Author Topic: LTWOO ER9 & ERX - Electronic groepsets  (Read 1480472 times)

lavistaa

Re: LTWOO ER9 & ERX - Electronic groepsets
« Reply #2205 on: September 17, 2026, 07:06:59 PM »
Is there anyone running the oversized pulley? I accidentally stripped the bolt hole on the standard ER9 derailleur cage and so had to get an oversized pulley cage replacement.

I'm running 50/34 and 11-34 Ultegra/105 and I'm having a problem where even after sizing the chain correctly and removing an extra set of link pairs, I'm getting a situation where on the largest cog (50 and 34) there is sufficient tightness in the chain/derailleur, but when I run the smallest cogs (34 and 11) the chain is completely slack. I know typically this isn't a combination that you're advised to run, but just want to make sure I haven't set up my kit wrong.

Any advice/feedback would be helpful.


Thank you.


I’m using one of those offset 18t pulleys and also an 11-36 with a 42/26 crankset and have zero shifting issues.   I believe if you turn on “gear protection “ in the app it will also automatically avoid this (bad) combo.

andrewbikes

Re: LTWOO ER9 & ERX - Electronic groepsets
« Reply #2206 on: September 17, 2026, 09:27:37 PM »

I’m using one of those offset 18t pulleys and also an 11-36 with a 42/26 crankset and have zero shifting issues.   I believe if you turn on “gear protection “ in the app it will also automatically avoid this (bad) combo.

Thanks Lavistaa. I plan to have gear protection on, but during my tune up of the shifting i wanted to go through all gear combos to double check there weren't any issues. everything went fine except for the chain slack on the 11 and 34 combo. Do you have much chain slack when you go 11 and 26?

jonathanf2

Re: LTWOO ER9 & ERX - Electronic groepsets
« Reply #2207 on: September 17, 2026, 10:16:03 PM »
Is there anyone running the oversized pulley? I accidentally stripped the bolt hole on the standard ER9 derailleur cage and so had to get an oversized pulley cage replacement.

I'm running 50/34 and 11-34 Ultegra/105 and I'm having a problem where even after sizing the chain correctly and removing an extra set of link pairs, I'm getting a situation where on the largest cog (50 and 34) there is sufficient tightness in the chain/derailleur, but when I run the smallest cogs (34 and 11) the chain is completely slack. I know typically this isn't a combination that you're advised to run, but just want to make sure I haven't set up my kit wrong.

Any advice/feedback would be helpful.

Thank you.

Switch out the jockey wheels to Shimano Ultegra upper and lower 11t wheels to properly clear the 11-34t cassette. That should get the cage to clear that setup with very minimal chain slack especially when using gear protection. You can also get the 18t OSPW with narrow wide teeth to clear that combo. That combo can even clear 11-36t.

andrewbikes

Re: LTWOO ER9 & ERX - Electronic groepsets
« Reply #2208 on: Today at 01:10:20 AM »
Switch out the jockey wheels to Shimano Ultegra upper and lower 11t wheels to properly clear the 11-34t cassette. That should get the cage to clear that setup with very minimal chain slack especially when using gear protection. You can also get the 18t OSPW with narrow wide teeth to clear that combo. That combo can even clear 11-36t.

Thanks jonathanf2, I'm already running the 18t OSPW that came with the new cage and trying to figure out if that's what is causing the excess chain slack at when using both the smallest cog and chainring. Would love to hear if you have any experience in running a similar set up to me and whether or not you had as severe chain slack as me or if I've stuffed up the installation (either not set the derailleur spring tension correctly or if my chain is still incorrectly sized).

Thanks.