I came across this recently. Extremely lightweight bottom bracket and cassette tools. (100g or so total for the cassette, bottom bracket and crank adjuster).

I couldn't find any review however.

Are they any good? The use case is to carry along on tour to deal with emergency repair (i.e. not a shop tool in constant use. I am willing to pay to get reliable lightweight tools but do not want to have to hope that they will not break on the first occasion.)

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UPDATE
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[based on comments below] I've ordered the WolfTooth tools (Hollowtech II handle + lockring socket). Will "Update 2" once I've received and tried them.

What are you trying to accomplish?

First of all, I have no experience with these tools so that's where I'm coming from. I'm a believer in buying bike specific tools as you need them and I'm a believer in doing my bike tuning and repairs at home. When I ride I generally just carry enough stuff to fix a flat tire or two and a good attitude regarding anything else that may occur. I have no interest in carrying a bunch of even light weight tools with me.

Secondly, How to you visualize yourself using these tools? Take the cassette lock ring tool, for instance. You'll still need a chain whip if you plan on removing a lock ring and, if you have torqued the lock ring anywhere close to the 30 ft/lb spec, I doubt you'll be able to twist it off with just your fingers anyway.

Cassette and Freehub Tools for Bicycles from Harris Cyclery On a tour this is all you should need.

Until mentioned here , most are un aware many small makers of specialty tools exist .
So, this is another .. Tools ? wolftoothcomponents.com

I've never used those tools, but if you need light weight they ought to suffice. Be aware that even the 7000 series aluminum is much softer than steel, so they will not stand up well to real shop use.

Short answer is "well prepared for travel in remote regions". I come from a sailing background where you learn to prep meticulously as your survival may depend on having the proper tools/spares.

Longer answer is : Tightening screws and bolts, fixing flats and replacing spokes are a given. Replacing spokes "may" require a sprocket tool. I do not see myself lugging every conceivable wrenches. Yet, I do not want the try-and-pray variety of tools that come with warnings that they may damage your frame and/or may not be capable of handling shop-strength tightened cassettes. I currently have a small ratchet that can drive an 1/2 inch square drive conventional sprocket remover (with a length of steel tubing to gain leverage - the zyklop mini is rated at 65N/m). Abbey bike tool's Crombie is an interesting option (120g I believe, and certainly able to handle most/all cassettes). Wolf tooth another, with the added bonus that the handle is a Hollowtech wrench (which may not be likely to be used, however). Abbey bike tools appears to have a cult-like following. Wolf tooth flies under the radar.

The really long answer will add : At this point, I would think that a BB tool is pretty far down the list of useful tools, just above a welding station to repair a broken stay... on the other hand, if the weight penalty is nil, better have it than not. (in the Wolf tooth scenario, the total weight of the sprocket tool + BB tool is roughly the same as the Abbey tools' Crombie. So it boils down to the relative effectiveness of the tools. FWIW, my current solution ("regular" sprocket tool + 1/2 square drive adapter + short length of steel tubing) weight 260g. Carrying my current Hollowtech cup and crank tool would add another 160g, i.e. quite a lot of weight for something that is very likely to gather dust. So, yes, I'll try to find if Wolf Tooth tools are any good.

p.s. 1 -- A short piece of aramid rope tied at one end to a chain (spare or removed from the bike for the task) and to the rim or some fixed object at the other end, makes a reasonable chain whip.
p.s. 2 -- Aluminium tools may in fact be superior to steel tools when they are used to drive aluminium/light alloy parts. What concerns me the most are (a) the depth of the sprocket tool as many sprocket removers use a pin to prevent slippage, and, to a lesser extent, the quality of the machining

I don't have any experience with the Wolf Tooth tools, but there is nothing in the design that makes me think it wouldn't be reliable for cassette removal.

I will say that I have the Crombie and it is an absolute pleasure to use. It's my cassette tool of choice even in the garage. I have the matching chain whip, which is great and convenient for storing the two together though as you note you wouldn't need that for travel purposes.

The two biggest advantages I see of the Crombie over the Wolf Tooth tool are the one-piece design and the fact that the round surface will feel better in your hand than the flat edge of the Wolf Tooth tool. Whether that outweighs having a bottom bracket tool is your call, though for remote touring/emergency use I would think having an extra tool is a bigger plus than convenience and feel. On the other hand I think you're a lot more likely to want to use the Crombie at home.

Maybe I should purchase the Wolf Tool for travel and ask Santa Claus whether or not I deserve a Crombie...

from what I see, people are happy with their Wolftooth stuff. I imagine those tools would work fine for touring, although I'm not sure how you would replace a chain whip

I toured with older technology . freewheels easier to unscrew .. Just brought the removal tool.
(& borrowed a Big adjustable spanner, when needed)

Build around a Phil Hub .. eliminated the weak spot, their strong axles never Break..


FWIW, I Read Of people using a Bunch of Zip-ties and attaching the biggest cog and the spokes together .

to not need a chainwhip.

see here. Certainly not for the shop, but should do nicely on tour.

I will (eventually) try with the kevlar strand included in the FiberFix kit and a spare chain.

I just brought another spoke from my wheel build.. so once I got the freewheel off I replaced the one spoke (Of-48)
and was done. fiber fix just adds a step.

They've got a Black Friday special on the dual sided Crombie SL and chain whip combo.

I saw but passed. Includes the non critical whip and the dual sided Crombie. I am longing for the single sided team issue