Author Topic: LTWOO RX hydro sets  (Read 50784 times)

Sebastian

Re: LTWOO RX hydro sets
« Reply #195 on: July 05, 2023, 12:30:25 AM »
Install of GRT groupset went pretty smoothly but I’m having a hell of a time bleeding the brakes. The rear went okay, but the front I simply cannot get to develop any pressure. And I can’t figure out why! Fluid moves through in both directions when I push or pull it with a syringe. The only thing I can see is that the syringe adapter piece (that screws into the caliper port) leaks a bit during bleeding. But that was the same when I bled the rear. I’m using the ZTTO bleed kit.

Any ideas? Thanks in advance.

I’ve found that any remaining trapped air that just won’t move upon bleeding the brakes will eventually move upon riding the bike and repeatedly braking. I had a gravel build with some very stubborn calipers that I could not get the rear brake properly bled on whatever I tried. One ride across bumpy terrain and all the air was rattled free and it moved up to the lever so I only had to quickly rebleed it and done.

jonathanf2

Re: LTWOO RX hydro sets
« Reply #196 on: July 05, 2023, 12:29:31 PM »
Install of GRT groupset went pretty smoothly but I’m having a hell of a time bleeding the brakes. The rear went okay, but the front I simply cannot get to develop any pressure. And I can’t figure out why! Fluid moves through in both directions when I push or pull it with a syringe. The only thing I can see is that the syringe adapter piece (that screws into the caliper port) leaks a bit during bleeding. But that was the same when I bled the rear. I’m using the ZTTO bleed kit.

Any ideas? Thanks in advance.

Try putting the mineral oil funnel attached to the top of the shifter and pump the brake lever to get rid of any remaining trapped air. If no more bubbles come out, remove the funnel and seal it. Double check there isn't a leak either by the calipers or the levers. Then pump the brake lever again for as many times as possible until you feel the calipers engaging.

Honestly I find Shimano hydraulic brakes much easier to setup.

k2502915

Re: LTWOO RX hydro sets
« Reply #197 on: July 05, 2023, 05:08:20 PM »
I’ve found that any remaining trapped air that just won’t move upon bleeding the brakes will eventually move upon riding the bike and repeatedly braking. I had a gravel build with some very stubborn calipers that I could not get the rear brake properly bled on whatever I tried. One ride across bumpy terrain and all the air was rattled free and it moved up to the lever so I only had to quickly rebleed it and done.

This solved the problem! Turned the bike upside down and all different directions and then went out for a maiden voyage—front stiffened right up within ten minutes. Thank you!

Try putting the mineral oil funnel attached to the top of the shifter and pump the brake lever to get rid of any remaining trapped air. If no more bubbles come out, remove the funnel and seal it. Double check there isn't a leak either by the calipers or the levers. Then pump the brake lever again for as many times as possible until you feel the calipers engaging.

Honestly I find Shimano hydraulic brakes much easier to setup.

Thanks! Will try this in the future if need be.

coffeebreak

Re: LTWOO RX hydro sets
« Reply #198 on: July 05, 2023, 05:27:00 PM »
Open bleed port at the lever and attach funnel filled with mineral oil combined with a small rubber mallet to tap the reservoir as I pump the lever - that has solved stubborn air stuck in the system for me.

Sebastian

Re: LTWOO RX hydro sets
« Reply #199 on: July 06, 2023, 05:38:29 AM »
This solved the problem! Turned the bike upside down and all different directions and then went out for a maiden voyage—front stiffened right up within ten minutes. Thank you!

Glad I could help. Have fun!
I’ve found this to be more effective than tapping away on the bike with a screwdriver or rubber mallet. Riding will introduce vibration everywhere and the air will move up, especially under braking pressure.  A quick bleed of the lever then is usually enough to get a perfect bite point.

nukem25rs

Re: LTWOO RX hydro sets
« Reply #200 on: July 06, 2023, 07:33:18 PM »
has anyone experimented with opening the screw that says air on the hood or the RX? I'm swapping bars so I have to disconnect my hydro lines and shift cables anyways.. I figure i may give that a shot during the bleed. just dont want to make them irreparable..

kbike

Re: LTWOO RX hydro sets
« Reply #201 on: July 06, 2023, 10:27:18 PM »
Air screw is fine to use.
Here's how used the second (air) screw.

keep the caliper bleed valve closed.
Syringe on the hood bleed screw normally used for the cup.
Open and remove the air screw.
Push fluid from syringe very lightly. 
Fluid will come out of the air hole. So have towel ready.
Put air screw back on. Remove syringe and put bleed screw back on.
Clean any mess.

I have no idea how to use a cup on the bleed hole and open the air screw. 

Remember to unscrew the adjustment grub screw on the level anytime you bleed the brakes. So you fully release the piston to fill the valve. That way you have the best chance of getting the firmest feel. You may still need to tighten up the grub screw.

Bigal

Re: LTWOO RX hydro sets
« Reply #202 on: July 24, 2023, 06:43:31 AM »
Anyone know of anyplace you can just buy the shifters LTWOO RX 12 Disc 2x12s Road Hydraulic Disc Shifter .  I want to pair them with some purple brake calipers I also already have all the other components with cable actuated disc so I don;t need a full groutpset.

Thanks

00Garza

Re: LTWOO RX hydro sets
« Reply #203 on: July 24, 2023, 10:32:00 AM »
Anyone know of anyplace you can just buy the shifters LTWOO RX 12 Disc 2x12s Road Hydraulic Disc Shifter .  I want to pair them with some purple brake calipers I also already have all the other components with cable actuated disc so I don;t need a full groutpset.

Thanks

Lots of places on Ali are now selling separate parts. (Edited with correct link)
https://www.aliexpress.us/item/3256805350413726.html?spm=a2g0o.store_pc_groupList.8148356.19.37387b3cnic8ES&pdp_npi=3%40dis%21USD%21US%20%24253.01%21US%20%24149.28%21%21%21%21%21%402103231116902127912683014e4997%2112000033455651484%21sh%21US%21161706925&gatewayAdapt=glo2usa
« Last Edit: July 24, 2023, 10:34:31 AM by 00Garza »

xtract

Re: LTWOO RX hydro sets
« Reply #204 on: July 24, 2023, 12:18:06 PM »
I am having a lot of trouble indexing my GRT groupset. Is there anyone who can share a picture of the distance between the pulley and the casette they have set it up to? Or anyone knows anything I should know?

/Xtract

00Garza

Re: LTWOO RX hydro sets
« Reply #205 on: July 24, 2023, 02:39:08 PM »
I am having a lot of trouble indexing my GRT groupset. Is there anyone who can share a picture of the distance between the pulley and the casette they have set it up to? Or anyone knows anything I should know?

/Xtract

Have you seen Luke's tips and tricks on this video? Starts at 12:28

xtract

Re: LTWOO RX hydro sets
« Reply #206 on: July 25, 2023, 01:51:33 PM »
Have you seen Luke's tips and tricks on this video? Starts at 12:28


I do not think he says anything about shifting issues, or tricks. In any case, it seems that I might have messed up the shifter housing while installing it through the internal routing handlebar, because I have tried with an external cable and it did not take long until I got it right. After putting it back through the internal hose again, it does not shift properly (going up in gear, so releasing tension, which makes sense). So time to buy some decent shifter housing and try to install it without messing it up!

/Xtract

jonathanf2

Re: LTWOO RX hydro sets
« Reply #207 on: July 25, 2023, 03:07:27 PM »
I do not think he says anything about shifting issues, or tricks. In any case, it seems that I might have messed up the shifter housing while installing it through the internal routing handlebar, because I have tried with an external cable and it did not take long until I got it right. After putting it back through the internal hose again, it does not shift properly (going up in gear, so releasing tension, which makes sense). So time to buy some decent shifter housing and try to install it without messing it up!

/Xtract

I would try giving the shift cable a few firm pulls to take out any slack from the internal cable routing. That usually does the trick for me.

Bigal

Re: LTWOO RX hydro sets
« Reply #208 on: July 28, 2023, 06:26:42 AM »

abedfo

Re: LTWOO RX hydro sets
« Reply #209 on: August 02, 2023, 04:49:31 AM »
I am having a lot of trouble indexing my GRT groupset. Is there anyone who can share a picture of the distance between the pulley and the casette they have set it up to? Or anyone knows anything I should know?

/Xtract

I have the GRT also. It seems to index okay on stand and work okay for a ride but then just becomes a bit crap. Exactly same with sensah stuff in the past. Id install an inline barrell adjuster so you can make slight tweaks on the road.