struts mount to either rack mounting points on the seat stays, or directly to the V-brake posts. Not sure what the concern is about the bottom offset being a risk to brazeons though. The lower rack mounting points on every decent new frame I've seen in the last couple years have been integrated (drilled and tapped) into the rear dropouts. And since the maximum rated load of 40 pounds is spread across 4 attachment points, I wouldn't expact any one point to have to deal with more than a 25 pound load - and if thats a load issue for your own brazeon - I'd say there was a design issue - and not with the rack.

The same company that designs and distributes those racks also distributes BionX here in Quebec, Canada, and a long list of other products.

I'm with fuzz on this, before you break off a braze on, unless it was defective to begin with, that bolt is going to shear. I don't think that in itself would prevent me from trying one.

I wouldn't buy a rack that cantilevers it off the mount 1-2 inches,horrible design.That's a great way to tear the brazeon off of your frame though....

The total weight and location of the center of gravity of the loaded rack is the critical factor for whether or not a brazeon would be broken off. The cantilevered rack design would not put more stress on the brazeon than would otherwise occur if the rack was not cantilevered.

But, that design would place a lot of stress on the cantilever itself and for that reason I would be hesitant to buy it unless I could inspect it first in the store and evaluate how robust it appears to be. Just looking at the photos, I would not trust it. I think the rack may be a metal fatigue failure waiting to happen.

I never bother to look at weight ratings, the better rack companies always appear to be more conservative in their ratings while the cheaper racks may be rated by the marketing departments.

Thorn used to rate their heaviest duty rack with a higher rating if you used 6mm bolts instead of the more common 5mm bolts. In other words, the bolts were the limiting factor. Unfortunately I do not recall the numbers that they claimed.

And, weight ratings do not take into account the potholes or other road hazards.

Their 'Roger' model is interesting a bit of a mudguard with a couple small pannier mounts, on the sides ..
'Roger the messenger' adds a slot to hang a U lock on one side

Thorn used to rate their heaviest duty rack with a higher rating if you used 6mm bolts instead of the more common 5mm bolts. In other words, the bolts were the limiting factor. Unfortunately I do not recall the numbers that they claimed.

And, weight ratings do not take into account the potholes or other road hazards.

The M5 bolts (grade 2, not stainless) are rated to something like 2000 pounds of sheer stress. It's been a while since I looked it up, but I'm sure it's orders of magnitude above touring loads.

I never bother to look at weight ratings, the better rack companies always appear to be more conservative in their ratings while the cheaper racks may be rated by the marketing departments.

And, weight ratings do not take into account the potholes or other road hazards.

What you're posting is completely in contradiction with information I get from manufacturers at the trade shows. Would you please site your sources?

PS: Based on your criteria - those OMM racks I'm using must e a disaster waiting to happen. Just don't hold your breath - they've been on the market for years and have an established reputation for reliability.

Hard to say what I think of these. There are some interesting features. I would want to know weights though and I did not see them listed.

The M5 bolts (grade 2, not stainless) are rated to something like 2000 pounds of sheer stress. It's been a while since I looked it up, but I'm sure it's orders of magnitude above touring loads.

Static shear strength is quite different from the force a bolt has to hold when you hit a solid bump in the road. If an M5 bolt would safely handle the weight you propose, that suggests that I could safely replace the five large diameter studs on each of my SUV wheels with a single M5 bolt.

What you're posting is completely in contradiction with information I get from manufacturers at the trade shows. Would you please site your sources?

... ...

Don't have a source for the weight ratings, but I have seen some cheap racks in the store with bad welds that were rated as high as some of the best racks. Have also seen some of those cheap racks in the disposal bin after they failed.

I'm with Booger. The cantilevers create a moment (leverage) that would tend to twist the braze-ons if the rack was swaying side to side. This would put the welds or brazing under alternating cycles of shear stress that could cause failure.
A rack that attached straight down also has considerable leverage, but this can only matter if the rack isn't very stiff laterally. So in general the shear forces would be taken by the bolts, and the braze-ons would mostly be taking compression, which they can stand pretty well.

Tubus has been selling cantilever extensions for their racks for years. They are a very reputable company. If extensions created an issue why would they sell them?

Why would the Toba extensions be any different?

Tubus has been selling cantilever extensions for their racks for years. They are a very repeatable company. If extensions created an issue why would they sell them?

Why would the Toba extensions be any different?

Axiom has also been using these for several years now as well:

271424

Don't have a source for the weight ratings, but I have seen some cheap racks in the store with bad welds that were rated as high as some of the best racks. Have also seen some of those cheap racks in the disposal bin after they failed.

So what exactly is in your opinion 'a cheap rack with a high load rating' ?
Please - be specific as to brand and model. And explain how that might be applicable to this post - where we're discussing a $50 to $60 rack(depending on options). I've personally seen a lot of racks fail - good ones as well as cheap ones. So far its always been from grossly exceeding the load ratings. Most were warranted in spite of that.

And I'll be down to the trade show in Toronto this weekend so I'll ask some specifics regarding various racks and get back to you.

Tubus has been selling cantilever extensions for their racks for years. They are a very reputable company. If extensions created an issue why would they sell them?

Why would the Toba extensions be any different?


In Canada Tubus is distributed by:
Ortlieb USA
1521-15th ST NW Ste.2
98001 Auburn, WA
customerservice@ortliebusa.com
ortliebusa.com (http://www.ortliebusa.com/)

Yeah - I agree - they're a pretty reputable company.

I stumbled upon the Toba racks about a year ago, and I liked the adjustability of the the seatstay arms, but that component seemed overly complicated and I had concerns about their reliability. Now I see that they've expanded the line a bit, and the Ron rack has a more robust looking "T-Twist" attachment (which is available as a separate accessory,) that seems like a step in the right direction. Thanks to robow for starting this thread!

I'm loving the front rack & milk crate, will definitely be getting one of those :)

It obviously isn't an optimal configuration compared to less levered designs, but one assumes everyone knows that. They would just make certain things possible for compromise situations, and most people doing that will probably get by fine.

I wouldn't get too hung up on the sanctity of numbers, the literature often misstates stuff. I would imagine that few companies have done serious tests, are there any industry tests for rack weighting, and if there were they would be difficult to translate into reality.

I was amazed a few years ago when my wife stood on her rear rack (nothing special brand) to attach something high while we were camping and not only did the bolts not snap off, she only managed to slightly bend the rack a smidge and the brazeons didnt complain either.... She is wont to doing things like this, I just shake my head sometimes.

That your wife`s rack didn`t fail really doesn`t surprise me much, djb. But I`m really impressed by her sense of balance, and what kind of kickstand gets the honors? :D

Do these type of racks use the skewer and the brazeon to keep the the mount from rotating? I thought they just mounted to one or the other.Most of them don't look like they go anywhere near where a mounting hole is.

I have a Axiom Odessey rack of similar design and have been using it for years.

It works on any bike, disc or rim brakes.

It would be great for a road bike with short chainstays because the "ears" move the panniers away from the heels.

I have mounted it through the skewer and the dropouts. I prefer the dropouts because it's much less problematic changing a flat.

No worries about it breaking.

Rodar, no kickstand and the bike was leaning against a tree, someone must have held the bike, don't recall.

I wouldn't buy a rack that cantilevers it off the mount 1-2 inches,horrible design.That's a great way to tear the brazeon off of your frame though....

OK So I talked to some of the reps at Toba and Blackburn and Axiom and none of them could tell me conclusively how the loading capacities of the racks are determined. They all stated they are provided by the manufacturers.

However, your argument about 'cantilevering the rack off the mount' has some other engineers I talked to a little perplexed. The bottom interface is either heavy (about 3/16in to 1/4in alloy plate) welded to the rack tubes, or heavy (1/8in to 3/16in steel plate) bolted with TWO no 10 bolts and nuts to the rack struts. The assy is extremely rigid and any load is transferred to the brazeons VERTICALLY. Any inefficiency in load transfer due to an offset would stress the rack plates - not the brazeons. The upper rack stays ( if properly installed), are intended to share the load as well as keep the rack from rotating.

Another interesting item that was mentioned was that brazed joints exhibit their maximum strength when the brazing filler material is stressed in shear, rather than in a direction parallel to the contact surface. So I would think a twisting stress should be the last thing to worry about.

It was brought up, that the failure of a properly engineered and executed brazement, when stressed beyond its load capacity, should occur in the base metal, not in the joint. So if you've had issues in the past - better to consider it a poor quality frame issue rather than a rack design issue.

Burton,
thanks for "just the facts" ;)