As with my
review of the Thorn Mercury, I am assembling this review of the Trunk Bag because information was scarcer than I'd have liked while I was shopping and I reached a position where I could supply some for others. My
key unanswered questions were:
A. Given that Ortlieb specifies that the rack rails this bag mounts to must be parallel, will it nevertheless fit a rack with rails not parallel such as my Tubus Vega and other Tubus rear racks?
B. Is a fitted bag secure, stable, and easily removed?
C. Is the bag helpful as a hold-all for bits and pieces on day rides, or is it ridiculously oversized for that (and perhaps intended mainly for use as a grocery container)?
Before I get to the answers, it might be helpful to explain why I wanted such a bag in the first place. Sometimes I rely too much on logic, and forget that the premises of an argument are as relevant as its validity, for the real-world value of its conclusion. I reasoned that I would be leaving my Vega in place between tours and hence would have it on day rides. Given that I would be carrying that platform, surely anything I wanted to take with me would be located most securely on that very platform. In other words, why hang a bag precariously from the handlebars or the saddle when it could go on a rack.
The premise I had overlooked adressed the matter of stability. It turns out there is available a reasoned response to the rhetorical question immediately above. And that would point out that it is easier to stabilise a big bag that hangs from two hooks than to stabilise a big bag that sits on a narrow platform.
And that's likely another reason why rack bags designs are few.
Nonetheless I didn't need a big bag. Or did I? Certainly I didn't want a tiny bag either. In winter I might want it to hold a pullover and a rain jacket, and some food and a lock and some tools. I also had it in mind that I might head off cycling with a good friend from time to time with the intention of picnicking lavishly somewhere pleasant, and that a decent sized rack bag might replace the small backpack that had carried our provisions on past such occasions.
With this sort of consideration in mind I took a punt on the Trunk Bag, having ascertained in a bricks and mortar bicycle store that it might fit a Vega rack. (Yes, I purchsed the bag from that store.)
Key answers:A. Yes. The Ortlieb Trunk Bag mounts well to a Tubus Vega. It would mount even better to a rack with parallel rails, but the ingenious mounting mechanism can handle some misalignment.
Here is the mechanism:
The active bits are the four feet with their spring-loaded cams. The two cams on each side rotate together when you draw down the relevant handle. Here is a closer look at one of the cams:
Effective operation of the cams relies on accurate adjustment of the feet, which can be slid laterally to accommodate wider or narrower racks. The cams seem principally to operate against one another across the rack; however they also catch the tube and wedge it against the base. The main issue raised by non parallel rails is the possibility of the mount sliding towards the narrower end of the rack and hence losing the cross-tension. In practice a cross member on the Vega limits movement if you set up the bag to mount adjacent to it.
B. Again, and emphatically, YES. I filled the bag to the brim with four kilos worth of essentials on my recent tour of South Gippsland, where it was tested by an incident that I
described here. In short, the bike with tyres overinflated for the conditions bounced so violently and persistently on a corrugated gravel road that both front panniers were dislodged partially from their racks.
In contrast, the heavily loaded Trunk Bag showed no effect whatsoever.
And yet, the bag is easier to mount and remove than are Ortlieb's easy-off panniers. To fit the Trunk Bag, you simply align the mount with the rack on one side while tilting the bag, hold down the lever on the oher side, un-tilt the bag so that it rests on the rack, and release the lever. Done. Nothing else required, except perhaps to reassure yourself by attempting to remove it without deploying one of the levers. When you want to remove it, that's even simpler: pull down a lever, tilt the rack, and it's off.
Some careful setting up is required to achieve this security: you need to space the mounts the optimum distance apart, using an allen key to unlock the adjustment. There is a bit of trial and error involved but it's not difficult. Ortlieb recommends the allen bolts be checked frequently but I haven't bothered.
C. Again Yes. At 800g it is the same weight as a Carradice Nelson saddlebag but at 12 litres holds three litres less. A better analogue for volume might be the
Carradice Pendle, which is 170g lighter and holds a litre less. The Arkel Tailrider referenced and linked in my opening post is specified at the same volume and weight as the Pendle. The Trunk Bag is arguably more streamlined than the Pendle, and simpler to mount than the Tailrider. It could carry enough for the aforementioned picnic, and has no trouble swallowing a pullover and jacket. Here it is with just a (grey) synthetic pullover and a few other bits:
And yet whether or not I have a lot in it in it, it doesn't much get in the way.
Nevertheless, the Trunk Bag has its
shortcomings.
Perhaps the most salient is its hard plastic internal lower surface, which means that when you don't have much in there the hard contents will rattle. I've been known to carry soft wraps just to prevent this. I imagine the Carradice and Arkel alternatives are much quieter.
Second, on a single rail rack like the Vega, you can't use it in combination with Ortlieb panniers. That's because the clever mount dominates the rail. Traditional saddlebags don't display this incompatibility. (You can use it with panniers on a dual-rail rack such as the
Tubus Logo.)
Edit: No, it won't fit with Ortlieb Back Rollers even on the Logo.And third, the Trunk Bag is neither compressible nor expandable, notwithstanding its roll-top closure. Ortlieb roll-top panniers can be rolled more or less, and how much you roll them makes a significant difference to the volume of the bag. The same is nominally true of the Trunk Bag, but whereas the panniers can be secured at any available volume the Trunk Bag's closing system is much more limited - as you may be able to see from this dodgy photo the closing flap has a very narrow range of engagement with the velcro strips that secure it:
And hence if you attempt to overstuff the bag you soon find that the velcro simply won't engage. The 12 litre capacity - nominally about the same as an Ortlieb Sport Roller pannier - therefore represents a hard limit, and you can't squeeze in that extra stubby of beer even for a short run from the pub to your campsite.
So, given its shortcomings,
am I satisfied with the Trunk Bag?Kind of. The left side of my brain still points out proudly that it uses the rack, and that it demounts in seconds, and that it must catch a little less wind than a similar sized saddlebag. However, the right side observes that a saddlebag in a similar size would have been lighter and quieter and more adaptable, and that its not using the rack would be a problem with no real world consequences.
Finally, John, to answer your
questions:
> On tour, nothing went into the Trunk Bag that could not have gone into the panniers. However, the Trunk Bag is more easily dismounted than the panniers, and I had thought I might use it as a rear-mount handlebar bag, placing in it things that I might want to take into a cafe with me. In hindsight, not the smartest idea.
> The bike seemed to handle very well with 4kg in the Trunk Bag, but it may well have handled even better with the same weight carried lower in panniers.
So there - everything you always wanted to know about the Ortlieb Trunk Bag RC but were afraid to ask. I cannot imagine that any of you has an interest in learning yet more, but if I am wrong and you have a question then fire away.