L-TWOO eGR Results Writeup

Installation and first impressions

Updates: 6/10/24, 7/4/24, 9/26/24, 10/3/24, 11/8/24

Background

I was interested in the LTWOO eGR groupset to use on my 2019 Salsa Cutthroat. It was running SRAM Force 1 HRD (Mechanical shifting, hydraulic brakes) with a Garbaruk 10-50 cassette and their cage extender to allow for that range on Force.  The setup worked, but I never had the reliable, crisp shifting I would have liked. Usually ended up 'finessing' each shift with partial presses etc. It was nearly impossible to find the right tension setting to get perfect indexing.  As my first 11s rig, I tolerated it as semi-normal for a while. Some of this is understandable given that it was modified outside of OEM spec. So I'm not badmouthing the Force itself based on that (for the badmouth, see this YouTube: SRAM Force 1 HRD (any DoubleTap) Shifter Spool Repair with Ratio Technologies part)

In building up a road bike this year, I found a great deal (Closeout D1) on a SRAM Force eTap 12s kit and decided to give it a whirl. It was a revelation. Easy setup on the first try. Fast, quick shifting. Never felt the hesitation of 'do I really want to shift now' like I had on the fiddly setup. So this got me thinking maybe the future IS in electronic and maybe I shouldn't be putting up with it.

But, upgrading to SRAM AXS on the Cutty was going to cost a fortune. Basically a full replacement mullet groupset less the cranks. Going mullet on SRAM requires AXS and requires 12s. So all parts of the drivetrain. Even at Rival/GX level the full kit of shifters, derailleur, chain and cassette (x2 as I have two wheelsets) works out to $1500 for the parts (50% more than I paid for the full 2x road gruppo). Budget buster.

I've been intrigued by LTWOO's entries into electronic shifting over the last year and a half. Good looking. Reportedly highly functional and an amazing price. And they are doing the right thing and allowing software configuration of the 'speeds' of the system (initially 10-12) which both SRAM and Shimano have refused to do and thus force full system upgrades.  The only downside were the reports of possible quality problems. I say 'possible' because on one side the reports were clear in the repetition from multiple reviewers of pre-release eRX units. But on the other side, it appears the later shipping eRX versions were not reporting these issues and the limited reports on the year-later eGR release were more limited.

But, the price was radically less. Basically the cost of a rear SRAM AXS derailleur and not having to replace 2 cassettes, chain, chainring from the 11s setup.  The one spec concern was the official limit of 46t cassettes and mine are 50t. But given that their other RDs go to 50 and at least one reviewer saying it 'worked' even if he wasn't happy with it along with possible hacks like a roadlink it seemed like it should be workable and less of a stretch than the stock 42t max on the current Force 1 RD.

All of this made for a compelling option to consider taking a flyer on and testing

Purchase and Installation

I ordered the 'naked' (no box, no fluids, no battery) kit via Aliexpress for the minimum price. It arrived in about a week, neatly packed in plain wrapping.  It looks great. Very nice fit and finish. The kit includes a full set of the 'stuff' needed to set up. Brake hose, end fittings, adapters, a variety of bolts etc. Nicely done.

Neatly and safely packed (but not the pretty display case)

But, going through the adapters brought about the first problem. While I had been told that the LTWOO calipers with the included adapters were meant for post mount, this is NOT correct. For reasons I won't try to figure out, they do not use a standard hole spacing. The mounting flanges LOOK like post mount but are only 70mm apart where post mount is 74mm. They also use M5 bolts and post is M6. 

The included adapters make them compatible with flat mount NOT post mount. As far as I could tell, nobody makes an adapter that would let them work. On the rear, it would theoretically be possible since my frame is set up for native 140mm rotors and you could make an adapter that would fit while also pushing out to 160mm spacing. But I don't think it would even be possible for the fork since it is native 160mm so any adapter would push it out (and 180 not certified).  I couldn't recycle the old calipers since they are SRAM and thus DOT fluid based. But I lucked into a local FBM seller with a pair of NOS Shimano BR-RS785 calipers available for a song. (and thanks to y'all here for confirming that they'd work with LTWOO levers). So, on with the build.

Build Notes

Brifters:

• Battery installation: The door is secured by ONE screw. The other end is hidden under the hood when folded back normally. This is a good thing but don't waste your time trying to get to the 'second screw (that isn't there) Shape markings are molded on the body to indicate the installation direction (nice). Be GENTLE on the screw as it is threading into plastic and never really 'bottoms out'
  
  
    

  
  
  
  
• I went a little crazy trying to get it into pairing mode. Instructions are clear but leave out one helpful detail: The pairing light is on the OUTSIDE of the lever and viewed in the crack between the paddles. If you are looking for it on the inside by the button like on SRAM, you won't see it light. Clear as day when you look in the right place.

App setup:

• 
  App setup was a little finicky getting it to find the master RD. It reported none to find when it was freshly awakened. Based on ongoing experience, it may be that the RD goes to sleep REALLY fast. So just jiggle the bike (or RD on the bench) again and it will work.
• The app opens in Chinese. If you can't read it, don't stress. Look at that home screen carefully and you'll figure out where to change the language to English. Sorry I didn't get a screenshot to share. I have a note about setting it up with just the email option, but I can't recall why. It's annoying that it is yet another app for local control that still demands a cloud login to work. But this isn't unique to LTWOO
• Oddly, it initially reported the RD as eGR Mountain Series (which doesn't exist publicly). But it now reports just eGR series. So things are changing.
  
• I set continuous shift to high. It's not so fast that you will be over shifting. I don't see any reason to run it more slowly unless you have problems. If you don't want it skipping across multiple gears, just block continuous shift.
• Giant miss for LTWOO: Both brifters have active shifting buttons. Not sure why since these are the gravel-specific models which are 1x only. Either left or right unit can control the rear derailleur (or the front if there were one). But you cannot set it to use either side (push wherever is convenient). Nor can you set it to run AXS style with upshift on one side and downshift on the other. I wrote to LTWOO and they confirmed this but left the door open for future software updates. They should absolutely allow both sides to be configured at the same time. Other modes or uses would be nice though.
  
  
    

  

Brakes

• 

  Front post mount caliper

  Notes above about the mount limitations with the LTWOO calipers. A shame I couldn't use them as they seem nicely made and look good. Note that while the kit comes with all the parts to install the LTWOO brakes (on flat mount), you will be missing a pair of crush bolts if you use different calipers unless you cannibalize the pre-installed ones that came on the LTWOO calipers. Getting them stalled my build.
• Setup and bleed is conventional Shimano style. Mineral oil. Open the funnel on the lever, and syringe at the caliper. Push from the caliper, draw back, repeat until the bubbles are gone.

• 

  Rear post mount caliper

  You MUST loosen the lever and adjust the screw. A tiny hole in the top front of the lever does it. If you do not, bleed won't bleed right. This is in the manual but it is not prominent. Also, you should maneuver the lever end to get different angles. Start with the funnel properly vertical. But also angle it and repeat to get a full bleed. Don't forget to tighten the adjustment screw again or you'll almost bottom out the lever. But tightened up, the travel is very short and firm. You can set it anywhere in between. The feel is quite firm and nice when set up.
• Shimano BR-RS785 installed
  
  
  

Wiring

• 

  Near side is the battery pack wrapped in heavy
  heat-shrink tubing, held in a pump
  bracket and secured with a zip tie.

  I had a special challenge on this one. The V1 Cutthroat was not designed with Di2 in mind and the LTWOO system could take advantage of such plumbing. There is no routing for wires from inside to out. Others have reported drilling holes in the frame for Di2 installations but I certainly wasn't going to be drilling a CF frame while experimenting. My solution was to use a minipump bracket to attach the battery tube beside the seat tube bottle cage. I wrapped the tube in heavy shrink wrap to protect it (and cover the stickers). I ran the wire under the left side of the chainstay/BB junction, across the bottom and out along the bottom of the right chainstay. Secured with zip ties and wrapped with self-stick silicon tape wrap for protection.
  
  
   

  

  Not the prettiest, but secure. Zip ties and wire covered in self-adhesive silicone tape (it doesn't use an adhesive to the frame just to itself)

  
  
  
  
• 
  There is a small arrow molded into the wire plug. It lines up OPPOSITE from the notch in the socket. When inserting, follow the directions and rotate with gentle pressure to find the alignment. But once pushing it in, there is a false bottom. Make sure you push it in far enough until you get a real, solid home.
• The battery tube has two housings for fittings like on the eRX kit apparently does. But for this 1x setup, there is only wiring in one of them. The other is blanked off. So no adding a front derailleur without a new tube.
  
  
  
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  You can charge and operate at the same time. Handy for initial bench test.
• I used dielectric grease in the junctions to increase water resistance. No issues
  
  
  

Rear Derailleur

• 

  Odd Hole

  Simple, straightforward installation. One odd hole in a place analogous to where the SRAM RD has the lock button. Not sure what it is for.
  
• The setup sequence works better if you remember to follow the directions. IOW, start with it lined up on the 6th (for 11s, 7th for 12s) sprocket and do the alignment setting. Do not start with the micro settings like I did.  In my setup, it was not naturally aligned and required an offset to work. But this is simple. Once you have established the baseline, the others are pretty close and individually tunable. In fact, they may have been correct if I hadn't messed with some of them first.
• Note that if you do micro adjust, there is a latency after each shift before the app shows the current micro setting for that sprocket. Wait for it to kick in before pressing or you will confuse yourself.
• As mentioned above, I'm running this out of spec with at 10-50 cassette. But after setting the B screw, the derailleur had no problem going from the 42 to 50t sprocket. The clearance is tight between the jockey wheel and cassette as it makes the transition, but once in place it is at spec.
• I was thoroughly pleased with the stand test. Quick, clean shifting each and every time across the cassette.

Initial testing

This write-up is very preliminary. I have shop-tested and taken it for a single, 16 mile ride so far. But the initial results are very promising.

• It does pair with a Garmin 1030 Plus and a Garmin 1040 as a generic electronic shifter. It will display gearing but does not appear to get recorded to the fit file. More research is needed. I was also able to pair it with a Karoo II but haven't run it yet. It is there, see 11/8/24 update
• It does throw a low battery error on startup on the Garmin. Checking in the LTWOO app showed 86%.  I assume it is simply not sending valid data. See 11/8/24 update
• Note that as far as I can tell, there is no way to check the battery status of the CR2032 batteries in the shifters with the app or a head unit. In theory, the LED will warn but I can't tell yet. The good thing is that with two controls, you could always fire up the app and switch which is operational.
• Shifting in the real world had low latency, was quick to complete, and was almost perfect. I had one 'skip' one time. Might have been a glitch. Might have been a gear where I need to micro adjust. A very nice experience that compares well to the SRAM AXS setup. (I don't have Di2 experience for comparison) See 11/8/24 update
• I have some sort of issue with the control paddles. I have bikes in most major shifting configs from downtube friction, through Shimano and SRAM mechanical AXS and switch between them with minimal mental overhead. But I find myself THINKING about which paddle to use here. We'll see how long it takes to develop muscle memory. The paddles are easy to differentiate with fingers. But with fingered gloves, it's hard to feel the difference and you have to rely on position.
• Braking performance feels good. Lever feel and modulation seems good. But I don't have experience with long descents or steep hills yet. Compatibility with the Shimano RS785 is very good and a good option if you need post mount. (See 11/8/24 update)
• Brifters are SMALL. They are much less beefy than the SRAM Force HRDs that I had before. They are even smaller than the 105 mechanical on another bike in the garage. Not good or bad necessarily, but definitely noteworthy.  The only downside is that I put them in the same spot as the old ones. But with less bulk, the top to bar junction has more of a dip vs a flat across kind of fit before.

What am I going to be keeping an eye on?

• Reliability. Luke on Trace Velo reported a mechanical break at the B-screw on his prerelease. Given some of the things he did at setup, it is possible that was a fluke and/or preproduction. I can't tell if my unit is designed differently.
• Battery life. Based on the initial drain, I'm not worried about the total charge lifetime. But with a single battery and no accurate status report, I do have concerns about how often I should charge to make sure I don't run out while on a ride.

Below you can see the shifting in action:

What have I observed?

• Battery life: In the first six weeks I've only put ~100 miles on it. (sorry, been doing more road riding this season)  I just recharged it for the first time because it was showing 38% and I didn't want to be surprised. 
• Based on the feedback during the charge, I'm not sure the indicators are right. This may be part my fault. The original spec batteries say they should be two 800mAh 14500 cells. But the ones I sourced are rated at 2500mAh. I don't know why the discrepancy. All the ones I found were rated 2k or above. But if the battery level circuit is expecting only 2x800 that could cause calibration problems. I'm curious is going full cycle will make a difference (The first charge was done externally to be ready). 
• Charging took longer than I expected. I went to bed at 4 hours with it showing 91%.  Funnily enough, in the morning, it indicated full charge (the cord light had changed from red to green) but when disconnected, the app reported 93%. 
  
• In conclusion, lifespan seems quite adequate at a minimum. I have to assume time is costing battery life in addition to miles/shifts. But so far, I don't trust the indicators.
• Update 9/26/24:
• Self-discharge: The system is draining at a non-trivial rate while sitting in the garage. Twice now, I've had a moderately full (40-50% ish) charge last I checked only to have it run out mid-ride within a week later. I don't have this problem with my AXS system. Now knowing this, I won't consider 50% to be adequate and just charge it then. Annoying but not a big deal. 
• Duration: A charge seems to last 1000-2000 shifts aka 250-500 miles based on a non-scientific analysis of the app counts at recharge
• Charging issues: Make sure you are actually charging. The cord base has an LED. Green means you are NOT connected OR you are charged. RED means it is charging. Ugh. I failed 2x in a row to get a charge by misinterpreting this. It is extra confusing because the magnet attaches and the small green LED on the derailleur flickers. Also the cord does not stick well. I have to arrange the wire to not apply force or it might disconnect.
• Water ingress: So far so good. I've now washed it a few times, including spraying the drivetrain with a hose.
• Shifting performance: 
• Very good. 
• But, I'm still convinced the buttons are backward (the rear, big one makes for harder/smaller gears and the tiny, forward one makes it easier. This hits my brain backward. Every time, I have to relearn. And I ride 8 different designs from SRAM, Shimano, and Campy without such issues. Thus why I think it is wrong and hope I'm allowed to reconfigure in an update. (My fantasy would let me use the big paddle on each side AXS style up/down and reserve the little paddles for auxiliary controls :-) (I think the first part might happen. I doubt the latter)  Update 9/26/24: As of the end of September, still no firmware updates of any kind
• I do recommend that if you are running an out-of-spec cassette like I am, to use the 'slow' setting on the repeat shift. Fast seems to increase the risk of the jockey wheel not keeping up and semi-jamming on the bigger cogs. In one-at-a-time mode and slow-auto it's fine.
• Ergonomics: The brifters are very skinny. For some people this will be fine or even good. For me, I prefer the chonky feel of Force D1 units or Shimano R7000 or even the delicate size of Campagnolo 10s. They are fine. The feel good otherwise. But worth noting. Update 9/26/24: I have mostly gotten used to it
• Reliability on the trail: So far so good. I did get some miles in on bumpy dirt trails at speed down in Santa Cruz. Zero issues. I heard no chain slap. The chain stayed on.
• App use: It's 'ok' overall.
• Some odd language use, particularly the dialog that wants me to 'confirm' the BT connection tip that I should restart it is odd. for example. 
• It does not seem to want to retain or restart BT connection while it is charging. Unfortunate but not a big deal. Shift count doesn't seem to be resettable.
• Update 9/26/24:
• Derailleur mechanical issue: The main pivot is not moving smoothly. Under certain circumstances, it creaks. When manually moved the 'stiction' is VERY high. Not sure if this means it needs some sort of service or just the way it is.
• Shifter button problem: The bigger button is sticking after application. So far, it is only annoying and doesn't impact function. A quick tap on the backside fixes it until it does it again. But it has me concerned about life
• Brakes: The braking system is actually excellent. To be clear, the calipers are not LTWOO due to fit issue mentioned above. But the combination of the LTWOO brake levers and Shimano BR-RS785 calipers works really well. Good, firm feel, progressive and powerful. Second best brakes I own (after some SRAM G2 RSCs on my MTB)
• Update 10/3/24
• Charging: It is ridiculously complicated to get the magnetic connector to attach correctly and stay attached. The slightest bump and it's gone. Combine this with the green light being a dual indicator of 'not charging' and 'charged' makes it necessary to use the app to verify connection and charge. 
• App Connect: I find the app connect to be super fiddly. Even moments after the last shift it will claim to not be able to connect because it is off. Sometimes it takes a few attempts at bumping or switching. Sometimes it actually requires finding the little tiny button on the RD to activate it. And the app doesn't retry. It fails, throws a modal dialog that must be cleared and you have to try again. Could be improved
• Worth noting, once I got it charged, it behaved perfectly on a major ride the next day. So...
• Update 11/8/24
• Brakes: I had the opportunity to test braking in the extreme on a 20 mile offroad descent recently. I have good and bad updates. The good: Strong, controllable and lasted fine. The bad: About a half mile into a steep trail with a lot of braking, I got some form of heat lock on the rear brake. Not a full lock but significant drag. No sponginess like with a bubble before or after. But the pads were being pressed into the rotor with enough force to slow me significantly. I'm pretty sure it was heat-related due to the heavy use and the fact that pausing for a couple of minutes and going easy on the rear brake for a few more and I had no problem the rest of the descent. There is still a firm feel when applying the brakes so I'm reluctant to try a bleed to fix. If you have other ideas, please comment below.
• RD Alignment: I've had single gears (#6 in my case) get out of alignment as evidenced by difficulty shifting into it in one direction. No idea what caused it. But a microadjust on the trail fixed it.
• Shift data: The information does appear to be in the FIT data. And due to the Garmin>SRAM connection I have configured, it shows up on https://axs.sram.com/activities. This is very convenient for me, but I'm not sure what one would do if one did not already have a SRAM AXS account set up (I have other AXS gear)
• Battery status in Garmin: The false information of 'critical battery status' is has been reported to LTWOO. This is a massively irritating bug. So long as the drivetrain is connected to the Garmin, you will get incessant, recurring, beeping alerts that the battery is critical despite the actual status. FWIW, it seems to recur on a longer cycle with the 1040