Mudo 2.0 - Initial thoughts and evaluation

El Mudo ("the mute") out of Mexico by Manuel Larios, is the newest soloing device since the Silent Partner, Soloist, and Solo Aid to be designed specifically for rope soloing. Many devices are currently being used but they are all repurposed as soloing devices and used outside the parameters of their design and are usually expressively forbidden to be used for soloing by their manufactures. However many of us still use and modify them for that purpose. Now the soloing world has a new purposely designed and built device for rope soloing - El Mudo 2.0. It is interesting to note the similarity in form to the old Rock Exotica Solo Aid, though it did not self-feed and there other differences. I'm just noting the form factor similarity.

In these initial observations and tests I’ll compare the El Mudo to a GG3*/GG+* HUB set-up since that is what it most closely resembles in setup and function. Some might say it would be relevant to compare it also to the Soloist, however because it's no longer available (and I dumped mine years ago), I'll only mention it in passing. However, from memory, I'd say it very similar to the Soloist - maybe a bit more finicky in setting up but with equivalent performance, maybe slightly smoother feed with the added ability to easily lower/rappel. Lock-ups are also probably more positive from what I can remember with the Soloist.

The Mudo works by having a brake pivot that is inserted into the body and is secured by the security pin/axle. The rope feeds up from the bottom around the top of the brake pivot much like a bearing surface or pulley, then back down and out to the bottom rope anchor. The pivot brake is held up by a 'biner connected to a chest harness. This pulls the pivot brake up away from the body and allows the rope to feed freely. The brake pivot is somewhat "floating" in that the pin/axle is in an elongated hole in the body and because of the slot in the pivot brake, it is free to slide up and down and move slightly back and forth. During a fall or a high-clip the brake pivot is pulled down into the body and pivots and pinches the rope on both the leading edge of the body going in and the trailing edge coming out. This assures a secure brake on the rope and provides more contact area than the Grigri design which only pinches the rope in one place by the cam arm.

Feed                                                                             Lock-up

Before I go any further I'll summarize some basic stats and a summary of my impressions that will be detailed further down in the article. 

	El Mudo V2	GG3* / GG+* (with HUB cord*)
size	9.8 x 6.5 x 4 cm	10 x 6 x 4.5 cm
device weight	356g	GG3* - 176g GG+ - 201 g
climbing weight (harness attachment and chest harness attachment)	472g including 8mm cord and pear 'biner	GG3* - 286g GG+ - 311g includes maillon, HUB cord, and stainless clip for chest harness
cost	$140 + shipping	GG3* - $75-$88 GG+ $77-$140
harness attachment	8mm accessory cord or webbing**	8mm rated maillon or steel 'biner
recommended rope size	9.8-10.5 (probably could go down to 9.5 - needs testing 10.5 seems too big to me. Realistically, probably 9.7 to 10.0 is the sweet spot depending on the specific rope	8.5-11 (realistically 9.0 - 9.7 for LRS)
rope characteristics	flexible/pliable/smooth	flexible/pliable/smooth
device construction	all stainless steel!!!	seel/aluminum/plastic
construction assessment	super bomber - high quality - heavy duty	adequate - based on long history of use for LRS
lowering	add 'biner to use as handle to unlock and lower	integral handle: GG3* - super smooth GG+ - is a scourge because of anti-panic handle
high clip lock-up	yes	GG3* - yes GG+ - yes, but spring slightly delays
needs chest harness	yes	yes
chest harness attachment	round stock symetrical pear 'biner	needs mod: drill for 2.5-3mm cord and then use small stainless non-climbing rated clip/'biner
purposely designed and made for LRS	yes	no - must be modified and is beyond it's designed purpose and specs
needs cache loop	yes, for best feed	yes, for best feed
* GG3 with deactivated spring	https://sicgrips.blogspot.com/2022/08/deactivating-spring-in-grigri-3-for.html
* GG+ in TR mode
* HUB cord	https://sicgrips.blogspot.com/2022/08/grigri-3-hub-system-for-lead-rope.html
** see below for a way to rig to make it easy to put on/off
	FUNCTIONALITY*
ease of set-up	6/10	7/10
rope pairing	5/10	7/10
overall degree of confidence in device	9/10 (once set up correctly)	GG3* - 8/10 GG+ - 7/10
functionality for LRS	8/10	GG3* - 8/10 GG+ - 7/10
overal usability and ease of use	7/10	GG3* - 9/10 GG+ - 7/10
versatility	6/10	GG3* - 7/10 GG+ - 8/10
suitable for multi-pitching?	Possible but a bit of hassle - have to un-rig to add a TRS device. Best for cragging	Yes - but have to swap out for TR Solo device or pull rope while ascending
can be used for belaying up second?	no - only if belaying off harness and redirecting through anchor	yes - super easy to belay off anchor
can be used to belay leader or top roping?	yes - similar to an ABD feeding rope to leader takes practice	yes - purposely designed for (GG3* needs a bit of a modified technique) GG+ - dual spring modes
true auto lock-up belaying with hands off	yes	GG3* - yes GG+ - yes, in TR mode but not as fast/positive as GG3*
putting on / off / loading rope	Flat Fig-8 or Double Fishermens tie-in with 8mm cord - alternate attachment - see text	steel 'biner or maillon
feed while climbing **	good - dependent on rigging and rope. Takes some finessing to optimize but ultimately a smooth balanced feed	good - depending upon rope and rigging. Takes a bit of finessing with setting up and adjusting the HUB cord.
creep after lock-up	yes, depending upon rope rope-pairing is critical	no
high clip lock-up	yes	GG3* - yes GG+* - yes-slight delay due to spring
lowering	add 'biner to use as handle to unlock pivot brake and lower	GG3* - integral super smooth GG+ - is a scourge because of anti-panic handle
holds inverted falls	no - only with suggested supplemental Prusik/Kleimheist cache loop/backup	no - only with some type of backup
* This is my subjective impression and evaluation based on my limited use, the equipment I have and the methods described here and via the links. Further insight will be discussed in the review below.
** See the "feed discussion below in the review.

CONSTRUCTION

The construction is super bomber because of the stainless steel and the thickness of it. I don’t think there is any way that they device would ever break before the rope did. Some pull and drop tests could confirm that. In fact, I would think that future versions of it could be lightened by thinning the walls of the body by 25-30% and thinning and rounding off the excess material on the ends. Alternatively the body could be made out of aluminum. I personally would like to see the lightening holes in the sides of the body like v1 had. I see no reason how or why it would interfere with the function of it. Many ATC devices have lightening holes in the sides of the body (i.e. see the BD Guide)

SETUP 

The body is tied into the harness with 8mm accessory cord with a rethreaded flat figure-8 or double fishermen's bend. This is a bit of a hassle by contemporary standards but certainly effective and light weight and with no possibility of cross-loading. I suppose over time it will become easier to tie but certainly it is not user friendly for switching devices. An alternative setup that I came up with is to tie a loop with 5/8" tubular webbing with a maillon to secure the loop ends. This makes it easier to get on and off. The "price" you pay for this is the additional weight of the maillon.

I have also heard of another climber who used a large steel oval to tie is with and the 'biner went around both the waist belt and the leg loop strap. While NOT recommended by the designer, the user reported that it worked well, though one needed to make sure that it was free to rotate and slide on the 'biner. Also, when putting axle on/off, it is no longer held to the body (like with a cord tie-in). Therefore using a small dia. cord through the provided holes in the body and axle would probably be a good idea so that nothing is dropped when putting on/off. 

I had hoped that Petzl Omni might work because of the large diameter smooth curve which would be perfect. But alas, the cross-section diameter of the 'biner stock is too large to get through the Mudo hole tie in point. 

BRAKE PIVOT 'BINER

The 'biner used to hold the brake pivot up and connected to the chest harness in fairly finicky. I have found a lot of ‘biners that don’t work. Many ‘biners don’t work because: have too large a nose; I-beam construction that unpredictably hangs up on the "ears" of the brake pivot; cross-section of the ‘biner is too large (Dmm Oval) to fit the pivot; ‘biners with that are too slanting (too acute an angle); or having gate openings that are too small to fit the width of brake pivot, etc.

'biners that don't work                                                     'biners that work

In general pear 'biners work the best - especially those made from round stock. So far the one that works the best is a small old round stock Petzl Attache. Generally more symmetrical pear ‘biners work. Since it's only used to connect to chest harness and hold the weight of the rope for good feeding, even key-chain type aluminum 'biners can work. 

Best 'biner for Pivot Pinch Pin: Metolius Element or Attache; BD Pearlock; Rock Exotica Pirate; DMM Phantom; and Wild Country Xenon.

CHEST HARNESS

A chest harness is required for holding the Pivot Brake 'biner up. I did not test with a full chest harness but with both a Petzl Torse and an improvised chest sling made both with a length of 3/4" webbing or with two, 2' slings. I prefer those to a heavier dedicated chest harness since it's main function is to hold the pivot 'biner and rope up so that it feeds well, I found any of those to be adequate. Others may prefer a full chest harness. 

SETUP AND ADJUSTMENT

The adjustment and relationship between the chest harness, pivot 'biner, the Mudo body, and harness connection is critical for proper functioning and feed. It requires a bit of experimenting to get everything adjust so that it optimally feeds and locks up when weighted. The designer has stated that it is important to keep the body as close to the harness as possible. Using a cord to tie-in, this is somewhat difficult because of the tight access and space once the harness is and trying to tie and dress the knot. This may be one reason to use 3/4" tubular webbing and a maillon as shown above.

ROPES 

The suggested rope size ranges from 9.8 to 10.5. that are fairly new and pliable. From my limited experience of trying different ropes, I would think a new pliable rope of around 9.7 to 10.0 would be ideal. I didn't have access to one so I just had to try various ropes (10 of them) that I have from a new 9.4 Beal Stinger through to an old 10.2 Mammut Supersafe. Finding the right rope to maximize ease of feed and minimize creep is definitely a challenge - the device seems to be fairly finicky in my tests. Less forgiving so than my GG3* setup for sure. 

FEED/CREEP/BACKFEED

I found feed with the 9.4 and 9.5 ropes that I have to be wonderful and slightly better than than either of my GG HUB setups. However both are below the recommended rope size (9.8-10.5). At the larger rope sizes 10.0-10.5 to be too large for good rope feed. However, this really is dependent upon the specific rope. It's hard to make any generalizations.  I also found that the lock-up and high-clip was just as good the GG set-ups. 

HOWEVER, I did run into a sliding creep down the rope once it locked up. Creep ranged from ~5"/sec with a slick/pliable 9.4 Beal Stinger .5" second with an older 9.9 used fuzzy rope that feeds decently but still had some creep, though not as much as the 9.4. The 9.4 is well outside the suggested rope size limit so that is somewhat understandable. However I have a 9.9 which to me would seem an ideal rope size for the Mudo but it still had some rope creep which was annoying. Only large diameter stiffer ropes (10.2-10.5) had no creep. However ropes of this size didn't feed well in my experience. 

The whole rope creep thing is interesting because among other users some have found no creep while others have found almost as much creep as my smaller 9.4 but with a 9.7. I find it a bit annoying to start slowly sliding down the rope. It is easy to remedy by flipping a bite of rope around the free end of the Mudo body as shown below but should not be required when hanging on a rope. It will be interesting to see as others gain more experience what they experience as far as creep. At this point I find it perplexing the wide discrepancy that others have reported from absolutely zero creep at lock-up to almost as much creep as I've experienced. I have not experienced this with my GG set-ups using the same ropes. At this point, it remains somewhat of a mystery what exactly is the culprit since the results with different people and different ropes are all over the place. It does NOT seem to be the set up as I changed all kinds of variables in the waist belt and chest harness attachments and it did not seem to affect the results for me. It would be nice if they could sort this out and make the necessary modification before a v3 is released.

At one point I thought maybe the climber's weight has something to do with rope creep. I'm a lightweight at 125-130 lb which it seems would be counterintuitive as a contributing rope creep factor. Some heavier climber have not experienced the rope creep while others in the 175 lb range have experienced almost as much as me. It seems like it is more a function of the size/sheath weave/dry treatment/newness of rope/ and the pliability of it. Maybe the bottom line at this point is to find a rope that works like others have done with the Eddie and GG1 and then stick with that rope. Unfortunately, at this point, I don't want to have to go out and buy a new rope in the 9.7.99 range.

LOCK-UP

As I mentioned the Mudo locks up well whether a high clip or an actual fall, though I'll leave it to the young bucks to actually take whippers on it. At 71, I'm old school where the mind-set is that you just don't fall. I've tested it enough though to know that I can trust it should I have an unexpected fall. If you want a system that you can trust will catch you, I feel the Mudo is about as safe as one can be. I climb conservatively and if I get in over my head on a climb or get pumped out, usually I just just put a piece in and hang on the device. Thus the high clip capability is important to me. My real back-up is me: my experience: knowing my capabilities and climbing within them. 

INVERTED FALLS

A head first fall is a "weakness" of the Mudo, but is no different than a Soloist, or a GG and a HUB system. The chest harness pinning the solo device down so that is can't pivot independent of the climbers body orientation is the "culprit". For those who use this type of device, it is just part of the "cost" of doing business and one needs to take back-up precautions with any device held vertical with a chest harness. It should never be used without some time of good and reliable backup system.

CACHE LOOP / BACKUP

The owner's manual suggests using a combo cache loop and back-up knot/third hand consisting of a kleimheist/prusik loop attached around the harness waist belt on the back/side. This serves a dual purpose of maintaining a cache loop while at the same time maintaining a back-up knot that will pull tight when the cache loop runs out and act as a third hand to trigger the lock-up of the device. Or, when it runs into the body of the Mudo and stops the fall that way. This is a low-tech and innovative way to handle both. The down-side is that unless you have two hands free, you have to hold the rope in your mouth while cradling the Kleimheist in your hand sliding it along the rope to increase slack in the cache loop. This low-tech method could work well on any LRS device to serve the dual function of cache loop manager and back-up/third hand.

I personally. prefer to have cache loops clove hitched to 'biners on a reinforced gear loop as shown by (https://www.brentbarghahn.com/climbing-blog/redpoint-rope-soloing-2021). As you progress and the cache loop runs out you simply reach down and drop off another loop. See linked article for a full description. The benefit is that you don't have to muck around with hold the rope in your mouth and pulling the slack out and it's very quick and easy to release a new loop. The downside is you're carrying more weight on the waste belt of the harness.

Manual Larios also is developing a custom ATC type device called the Yomi which will allow you to pull slack similar to a Micro Trax but also locks ups like a ATC in guide mode should the cache loop run out. I’m looking forward to seeing and hearing more about it in the future. It could streamline the cache loop/backup process for the Mudo and other LRS devices.

I would love to see someone do some inverted drop tests with a full body weight dummy, both with and without the Kleimheist/Prusik to confirm that it will only lock up when the cache loop runs out. Could it be possible that the Mudo will lock without the back-up in a head first fall? I doubt it, but it would be good information to have knowing that most likely even in an inverted fall that it would lock before the knot came tight or hit the body. All this is conjecture till someone performs some actual drop tests to simulate an inverted fall. 

LOWERING / RAPPELLING

One main advantage that the Mudo has over the Soloist is that you can lower at any point in the climb by inserting a 'biner in the unused hole and pulling on it like a handle to release the Mudo which works well and gives a smooth decent. This is not quite as simple as a GG3 where you can simply pull on the handle to lower. However on the positive side there is no handle to get caught on any thing during a fall and hinder a lock-up. Just make sure you have a spare 'biner that fit the hole of the Mudo well.

CONCLUSION

Is the Mudo v2 a valuable addition to the world of LRS? I'd say it definitely is. It's no small task to design and manufacture a LRS. Manuel Larios has also shown a willingness to embrace feedback to constantly increase the quality and functionality of his product. Is it the right device for you? That depends upon many factors and how you rate and value those factors. Only you will be able to determine that. If you want a bomber device specifically designed for LRS and don't mind the initial setup, rope pairing of finding the right rope in the 9.7-10.0 range, the extra work putting the device on/off and also don't mind running some type of back-up for inverted falls, then it may be ideal for you. If you're a tinker and don't mind modifying a device that's not intended for LRS, want instant lock up with smaller ropes (9.0-9.7), then a GG3* costs less, are easier to rig and lighter and more versatile, then maybe that's the device for you. Functionally with the mods I've done, the GG3* is very similar to the Mudo. Most however will not want the added burden of modifying the GG and many will value the fact that the Mudo was designed ground-up for soloing.

If you're more concerned about inverted falls and want the device itself to be able to stop them itself (without having to rely on a backup system which you should have anyway), then the SP (extinct), Revo, or inverted Grigri setup may be what is best for you but they are outside the current discussion and they each come with their challenges also. There are so many factors and only you can decide.  Another good reminder: LRS is dangerous on potentially deadly no matter what device - choose wisely and no the strengths, weaknesses and how the who LRS works together. Ultimately YOU are the backup.

Suggestions for a future version

I would love to see the issue of rope creep solved. As I mentioned above, I don't feel that it is a show stopper but it is annoying. It could be that is will be like some other rope soloing devices where rope pairing is critical and that once you find a rope that works well, you stick with brand/size and replace regularly when worn. I will continue to experiment with different ropes and setups in hopes of finding something that will have no/minimal creep. 

I can envision a future version of the Mudo that would attach with a maillon/steel 'biner, that has a horizontal 'biner hole (like most devices) and has a side cover that pivots that rotates centrally around the axle like the Silent Partner. This would allow the brake pivot and axle to be permanently attached to the device and easily opened for slipping a bite of rope around the pivot brake, then rotating back closed and held closed by inserting a ‘biner through the body that connects it to the belay loop. This would eliminate the whole process of threading and and tying a rethreaded figure-8 rope, which would make it make it easier for multi-pitching. It would also mean there are not multiple separate parts to drop or get lost. Finally it would aesthetically be a nicer/simpler solution and also potentially lighter. 

I also think the body could be made with thinner walls or aluminum body. Either of these would lighten the device which I feel is over-built. 

It would be nice to have the "HowNot2" guys do some pull and drop test on the Mudo. I don't think there will be an issue with the device breaking, however it would be interesting to gather info re rope slippage. Slippage per se, is not dangerous and can even provide a bit of a cushioned stop. However, slippage beyond a certain point could be disconcerting and dangerous if it is going to significantly increase the length of a fall. Some devices are designed so specifically so that beyond a certain factor, the rope will slip. 

A side note regarding feed and back-feed. Ease of feed and back-feed are indirectly proportional. That is, the easier a device feeds (the more transparent it is while climbing) the more prone to back-feed it will be. Therefore the goal is a happy balance between the two. I think the Mudo has found that balance. It can be adjusted slightly by varying the angle of the body to the brake pivot which is controlled by how tightly or loosely it is rigged to both harnesses.

As always, these are my observations to date and YMMV.

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