LTWOO ER9 & ERX - Electronic groepsets

[Mattpl]

Yesterday first rainy ride and groupset working without any issue FD and RD after changing batteries still work fine. So bat are really important here also

[Avalius]

Damn bleeding these brakes is a mess. Front brake failed to bleed multiple times.
Saw a 105 di2 group cheap around me and bought it. With all the fails, I'm gonna sell it and be safe :s

[boxof13]

Damn bleeding these brakes is a mess. Front brake failed to bleed multiple times.
Saw a 105 di2 group cheap around me and bought it. With all the fails, I'm gonna sell it and be safe :s

For me, it's actually quite the opposite. I have easier time bleeding the calipers, especially with the additional air port. I very much prefer L-Twoo's system compared to previous 11 speed Shimano. I haven't tried the new 12 speed system from Shimano, but I'd guess it's similar.

[zerstorer]

Damn bleeding these brakes is a mess. Front brake failed to bleed multiple times.
Saw a 105 di2 group cheap around me and bought it. With all the fails, I'm gonna sell it and be safe :s

Check if the olive was properly crushed? It was my first time doing it and it went very smoothly for me.

https://youtu.be/cRrPe0YbDpk?si=9sCbZqYjbrZgOQGL

[hsaus]

For me, it's actually quite the opposite. I have easier time bleeding the calipers, especially with the additional air port. I very much prefer L-Twoo's system compared to previous 11 speed Shimano. I haven't tried the new 12 speed system from Shimano, but I'd guess it's similar.

Agree, I've bled both Shimano 11-speed 105 (R7020/R7070) and L-TWOO eR9. I found L-TWOO to be easier, the threaded bleed port on the calipers results in less mess.

[Sebastian]

Damn bleeding these brakes is a mess. Front brake failed to bleed multiple times.
Saw a 105 di2 group cheap around me and bought it. With all the fails, I'm gonna sell it and be safe :s

Did you back off the tiny reach adjust screws in the brake levers when bleeding? They can push the master cilynder enough to block the oil flow when bleeding otherwise. You will still be able to push the oil through but with a lot of resistance and you won’t be able to get all the air out.

[Avalius]

Did you back off the tiny reach adjust screws in the brake levers when bleeding? They can push the master cilynder enough to block the oil flow when bleeding otherwise. You will still be able to push the oil through but with a lot of resistance and you won’t be able to get all the air out.

That was the issue, didn't know.. Saw it in the youtube video.
Thanks for the help guys.

[Serge_K]

That was the issue, didn't know.. Saw it in the youtube video.
Thanks for the help guys.

it's also written in the LTWOO instructions manual that comes with the group, from memory.

[Sebastian]

You're welcome. Happened to me, too. And to several others. You'll definitely remember it next time

[Avalius]

it's also written in the LTWOO instructions manual that comes with the group, from memory.

With this group my first reaction is always this forum than youtube and last resort the manual. Think I've got my priorities wrong ;-)

[amacal1]

With this group my first reaction is always this forum than youtube and last resort the manual. Think I've got my priorities wrong ;-)

I actually found the manual by Ltwoo to be fairly complete and helpful. That's kind of a surprise, I know.

[hsaus]

eR9 issue and fix

I had an issue with my L-TWOO eR9 groupset today that I later fixed. It was most likely user error, and I'm posting it here in case it could help someone else in the same situation.

tl;dr
Problem: The front derailleur wouldn't shift, but the rear derailleur shifted just fine.
Fix: Ensure both derailleurs are firmly plugged into the battery, by unplugging them at the battery end, and firmly plugging them back in.
Likely reason: Poor connection to the seatpost battery on the battery end, possibly caused by vibrations by being transported in a car.
Other plausible reason: Dodgy batteries.

Situation

I was going for a ride in the morning, and I loaded my bike (https://chinertown.com/index.php/topic,4952.0.html) in the boot (trunk for those of you in the US) of my sedan (saloon for those of you in the UK), lying on the side (NDS). The drive to the start of the ride took about 20 minutes. When I took my bike out of the car, the rear derailleur shifted just fine, but the front derailleur wouldn't budge.

I tried the following:

• Shift using the shifters
• Shift using the app
• Unplug the rear derailleur, wait 10 seconds, then plug it back in
• Unplug the front derailleur, wait 10 seconds, then plug it back in
• Calibrate the front derailleur using the app
• Adjust front gears using the app
• Change front derailleur high and low limits in the app
• Swap the gear shift responsibilities of the left and right shifters
• Try with one-touch shifting both on and off
• Try with gear protection both on and off
• Rear derailleur firmware update - was using version 0.1.1, no updates available
• Front derailleur firmware update - app reported current version 0.0 and latest 0.0
• Reset to factory settings - this reset all my derailleur position settings (which I fortunately had saved)

The only response I got from the front derailleur was when I plugged the front derailleur cable back in. It was a buzz reminiscent of Trace Velo's issue (https://youtu.be/32UDzOrqK2I?t=78s).

Other behaviour I noticed:

• The app reported 91% battery level.
• The app reported that I used the latest rear derailleur firmware version 0.1.1
• The app reported that I used the latest front derailleur firmware version 0.0. This was different to what it previously reported, which was 1.12
• The app would show that the front gears had changed when I used the app, but nothing happened.
• When I tried to adjust the front derailleur position for the large chainring in the app, the app showed a position of 0. This doesn't match what I saw from Trace Velo's video. The position for the small chainring showed correctly what I had set it to previously (12).

Other points of note:

• The app reports that I'm using model ES-R9001.
• The serial number on the rear derailleur starts with 250123.
• The battery holder uses coil springs rather than leaf springs to hold the batteries in place.
• I'm running the groupset as 2x11.
• I haven't ridden the bike in the rain or on wet roads, and I haven't washed the bike.

At this point I thought the rear derailleur was toast (which apparently was Trace Velo's problem in the end), but I decided to do a short solo ride anyway, with the front stuck in the small chainring. After riding for about 50 meters, I tried to change to the large chainring, and it shifted! Actually, it over-shifted, because I had lost my position settings when I "Reset to factory settings". So I stopped, put the chain back on, and tried to shift down. No response. The rear still shifted just fine. I then proceeded to try many of the steps listed above one more time, but no luck.

So I started riding again, and after another 50 meters of so, I could shift back to the small chainring. That was the last time the front derailleur shifted until I got back home, so put my rear derailleur position adjustments back as they were and did the ride in the small chainring. It was fairly hilly, so I could at least get up the hills!

After I got back home, the front still wouldn't shift. At that point, I wanted to check the connections on the battery end. So I pulled out the seatpost carefully, as I wanted to see what state the connections were. But as I pulled the seatpost slowly and carefully up and out, both derailleur cables came loose from the battery case connectors. I then plugged both of the cables into the battery holder, and immediate success! I could shift up or down without issue as before, and the front derailleur firmware now showed the correct version.

My main hypothesis is that I didn't plug the cables properly into the battery, and that the vibrations from being transported in a care shook them loose. Then when I started riding, the movement caused just enough of a connection to be established so I could shift.

Assuming that's the cause, does anyone have suggestions for how to better secure the cables at the battery end?

Another hypothesis is that the issue was caused by dodgy batteries in the battery holder. I don't have anything to support this hypothesis currently, apart from the fact that I'm using unbranded batteries from eBay (https://www.ebay.com.au/itm/256250808223). They've been charging fine, and the reported charge hasn't dropped much with each ride. Regardless, I now have a branded set on order.

I'll also keep this bike for shorter trips for the time being, and be ready to pull out the seatpost should the problem reappear.

[jonathanf2]

My main hypothesis is that I didn't plug the cables properly into the battery, and that the vibrations from being transported in a care shook them loose. Then when I started riding, the movement caused just enough of a connection to be established so I could shift.

Assuming that's the cause, does anyone have suggestions for how to better secure the cables at the battery end?

Another hypothesis is that the issue was caused by dodgy batteries in the battery holder. I don't have anything to support this hypothesis currently, apart from the fact that I'm using unbranded batteries from eBay (https://www.ebay.com.au/itm/256250808223). They've been charging fine, and the reported charge hasn't dropped much with each ride. Regardless, I now have a branded set on order.

I'd suggest either heat shrink plastic, hot glue or rubber cement. I actually didn't use any adhesive at the battery holder end for my ER9 build. I just made sure the cables were properly snug. I'm using bubble wrap packaging tied to a string to secure the battery holder inside my seat post. I just used the bubble wrap that came with the groupset. I'm wondering if this stuff makes for a better vibration insulator than using those fancy Di2 mounts? My cables on the FD/RD end are all rubber cemented in and I added coat of dielectric grease.

Anyways, I've transported my bike multiple times on a car bike rack and I regularly ride on rough surface roads. Also I'm using Ebay batteries as well with no problems.

[Serge_K]

That was a very long message to say: have you tried unplugging it and plugging it again?
You could work in IT support now, you know enough to fix 90pc of people's problems!

[jonathanf2]

Today I finished up a ride and I was cleaning my ER9 bike when it fell on the drive side knocking the rear derailleur. It was enough of an impact to bend the derailleur hanger and threw off my RD fine-tuning adjustments. I had to realign the hanger and then redo my gear fine tuning. Luckily I was able to get everything back in working order.

I'm at about 13,600 shifts with the ER9. Issues I've encountered so far is jamming the chain into the cassette (dumping too many gears without pedaling) and dropping the bike on the RD (throwing off indexing). Both issues fixed. Batteries are still in working order and front/rear derailleurs shifting properly. Let's see how long my ER9 will last!