Author Topic: Ortlieb Trunk Bag review  (Read 4598 times)

Moronic

  • Full Member
  • ***
  • Posts: 167
Ortlieb Trunk Bag review
« on: January 02, 2022, 03:32:27 PM »
Carradice makes a bunch of bags in various sizes that hang from a bicycle saddle. The company makes two bags that sit on top of a rear rack. Not many other companies make rack bags at all. Topeak used to make one that slid into a channel on a bespoke Topeak rack, and there was a period when I dreamed of one day fitting both to my bike. I never got there, in part because I had a rack already.

In the Topeak example we probably have the reason why rack bags are scarce: the platforms offered by rear racks differ, and a commercially successful bag would need to fit most of them. The challenge of designing an effective harness that can be constructed for a dollar at a factory in China has outmatched most who have thought about it and could initiate production.

The Canadian company Arkel rates an honourable mention here for its Tailrider, which I rejected partly because I adjudged it too small and partly because it was not clear that it would attach securely to the rack I have now, a Tubus Vega. My other complaint about the Arkel is that it weighs only 149g less than the 800g Ortlieb Trunk Bag that I was to settle on, which looked to have much more capacity. Spoiler: likely it doesn't.

So I purchased a Trunk Bag RC, the suffix indicating a roll-type closure. Here is Ortlieb's web page for the bag: https://www.ortlieb.com/en_us/trunk-bag-rc+F8422#

And here is the bag half full and mounted on my bike:



More to come/



« Last Edit: January 07, 2022, 08:06:28 AM by Moronic »

John Saxby

  • Hero Member
  • *****
  • Posts: 1866
Re: Ortlieb Trunk Bag review
« Reply #1 on: January 03, 2022, 09:32:30 PM »
Interesting set of questions & observations, Moronic - thanks.

I've never been quite sure what problem a trunk bag was s'posed to solve.  I did have  one made by Voyageur,  which had pockets on three sides, a foil-lined main compartment (to carry a lunch?), and a zippered/expandable top pocket with laces and a drawstring atop that. Velcro strips at the four corners held in place.  Tare weight was very modest, around 300 gms as I recall.

Quite a useful-looking item, but I only ever used it once on a tour.  it was way more than I needed for a day ride, and with the bike in touring mode, it got in the way of the seat bag that holds my tools.

Issue remains, how to use the top of the rear rack?  The solution I've found for past several years is to stash my tent on top of it -- see photo below. On a rare couple of tours where we stayed in hard accommodation, the rear rack carried only the Arkel Dry-lites you see, and a mesh bag with rain gear sat on top.

Some people can stash their tent into a pannier, but the length of my tent's pole segments (18") make it better suited to the rear rack. My tent is quite light, between 37 & 47 oz depending on the trim.

A couple of questions, then -- sorry if I missed this info from your tour report:

    > What did you stuff into the Trunk Bag that couldn't go elsewhere, e.g. into panniers?
    > And, did you find the weight of bag + contents, mounted higher up on the bike, affected its handling at all?

Cheers,  John


Andre Jute

  • Hero Member
  • *****
  • Posts: 3862
Re: Ortlieb Trunk Bag review
« Reply #2 on: January 04, 2022, 05:15:53 AM »
A useful subject. There's a rack top bag in the future of a quite a few cyclists who're thinking of converting their bikes to electrical assistance. Over a certain size, battery assemblies just won't fit the front triangle (desirable for better distribution of the weight), and must be fitted on the rack top. You could use the rail the battery mounts to, which also guides the electrical connection, but a bag covering the battery makes the whole bike less of a thief-magnet.

Moronic

  • Full Member
  • ***
  • Posts: 167
Re: Ortlieb Trunk Bag review
« Reply #3 on: January 04, 2022, 08:36:58 AM »
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.  ;D







« Last Edit: May 02, 2022, 12:17:07 AM by Moronic »

JohnR

  • Sr. Member
  • ****
  • Posts: 497
Re: Ortlieb Trunk Bag review
« Reply #4 on: January 04, 2022, 03:50:08 PM »
A rack bag will hold a similar amount to a medium-sized pannier so, if the required baggage on a trip can be put in a rack bag then I think that's preferable to the lop-sided loading of one pannier. In addition, with a rack bag on the centreline of the bike there should be less aerodynamic drag. I've never felt that the height of the bag above ground level is an issue. It's a lot lighter than the rider, most of whom is even higher off the ground.

I've got both the Carradice Super-C and Carradura rack bags which have each clocked up significant miles. Both are held in place by straps which can accommodate a range of rack widths and are moderately easy to fit or remove. The Super-C uses more robust and rain-resistant material and, for me (31" leg length), the main drawback was squeezing the front end of the bag under the rear of the saddle. That won't be an issue for someone with longer legs. I used it on my supported LEJOG where there was usually room to spare expect for my rain jacket which, on days when it might be needed, was strapped on top with some bungee cords. It was easy to take the bag off the bike in the evenings to carry to my room. The Carradura bag is slightly wedge-shaped so fits better under the saddle and there are two options for the height. However, the maximum capacity of the main compartment is less than the Super-C bag but the Carradura bag has two mini flop-down panniers.

After doing the LEJOG I decided it was time to try some weight reduction and dispensed with the rack and rack bag and fitted the Carradice Lightweight Audax bag supported by the Carradice Bagman. This configuration appeared to have less aerodynamic drag than the rack as the bike appeared to go slightly faster and I used that baggage option on a group ride last October. Both saddlebags and rack bags have the problem of trying to find something small which has migrated to the bottom. I'm currently using a Carradice Maxi saddlepack with the intention of adding more capacity when needed using (i) a top tube bag, (ii) this small frame bag https://www.wiggle.co.uk/evoc-multiframe-pack-medium?sku=103071669 (which fits neatly at the front end of the triangle), (iii) a bag which hangs under the handlebars and (iv) a caddy in one of the bottle cages. I've yet to see how this pans out in reality but having several bags facilitates segregation of what's being carried. (This last paragraph is drifting off the main topic but can also apply if needing a bit more capacity than is offered by a rack bag).

PS: This http://thorncyclesforum.co.uk/index.php?topic=12905.0 is also relevant.
« Last Edit: January 04, 2022, 03:52:48 PM by JohnR »

PH

  • Hero Member
  • *****
  • Posts: 1813
Re: Ortlieb Trunk Bag review
« Reply #5 on: January 04, 2022, 06:07:23 PM »
Nice review Moronic, well thought through, i only stopped by to look at the photos and ended up reading it all, even though I have no interest in the product. It's a shame the bag monopolises the rack, the result IMO is too much product for the capacity.
I have two sizes of Carradice saddlebag, shared between three bikes with bagman supports, also a smaller Ortlieb saddlebag for the other bikes.  I didn't so much choose the Carradice, it's more that that's what touring cycles had and although I've moved on from many of the other standards, the saddlebags have stayed.
One thing your review didn't mention was the ability to attach stuff to the outside, I presume this isn't an option?  I dislike keeping a rain jacket in a bag with anything else (That's not to say I never do it, I just avoid when possible) It doesn't make sense to keep it in a bag, which you then have to open when it's raining, then put a damp jacket back into when it stops!  Mine is usually, strapped on top of a Carradice, or in a stuff sack strapped to the rack when using the Ortlieb.

mickeg

  • Hero Member
  • *****
  • Posts: 2344
Re: Ortlieb Trunk Bag review
« Reply #6 on: January 04, 2022, 09:40:59 PM »
...
I've never been quite sure what problem a trunk bag was s'posed to solve.  ...
...

I mostly use them for riding around near home, but only when I do not plan to lock up the bike somewhere where theft could be an issue.  I do not mind it being bigger than a small saddle bag, I can put a jacket or lunch or both in it. 

One of mine has been used regularly as a gym bag on a rack that I could attach to a seatpost with a clamp.  That one, when I got to the gym I left it attached to the rack and unclipped the rack from the seatpost so I could take the rack and bag inside.

But on tour, I use something bigger, usually a 20 to 30 liter drybag.

I have a large rather odd looking Racktime bag that has a hard shell shape, picked it up at a swap meet from a former Racktime dealer.  Not sure if it was a prototype or what, but it is rather large so I can shove a lot in it.  And it has a quick release attachment to Racktime racks, which I have a couple.


Moronic

  • Full Member
  • ***
  • Posts: 167
Re: Ortlieb Trunk Bag review
« Reply #7 on: January 06, 2022, 09:32:32 AM »
It's a shame the bag monopolises the rack, the result IMO is too much product for the capacity.

That could be about right.

The other side of it might be my misapprehending of the rack I have. It's very narrow, and might be seen more accurately as a pannier hanger, much as the Duo is. With that top available for supporting a cylindrical load between the pannier tops, either as John Saxby demonstrates above or in a transverse arrangement as Ortlieb suggests for its rack bags.

So in saying to myself that my day ride luggage should be on he rack, I am missing the point. After all, if I leave the Tubus Duo bolted to the front fork, I accept that it won't contribute unless I mount panniers to it.


I didn't so much choose the Carradice, it's more that that's what touring cycles had and although I've moved on from many of the other standards, the saddlebags have stayed.

And maybe because they're a good idea that has stood the test of time.

One thing your review didn't mention was the ability to attach stuff to the outside, I presume this isn't an option?  I dislike keeping a rain jacket in a bag with anything else (That's not to say I never do it, I just avoid when possible) It doesn't make sense to keep it in a bag, which you then have to open when it's raining, then put a damp jacket back into when it stops!  Mine is usually, strapped on top of a Carradice, or in a stuff sack strapped to the rack when using the Ortlieb.

Yeah good point, and no there is no option to add anything to the exterior of the Trunk Bag. Again, unlike the front and rear roll-type panniers.

The special thing about he Trunk Bag is its ease of attachment, and then as JohnR observes it is neater than running a single pannier. On balance I'm pretty happy with it, but it doesn't have the versatility that made Ortlieb the market leader.

I'll also add that it comes with a shoulder strap that clips on at each end.
« Last Edit: January 06, 2022, 09:56:42 AM by Moronic »

Danneaux

  • Administrator
  • Hero Member
  • *****
  • Posts: 8072
  • reisen statt rasen
Re: Ortlieb Trunk Bag review
« Reply #8 on: January 06, 2022, 11:16:18 AM »
Quote
...The other side of it might be my misapprehending of the rack I have. It's very narrow, and might be seen more accurately as a pannier hanger, much as the Duo is.
I'm running a Tubus Logo Evo on one of my randonneuur bikes...a use where I also prefer my expanding rack pack/trunk.

I fitted a sheet of Dupont Zytel resin using nylon P-clamps (cable ties would also do) and this gave a solid untapered platform for the rack trunk atop the fairly narrow, tapered rack top. My trunk attaches with velcro straps threaded through the platform at each corner.

It has worked well for me over a number of years now. Though I rarely use the rack trunk with rear panniers, the secondary/lower pannier rail on the Logo Evo nicely carries both at once without mutual interference.

I recently modified a Logo Evo for a friend who wanted a similar setup to mine at lower weight. I used a holesaw to lighten the nylon rack platform and attached it with cable ties. I left the upper portion of the lower tubular rack rail in place and used a cutoff wheel to remove the lower run of that secondary rail. A little paint and nylon hole plugs and it looked factory fresh. He uses fairly narrow, lightweight panniers with his rack trunk, so they remain stable on the remaining rack struts with no heel strike. I recycled part of the lower rail to make a lateral brace fitted with a threaded boss above the rear mudguard blade for direct attachment so the upper 'guard struts were unnecessary. The slight weight reduction over the original rack would not have been worth it to me but was important to him, so....

Tubus' steel racks are easy to modify if you are skilled at brazing and have an oxy-acetylene torch and hobbyist framebuilding supplies as I do. I've removed supplemental struts and added integrated light mounts, bottle/cargo cage bosses and tie-down loops/lash points for bikepacking friends before repainting. Mods void the factory warranty but there have been no problems to date and the hacks added a lot of utility for their users. So long as one uses appropriate gauges of chromoly steel, it is also easy to make very strong racks from scratch to suit nearly any application or bag. The ones I made for my custom full-suspension Folder are strong enough to support my 78kg body weight when I stand on them. I usually go for stock Tubus racks myself because they are a readymade and durable solution at a fairly reasonable price given the materials and construction methods.

Best,

Dan.
« Last Edit: January 06, 2022, 11:32:10 AM by Danneaux »

John Saxby

  • Hero Member
  • *****
  • Posts: 1866
Re: Ortlieb Trunk Bag review
« Reply #9 on: January 06, 2022, 10:32:25 PM »
Thanks, Moronic, for starting this thread, and ditto to all for the informed commentary. "All you ever need to know about Trunk Bags, and then some" -- this thread is a good example of why the Thorn Cycles Forum is a good example.

Take a collective bow, gentlemen (he said, with a self-congratulatory  ;) )

mickeg

  • Hero Member
  • *****
  • Posts: 2344
Re: Ortlieb Trunk Bag review
« Reply #10 on: January 07, 2022, 02:25:18 AM »
I use a Tubus Logo for touring with my Nomad or Sherpa.  Top platform is so narrow that when I get home from a trip, the Logo comes off and a different rack with a wider platform top goes on the bike.  That said, I really like the Tubus Logo as a very solid pannier hanging rack for loaded touring.

Before I bought my Logo, ... (wow, that was 9 years ago, where has the time gone?) ... I used a Surly rear rack for touring.  Now I only use that Surly rack for around home use on my Nomad.  Has a really wide platform for a rack top bag.  I have a vintage Cannondale rack top bag that matches the Surly width.

My Lynskey, I use a Nitto rack around home.  Looks light, but it is steel so quite heavy and is rated for light duty weights.  No separate rails for panniers.  I got the used Nitto rack for pennies on the dollar at a swap meet.  That platform is not as wide as the Surly but is much wider than the other racks I own.  I use a Racktime Addit rack on that bike for touring with panniers.  Racktime platform is 120mm wide, the Nitto platform is 128mm wide, both measured from outer to outer width with my caliper.



Moronic

  • Full Member
  • ***
  • Posts: 167
Re: Ortlieb Trunk Bag review
« Reply #11 on: January 07, 2022, 08:35:13 AM »
Possibly the Trunk Bag would work quite well for certain touring loads on a Logo rack. Two Back Rollers and a Trunk Bag would give me 52 litres, or about the same as two rear panniers and one front. Between the extra weight of the Logo over the Vega and the 800g weight of the Trunk Bag I'd pay one kilo for the extra space, and I'd save the weight of the Duo front racks and two Sport Rollers, about 2.5kg all up. So if you only needed the space of three panniers, you'd be 1.5kg to the good.

Again though it seems a saddlebag would be more versatile. And would work with the lighter Vega rack. Edit: And the speculation above is redundant, as the Trunk Bag is not compatible with Ortlieb Back Rollers, and likely other Ortlieb panniers, even on a Logo.
« Last Edit: May 02, 2022, 12:20:59 AM by Moronic »

mickeg

  • Hero Member
  • *****
  • Posts: 2344
Re: Ortlieb Trunk Bag review
« Reply #12 on: January 07, 2022, 12:42:03 PM »
First two photos are my Sherpa with the Logo rack on my Florida trip in Feb 2017, used Backrollers and a separate drybag that I could strap on top.  The Backrollers were higher than the Logo platform, so the drybag sat between the Backrollers just fine.

I like a drybag for that amount of stuff, as I often have my food in the drybag on top and the volume of that varies greatly during a trip, it is easy to compress the dry bag as I eat more of the food.  At the end of the trip the dry bag was empty and shoved into a pannier.  At that time the only thing on top of the rear rack was a tent pole bag.

If I anticipate needing more volume than a drybag, then I use the Ortlieb Rack Pack that is 31 liters, third photo, and in that photo there is a blue drybag between the Rack Pack and seatpost holding overflow food I could not fit in the Ortlieb.  This photo is on my Nomad, also with the Logo rack.  In this photo there is a small triangular pack in front of the seatpost above the top tube that holds two spare tubes, patch kit and multi-tool.

I have also used some Carradry panniers instead of the Ortliebs, but that is a different topic.

I just find a rack top pack like the Ortlieb or the others that I use to be best for around town riding, not for a tour.

martinf

  • Hero Member
  • *****
  • Posts: 1014
Re: Ortlieb Trunk Bag review
« Reply #13 on: January 07, 2022, 03:24:36 PM »
I think trunk bags work best with racks designed for them.

When I was running old 16 inch Moultons these had wide platform racks front and rear and I used purpose made trunk bags nearly all the time on these bikes, either just the rear or both rear and front depending on volume needed. 

Later on I had a Moulton TSR, and I again bought the specific Moulton rear trunk bag for this model of bike. But the TSR was designed to have a frame-fixed low-loader rack for normal front panniers, so that's what I had on the front when I needed the volume. For a (relatively) lightweight bike I felt the load was very stable, the frame fixed front rack meant that the entire load was suspended and that there was very little effect on handling. But total volume possible was less than on a full-size tourer. The photo is of the TSR with (empty) front and rear luggage

IMO trunk bags work better on small wheel bikes, as the platform rack is set lower. On a full size bike, if a trunk bag is the main luggage and it is filled with heavy stuff it raises the centre of gravity of the bike, which I don't like.

My own first choice for day rides is a saddlebag, which saves the weight of a rack. This puts the luggage even higher, but also closer to the main lump of weight on a bike (the rider). But I often use 1 (or 2) panniers on the rear rack on bikes that do have racks as it is less hassle than swapping a saddlebag from one bike to another.

For touring, my usual choice is the "normal" sized Ortlieb Bikepacker Plus rear panniers with drawcord and strap closure (40 litres, plus the optional rear pockets), with the smaller but similar Sportpacker Plus panniers (30 litres) on the front. If I need more space I can add the Ortleib roll-top Rack Pack (31 litres - the same one as Mickeg ?) bungeed to the top of the rear rack. Whether or not I also have the Rack Pack, the tent usually goes on the top of the rear rack, partly because the poles are a bit long to fit inside a pannier but mainly because it sometimes gets packed wet.

I also have the option of the really big Ortleib Back Roller Pro Plus (70 litres) that I use for shopping and for other local errands when I need to carry a lot, but so far I have resisted using them for touring as I reckon they would encourage me to take too much stuff.

PH

  • Hero Member
  • *****
  • Posts: 1813
Re: Ortlieb Trunk Bag review
« Reply #14 on: January 07, 2022, 04:44:23 PM »
Lots of interesting stuff and it demonstrates how much a compromise it all is, swings and roundabouts.
Although a Carradice style saddlebag doesn't use the top of a rack, it does restrict it, I can't get anything bigger than a set of tent poles under it and that's on a large frame with a good bit of exposed seatpost.  It brings me to the point that luggage is best looked at as a system rather than the components. When you so so, the rack matching the bags is an important consideration.  Though I like Dan's creativity, a different rack might not have needed it.  OTOH we work with what we have, I've ended up with two titanium racks, I didn't plan it and one of them has ironically ended up on my heaviest bike, even if my luggage changes I can't see me swapping racks in this lifetime.
Going off thread, I've been looking at the Ortlieb Fork Pack Plus as a way of adding 11 ltrs capacity to the front of my Surly without using a rack, frustrating to find that despite having 18 mounting points (Yes seriously 9 per leg) none of them are suitable!