Pannier hook abrasion...and preventing same

[Danneaux]

Maybe put a line of Sugru along the rack bars ??

A superb suggestion, Pete, and -- as it happens -- one I was playing with earlier this evening! Minds thinking alike!

The problem I ran into with the Sugru is where to put it. I decided I didn't want it permanently attached to the rack tubing for a variety of reasons (mostly aesthetic), so I attacked the problem from the hook end of things, basically making a clone of the Ortlieb sizing adapter yesterday. By tonight, I thought I'd got it right, but...no. That's why I turned my thoughts toward elastomers in my last post. What I did was to take a spare pair of hooks and some Reynolds "Release" aluminum foil and wrap the foil over the rack (reasoning the "Release" -- probably some sort of safflower oil -- would not only protect the rack, but serve as a mold release.  I was just bright enough to try this with the hooks apart from the bags, or I'd have had quite a mess when the spare Sugru oozed out the side of the hooks (thankfully, I was also foresighted enough to fit Sherpa with a drape to prevent Sugru-goo from sliming Sherpa as well).

I used a silicone spray as a mold release in the hooks, and it worked.

The resulting Sugru pad (such as it was) was ~16mm, since it fit inside the unadapted hooks. The inside was not quite 11mm, since it was molded over the rack tubes.

The result had problems in two ways:
1) The plug(s) didn't stay in the hooks; the Sugru was not as rigid as a proper Ortlieb adapter and fell out. I used dental floss to tie it in place till I could look at the underside, and that's when I found...
2) The hook pads are only part of the equation. The other part is the clasper hook on the underside that retains the bag/hook on the rack. It cannot be padded in any case, else it can't be retracted when pulled/deployed when released.

I can't really see any way the Sugru could be "adhesived" (stuck) to the inside of the hook without messing up the clasper hook and the little garage opening it emerges from and retreats to. The Sugru can't exactly be "shaped" after it sets like you would expect of Sculpey ( http://www.sculpey.com/ ) or similar acrylic modeling plastics that can be milled post-hardening (on the other hand, Sugru stays more rubbery? I guess you could say). You have to kind of get Sugru "right" the first go-'round in the shaping process. And, it tend to come out looking (at best) like a dab of modeling clay was put in place and then kinda fingered a bit.

I'm now back to square one, thinking the best solution is a 360° wrap of the rack tube itself...along the lines of what Richie has accomplished. If I go that route (and no criticism of Richie's method or result, just personal preference), I want to make it as inconspicuous as possible and in black to match the rack. I also want to make it so the tubing closes evenly on the underside so it is not snagged by the clasper hook.

Justasec...

Okay, I'm back. I just dashed out to the garage, where I found a small salesman's sample of adhesive-lined, cross-linked heat shrink tape. My sample is blue, but I remember seeing it in black as well. Here's a video showing what I have in mind (being careful not to melt the rack's powder-coat or the SKS fenders or the Schwalbe tires): http://www.youtube.com/watch?v=7gdxvdvusqU

Still thinking...

Keep the ideas coming, guys; they're good'uns! If we put the Hive Mind of our collective thoughts together on this, we'll solve this common problem.

All the best,

Dan. (whose days are either not long enough, or too long; it's after midnight and tomorrow already)

[Danneaux]

In my book, Battle Scars > Heath Robinson solutions.

I agree, Jim; whatever solution there is must be simple and as reliable as a stone. Otherwise, yes, scars are better. 

Best,

Dan.

[Relayer]

LOL great pic Dan!   Yes, I do appreciate you guys like a challenge, good luck on your quest.

[richie thornger]

Haha, no offence taken Dan, all of my customisations seem to be ever evolving and never reach a stage I'm 100% happy with. Therefore I never give a moments thought to what it looks like if it's actually working. One day, one day.

[Danneaux]

Good morning, All! (my time, anyway)

In a few minutes' time, I'm setting off on a couple nights' shakedown tour to the snow-covered lava beds at the summit of Oregon's Cascade mountain range, so I spent some time Saturday pondering the pannier-hook abrasion issue once again.

I finally decided to wrap the racks with a couple more layers of the Trim-Brite windshield trim tape...and hope for the best. The stuff stands up to years of automatic car-wash abrasion, so hopefully it will continue to work well in this application over time.

I've spent a lot of time looking at how Ortlieb hooks actually abrade the rack (see: http://www.thorncycles.co.uk/forums/index.php?topic=54.msg20053;topicseen#msg20053 ) and have concluded the tape -- with my compression straps -- is worth a try.

It appears Ortlieb hooks cause rack abrasion in two ways (both related to movement, of course):

1) By banging into the cross-bar stops of the rack. Solution: Spread hook placement as far as possible to minimize lateral (longitudinal, if you look at it from the saddle) movement along the rack tubes and pad the cross-members with a turn or two of tape. And minimize movement by tying the pannier and its contents to the rack with a single compression strap.

2) By hook rotation. Ortlieb use fairly flexible plastic stiffeners, and when the bag is lofted by a bump or vibration, this vertical movement is translated into hook rotation around the rack tube.  It is a fretting movement (back-and-forth) in a concentrated area. I looked at a friend's aged Tubus rack that had been worn raw, and there are little "fret lines" running crosswise to the rack tubing that support what I saw happening with movement on my test rig. Again, the solution is to protect the rack with something thin (like tape) if you choose to keep the sizing adapters (otherwise, go with something thicker, as Richie has done) and -- once again -- minimize the chance of movement by tying the pannier and its contents tightly to the rack with a single compression strap made of nylon webbing. For ease of use, a quick-release Fastex-type buckle makes it convenient to get into the bags.

Dirty or muddy conditions make hook abrasion worse by tossing gritty materials between the hooks and racks. For those of us who feel compelled to, it probably wouldn't hurt to give the hook-rack interface an occasional quick wipe with a damp cloth before mounting the bags on the rack. But then, I uh have been known to clean parts of my bike on long tours (chain, chainrings, cassette cogs and derailleurs with a quick wipe-down of the frame on occasion).

My little mini-tour should tell me a lot. In a few days, I'll get to see if any of my speculation and theories panned out. If not, I may soon be trying to find ways to repair abraded powdercoat on racks.   Meantime, it'll be a chance for Sherpa to play in the snow and for me to check out the new kit in cold weather at 6,0000ft/1830m instead of 11,000ft/3350m later this month, and nearer home if something goes haywire and needs correction. See: http://www.oregon.gov/ODOT/HWY/REGION4/Video/242_open.wmv I like to set little quests for myself, and one for this trip is to find an old lodge built by the Civilian Conservation Corps around 1940. It has been neglected and is boarded up and barred to entry due to rot, but it would be nice to see if I can find it. As recently as 40 years ago, it was used as an overnight stop for hikers on the Pacific Crest Trail. I'll also see if there's fish at Fish Lake and stop for a moment at the John Craig Postman's Memorial ( http://news.google.com/newspapers?nid=1310&dat=20020516&id=slVWAAAAIBAJ&sjid=qOsDAAAAIBAJ&pg=2222,4390055 ) before heading back by way of Tombstone Pass.

All the best,

Dan.

[pdamm]

Dan

To get the pieces of rubber inner tube to stick to the rack I washed them thoroughly then carefully sanded off the outside layer of release agent before applying the contact cement.  So far the gluing has held up very well.

Peter

[StuntPilot]

Food for thought on this thread! Richie/Dan - you gave me an idea about the tubing, aquarium type or similar. I have the Thorn Expedition rear rack. I had a dig around the interweb and found a company in the UK (no doubt available locally internationlly) that supplies braided reinforced tubing with an internal diameter of 10mm, external 15mm. Sounded ideal. Link here ...

http://hotspecialoffers.co.uk/shop/index.php?main_page=index&cPath=15_12

They do other internal and external tubing dimensions which would suit other rack dimensions. Also clear tubing available.

First I cut the lengths to 65mm (for the Thorn Expedition rack) then cut down one side of each of the sections. I tried heating the tube lengths a little to make them softer and easier to fit and to try and get the zip-ties to sink into the plastic tubing for a seemless fit! Mistake - or I overdid it with the temperature and left a funny smell in the kitchen! No need as it turns out as the tubes fit the rack perfectly when you secure with the zip-ties. May add additional tube lower on the rack if there are any potential abrasion issues there.

Thanks to Cycling About - coupled with double pannier hooks and additional bolts ...

http://cyclingabout.com/index.php/2011/11/ortlieb-pannier-bag-tip/

Images below. First the pipe and 65mm lengths cut, then a view of the fitted pipe close-up and from above. The 15mm external tube diameter is a perfect fit for the Ortliebs without inserts (16mm). The tube seems very robust and is UV resistant and rated -20C to +50C.

I will report back on long term results in time.

[Danneaux]

Richard!

Wow! That looks so nice! There's something about the reinforcing grid that makes it look more "right" for the job than the tubing I've been looking at. A very nice, neat job, and I think you've found a very good solution.

The really nice thing about this is how you've filled all the spaces, so if the hooks did manage to somehow slide, they'll still reside in a covered area. I have a feeling the zip-toes (very thoughtfully placed head-down) will do a great job of snagging the clasping hook (the little one that retracts on the underside) and also keep the bag from moving.

There is yet another advantage to all you've done -- the rack surface itself (top-deck) will be protected from abrasion that could be caused by any rack-top load. You could put pretty much anything you wished on there...including more protective sleeves on the crossbars if you wished.

Well done! Thanks for sharing! Very nicely-taken photos, too.

Best,

Dan.

[richie thornger]

I knicked my idea from biciclown on youtube. I tried with zip ties but the snagging on the clips annoyed me so I went with tape instead.
I hadn't thought about heating the tube and getting the zip ties to sit "in" the hose though. Yes making it flush would be much better.
The search continues.

[StuntPilot]

Dan/Richie

Yes, thinking about putting some tube on the 'top deck' as you suggested. Plan to use an Ortlieb Rack-Pack with the rear Ortlieb panniers, so protection there may prevent abrasion of the rack as well as the bag as you say. Time will tell with the zip-tie option. Thought about some tube lower down on the rack 'verticals' too. Will try later.

It is a breezy cloudy day today with sun with a few showers so about to take a spin up a local valley.

[richie thornger]

Hi Richard/Dan Hows the hose/rack/pannier combo working out. Time has been a problem of late. My system has been working but its looking mighty tatty now.
Time for me to tape them up again before I leave on the tour. As my bike will have the panniers attached most of the time you cant see the nastiness underneath.

Did those saddlebag straps ever come your way Rich?

[StuntPilot]

Richie

My reinforced tube stup is wearing well. You should give it a go! I see you are off on a big trip and I am jealous! That will be me one day soon I guarantee!

Nope, sent you two messages, and no straps yet. Not a problem as I have attached my super tubing and the bag sits fine under the saddle.

All the best with the trip!!!

[Danneaux]

Hi, Richie and Richard!

I still have not come up with my "ideal" solution for the Nomad. After a lot of experimentation with Sherpa's racks, I can tell you what has not worked for me in my own circumstances and conditions. I have come to the conclusion Ortlieb's wrapper-tapes aren't for me. I found with heat (simulating what I often encounter in the desert, with stationary temps approaching 140°F/60°C), the wraps delaminate and start to curl, leaving sticky stuff behind.

The TrimBrite automotive trim tape is not durable enough under abrasion by the Ortlieb glass-filled nylon hooks. It did stay in place very well with its low-creep adhesive and is very tough in other ways and applications. Though not suited for racks, the Trim-Brite tape makes terrific rub strips to protect frame paint from cable housing.

Electrical tape has a high-creep adhesive that left a gummy mess on everything for me. It took a lot of work with 99% isopropyl alcohol and even some peanut butter and GooGone adhesive remover to get everything cleaned up. I tried cloth-reinforced duct tape (available in black), and that was equally disastrous; as soon as the "skin" covering the tape wore through, the adhesive was even tougher to remove.

I'm now nearly at the point of simply letting the Ortlieb hooks and stabilizers rub a bit and touch-up the paint upon my return. "Nearly", but not quite "there". I like Richard's idea and am giving it serious consideration; it looks very nice, indeed!

All the best,

Dan. (...who is still pondering)

[il padrone]

Most of the Ortlieb abrasion tape patches eventually fell off my racks under the heat, abrasion and dust of our recent Central Australia tour. My pannier racks have areas that have rubbed the powder-coat off to a fair extent. I am looking to get some plastic fuel-line tubing to protect the rack bars.

[StuntPilot]

Thought I would add some more pictures of the final rack protection in place.

I have now added a Mark V low-loader and put some of the same tube there too. Where the Ortlieb bottom hook contacts the rack, I have added some old inner tube as the reinforced tube is too bulky.

Additional cable ties have been added so that the pannier top hooks do not slide about. All in all the panniers fit well, do not move and do not rattle. Happy!