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Other Resources => Maintenance, Mechanics, & Tools => Topic started by: chinapal on February 25, 2025, 01:29:46 PM

Title: Problem with LTwoo RX rear derailleur position
Post by: chinapal on February 25, 2025, 01:29:46 PM
Hello,

I recently finished my first build with an TanTan TT-X34 Frame and an Ltwoo RX hydraulic group set (yeah :) ). I was able to adjust the shifting to an ok grade but I struggle with the position of the (rear) derailleur cogs. On the low gears the cogs of the derailleur are touching the cassette (see pictures)
The little screw that suppose to change the position of the derailleur ram doesn't have any effect (picture with red arrow).

I feel something is wrong but I don't get it.
Cassette is a SRAM force one.

Any idea how to solve this?

Thanks in advance and best regards!

Title: Re: Problem with LTwoo RX rear derailleur position
Post by: SirBikealot on February 25, 2025, 02:44:54 PM

The little screw that suppose to change the position of the derailleur ram doesn't have any effect (picture with red arrow).


Thats the case because you unscrewed it completly. Screw it inwards until the RD starts movin away from the cassette. A gap around 6-8mm should be the target
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: chinapal on February 25, 2025, 02:59:30 PM
Thanks but I tried that. Screwing it in didn't have any effect. I feel something with how it is installed might be wrong.
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: chinapal on February 26, 2025, 04:25:24 AM
Thank you Serge,
The brakes are zrace, so it is basically this set (but I ordered the brakes separately. Breaks are good and light (there's is a trave velo video on them) l. Bleeding was a bit funny as they have two screws for the oil (for unclear reasons) and non of my adapters out of two kits fitted (browed one in the end from a friend).
https://a.aliexpress.com/_EHwRE1a
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: hsaus on February 26, 2025, 05:49:39 AM
Thanks but I tried that. Screwing it in didn't have any effect. I feel something with how it is installed might be wrong.

Is the B screw pushing against the derailleur hanger? I haven't used the RX mechanical derailleur, but here's a Park Tool video showing a few examples:

https://youtu.be/meUQ-BiFL28?t=105
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: chinapal on February 26, 2025, 08:07:24 AM
Yes, the B screw pushes against the hanger but for some reason the ring where the B Screw is attached moves independent from the rest of the derailleur. So screwing it in moves only the ring. To my understanding the B screw and the rest of the thing should move together.

Title: Re: Problem with LTwoo RX rear derailleur position
Post by: Lewis_Stewell on March 21, 2025, 02:45:44 PM
Yes, the B screw pushes against the hanger but for some reason the ring where the B Screw is attached moves independent from the rest of the derailleur. So screwing it in moves only the ring. To my understanding the B screw and the rest of the thing should move together.

Can you take a closer picture so we can see what's going on with the b-screw?
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: chinapal on October 30, 2025, 02:23:24 PM
I eventually figured that the Ltwoo groupset wasn't compatible with my Cassette with 11-34. Changing to a 11-28 solved the problem.
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: Omi on November 05, 2025, 06:52:26 AM
I eventually figured that the Ltwoo groupset wasn't compatible with my Cassette with 11-34. Changing to a 11-28 solved the problem.
I had no issues getting my R9 groupset to work with a 11-34 cassette.
Title: Re: Problem with LTwoo RX rear derailleur position
Post by: 00Garza on November 05, 2025, 09:28:28 AM
I had no issues getting my R9 groupset to work with a 11-34 cassette.

This can be affected by frame design and chainline specs. Will work with some frames, won't with others. Groupset manufactures will show the most common compatibility as their max limit.