08 June, 2009

Designing a New Saddle Bag Support



We have been selling the Viva Saddle bag support for a few years and, apart from one that broke, most everyone seems very satisfied with them. But I have the urge to make our own saddlebag support. I think we can improve on all the existing designs.

It seems best to have a support that mounts to the seat post rather than the saddle rails or seat stays. This allows the support to slide up and down the post to accommodate various sized saddlebags. The seat post is also strong and is designed for this sort of load.

I also would like to have a quick release version that uses a clamp that opens on a hinge and locks with a cam-type quick release. This is the system used on some of the seat post-mounted racks you see on mountain bikes. Some may be worried about a quick release clamp making the support easier to steal, but it's simple enough to replace the cam-lock with a machine screw.

The remaining question is weight; is the extra weight of a hinge and cam worthwhile? Or would it be better to have it removable by loosening two Allen head bolts? It should be able to support about 15 pounds, which I think is about the max load most would carry. Of course a few folks will want to carry more weight in a saddle bag, but this support would not be for them.

Thoughts? Ideas?

34 comments:

johnson said...

two bolts would be stronger and lighter and cheaper, and take maybe 1 minute to remove. thats where I would go, personally.

Brian said...

Can I suggest a more meaningful design?

How about designing a large saddlebag that doesn't need a support, or has the support built in?

mike said...

assuming the bag itself is still threaded through bag loops, it seems it would be tedious to steal anyway... undo the bag, then undo the quick release...?

2 bolts please. and keep the profile narrow - some of those 'beam racks' are pretty kludgy and completely overdone.

Ian Dickson said...

I'd go with the bolts. I can't see ever wanting a quick release on my saddlebag support.

John said...

I'd go with two allen-head bolts. With the right sort of face only one of the bolts would have to be loosened/removed to take the support off, which is easy enough.

And for my part, I'd appreciate an eyelet for a blinky on the rear.

NatMc said...

A large saddlebag that doesn't need a support has already been designed. it's a cutting-edge product from this new manufacturer called carradice. they call it the nelson longflap.

i made a stand-off using a tube cut from an airborne cold medication package (although five inches of pvc pipe would work too) and it NEVER hits my legs or fender and i never feel it swaying. in fact, it sits farther away from my legs the fuller you pack it. miracle of miracles!

sincerely,

a supporter of no support

Steve said...

I use a bagman support, and the thing that it lacks is a support wire/tube directly over the rear tire. I don't have much clearance between the bag and the top of the rear tire, and my saddlebag sags in the middle right onto the tire, so I can only really use it on a fendered bike otherwise the tire would wear through the bag. It would be great to have some support on the edges AND in the middle.
and two allen bolts is perfect.

Anonymous said...

another vote for bolts.

and +1 on the blinkie attachment


Andrew
(sacramento)

stevep33 said...

Don't most saddlebags have already loop for a rear blinky? But if you would add eyelets anyway, then maybe have a pair of eyelets (like the ones on a Tubus Cargo rack) that hold a proper light.

twblalock said...

It would be cool if you could build in some kind of mechanism to adjust how far back from the seat the bag sits. Saddlebags often hit my thighs when I ride, and so I don't like them. Adjustability could solve that issue.

Anonymous said...

Another vote for 2 bolts vs. cam. Simpler, cheaper, lighter. And don't most of us carry a 4/5/6 anyway?

patates frites said...

What Brian said. Make the bag right and it won't need a support.

Chris Kulczycki said...

Folks need to try an Ostrich bag with a support to see just how solid a saddle bag can be. I also own a Longflap that I never use because I'm spoiled by the Ostrich and don't care for the Longflap swaying and bouncing on a rough road.

The reason I like the idea of a quick release is that I see a large saddle bag as just for occasional overflow from the handlebar bag, not something I'd leave on a bike. But obviously some like to use them all the time.
Perhaps we need two versions?

Tavis said...

I assume that the quick release idea would mean that the saddlebag is attached completely to the support, so that removing the support will also remove the saddlebag? Otherwise, I don't see much use for a quick release. The saddlebag is what needs to be easy to remove, not the support.

To address other comments, the caradice nelson is a great bag, but whether or not it needs a support has a lot to do with frame geometry. I would have to use at least 3 airborne bottle to keep mine from hitting my legs.

For the suggestion about a support directly over the tire, a wrapping of string making a web for the bag to sit on would be easy and cheap.

Ian Dickson said...

stevep33:

The problem that I've had with the blinky loop on my Carradice is that, depending on how full the bag is, the light might point sharply up or down. It's a nice feature, but I wouldn't use it for a primary taillight.

Slightly off-topic:

I've just switched from relying on a large saddlebag to using a handlebar bag with a front rack. I prefer the handlebar bag in every way but one. With a Carradice, I can carry delicate things (like fruit) without any special protection. My handlebar bag, on the other hand, tends to juice the fruit right in its skin. Does anyone have any set-up suggestions that might help?

Thanks.

Le Cagot said...

Ian, why not a long straw sticking out of the handlebar bag? Delicious, nutritious, and cheaper than a Vegomatic. :-)

Justine Valinotti said...

I agree with Johnson: two bolts is the way to go. And John is right, too: an eyelet for a blinky.

If you make the support, I will buy one.

Joel said...

Carradice made (possibly makes but they seem to be out of stock at most outlets) what it calls an SQR bag and mounting system. An attachment device mounts to the saddle post. The bag - a pretty large one at that - snaps on and off.

I bought one without stopping to think that the custom I was riding at the time was designed to have a more traditional close to frame saddle. I could not use it and wound up selling it to someone. The new owner really likes it. He even used it as his only on bike pack for a two week credit card tour in Southern France and Northern Italy

I now have a bike that could use the snap on pack and cannot find one anywhere. So I would certainly be interested to see how this design works out.

Doolio Conteugiaeu said...

That bad in the picture is my style. Well made and functional. It worth every cent as long as it meets my simple requirement.

Typenschild Delete said...

Yeah, what we need( i.e. what I want)is more of a saddlebag decauler.

Rigid or semi-rigid element that is permanently attached to the bag, and a small element that is permanently attached to the post or saddle rails or both. Then some sort of tool-less quick release to join the two.

I don't want to leave any sort of bag attached to my bike while it's locked up downtown.

robatsu said...

I like being able to remove one of these things quickly. Maybe if the mounting bolts were somehow "captured" in the mount much like derailleur mounting bolt. This would make it a lot more convenient to remount and also keep together when off the bike.

Wayne Myer said...

I have been longing for something that uses existing rack braze-ons and canti posts.

Tim D said...

I use a Nelson longflap on my commuter. I am lucky enough never to have had problems with either it hitting my thights or swaying to much. Generally it holds my sandwich box, a change of clothes and sometimes shoes or shopping (beer!). After a large number of years, my old bag wore out and I bought a new one plus the bagman support. Other than providing a stable platform when overstuffing the bag, I don't think the support gives me a great deal. I prefer the bag strapped to the seat post. If the seat straps and post strap are done tightly enough there is little sway. I am lucky enough to live in an area where I don't need to worry about theft too much.

And seeing as I'm only 20 odd miles from the Carradice factory, not only am I buying British, I am buying local as well!

Jay said...

To Wayne's idea... something that uses the canti posts or rear rack braze-ons and ties into the seat post clamp for stability, utilizing the existing QR lever or allen bolt. Happy to sketch it for you.

Chris Kulczycki said...

Many, even most, frames don't have canti-brakes or rack bosses. In fact most rando frames have neither.

Inspector Javert said...

NO QR.

John said...

I've wondered if the Nitto R-10 could be used with rack eyelets. Or assuming it could, whether the strut angle would be too acute to offer meaningful support.

They're priced above my "buy one to satisfy my curiosity" threshhold, so it remains a mystery.

jimmythefly said...

The Nashbar mini front rack can be used on the rear mounted to canti studs or with P-clamps. The new Axiom Phoenix DLX front could probably work the same way, though I haven't used on myself. The axiom one is silver aluminum with a wood mini deck, pretty nice looking, if expensive.

Justine Valinotti said...

I like the idea of a "rear decaleur." It could mount to the seatpost with two allen-head bolts, as others have suggested. But, like the front decaleur, it could not only offer easy bag removal, it could also provide mounting slots for those who ride Brooks Professional and other saddles that don't have bag loops.

brothersterno said...

something I can use to keep my nelson longflap out of the tire. I have a nitto "mark's rack" from rivendell, which works good Ok, but at $90 per rack, I have to pick which bike gets the support and which uses the fender. (oh, hello dented aluminum!)

Something with an adjustable angle, or even two attachment points for height/angle and a little hoop to keep the bag off the tire are all I need. It would be nice if it was light, but that's secondary to works.

I do like the support of a rack, and something which can mimic that without the fuss and expense of installing a rack, and with a tire and seatpost hugging profile to stay stable and out of the way is what I need.

Anonymous said...

Whether or not it's bolted or quick release, I'd love to have something that's easily mounted and transferred between three bikes. More importantly however, it has to LOOK clean and minimal even if there's no bag there at all (thinking of big clunky quick release gizmos...makes me gag).

Andrew said...

For those who think that a big bag negates the need for a support - consider us short bastards. Even a small bag like the Barley rubs the tyre or fender on my bikes.

The Bagman is ridiculously overpriced so I'm sure VO can come up with a better and cheaper solution.

Anonymous said...

I think the post mount is a good idea. Seat rails are for clamping the seat . . . I tend to also prefer bolts for a mount. QR's are just a bit too much hardware clogging up the space in there . . . I've used them for post mounted racks, fenders, and trailerbikes, etc. The convenience to me seems overshadowed by the annoyance of having that chunk of metal between your thighs.

Karl said...

What I'd like to have is something that clamps to the seatpost (not the rails) and has some sort of simple, low-key, quick release, so I can quickly and easily take my bag with me.