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I'm thinking these tool-storage bottle thingies are a good idea, especially as my bike has mounts for a third bottle cage under the downtube
This thing is what I'm talking about: http://www.zefal.com/en/front-bags/311-z-box-l.html
The obvious question is what bottle cage to use. There is no need to use a normal bottle cage which allows the bottle to be removed at will. I'd like one that is much more secure and ideally straps the tool-storage thing to the bike. Kind of like a mini Gorrilla Cage I guess.
Any suggestions?
I've been thinking of getting something like this and a side access cage so it'll fit below my current bottle and cage.
This has a thumb screw to retain the contents.
https://www.arundelbike.com/product/looney-bin/
Cheaper options would be a strip of velcro, or a bungee cord
I have the tool bottle linked above - really good and managed to squeeze loads in.
I've got the [url= http://www.chainreactioncycles.com/sks-slidecage-bottle-cage/rp-prod54323 ]SKS Slidecage[/url] on my Mega - really secure.
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Specialized zee cage.
Although I find it scratches the he'll out of the bottle if that bothers you.
Elite Ciussi, squeezed a little, with added grip-tape. Does the job more than adequately.
I just use a normal bottle cage but if you think it's not enough get some sticky backed velcro and attach small tabs of that to cage and bottle.
Another option is to get a BeerBabe downtube bag. I've the smallest of these (300mm) and can fit a Topeak Mini Mountain Morph pump plus a whole host of tools and spares and still have room.
Just use a normal one as it's the same shape.
I've got one of those Zefal tool bottles linked above and it works fine with a bog standard bottle cage. Although I put mine in the cage mounted to the seat tube rather than under the down tube as per the OP. Would think a velcro strap would give enough security though.
Or if you have the space these frame bags from Decathlon are great. I use one on my Solaris and get a pump and tool roll in there and even a small pocket jacket.
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I have a couple of those ones that are like plastic bottles with a screw lid that just fit into a standard bottle cage. Work fine but find they can rattle a bit unless you can pack them pretty tightly - can also be a bit of a pain to fish out the stuff at the bottom of the bottle (usually the inner tubes) requiring you to empty the contents out onto the road side. A made of mine has one that is like a stiff sort of neoprene construction with a zip running down the side so you can get access to anything...a bit like a cylindrical pencil case. Seems like a good functional design. No idea what make or brand it is.
Forgot to put the link for the Beerbabe bag - https://www.beerbabe.co.uk/ourshop/prod_6230779-Downtube-Pack-various-sizes.html .
This is it on my Solaris
The bike radar review of the monkii cage concludes keep to smooth surfaces, so I don't fancy that thing
The Looney Bin could work, but I imagine $15 of the $25 is going to go to the advertising team...
Perhaps the simple answer is a normal sturdy bottle cage like with a big elastic band or strap, but under the downtube is a precarious spot
To potentially answer my own question, this thing looks sturdy...
http://www.blackburndesign.com/en_eu/cages/outpost-cargo-cage.html
I use a Blackburn mtn cage on the underside of my downtube for a tool bottle (the zefal modular one). My advice if you ride technical terrain, fit the cage with nylon screws rather than metal. I'd rather lose a cage and bottle than rip the rivnuts out of a carbon frame
There are zipped bottle cage tool cases on P-X for a quid at the mo. If you're buying something else...
I use a Topeak adjustable cage with a Zefel tool container.
See http://www.chainreactioncycles.com/topeak-modula-adjustable-bottle-cage-2/rp-prod68036
It has a button adjust for quick change to bottle and fine adjust screw to clamp an item in.
Do you think you could remove the adjustable cage from the fixed section on that? Might be just the thing I need if it does.
Nearly bought https://www.halfords.com/cycling/bike-accessories/bike-bags-baskets/topeak-mondopack-hydro-saddle-bag in their flash sale the other day, but it's quite tall, you need ~32cm clearance from saddle top to tyre/guard.