Bleeding cura 4s

Scotty675

Cable thief
I put some cura 4s back on a bike today. I’m trying to get the lever to feel like a shimano ie quick engagement and firm feel. The bleed process is a bit shit in my opinion. I can get a firm lever with syringe connected but lose fluid when replacing bleed screw.
Brakes work fine am I chasing a lever feel I won’t achieve or are there tricks?
I’ve got shimanos, maguras and a set of TRPs I can get all of these feeling close in feel at lever
 

Oddjob

Merry fucking Xmas to you assholes
Check the hose connections are tight. Use the two syringe (I'm assuming you have the relevant attachments) method and take the caliper off the bike and lay it flat so the bleed screw is facing straight up. Similarly, adjust the lever to do the same.

Pump the fluid back and forth between the syringes, with the syringes upright so that bubbles rise to the plunger.

First disconnect the syringe at the caliper and apply a teensy bit of pressure so the oil overflows when you screw the bolt in. Then pump fluid into and out of the lever to get any last bubbles out of the reservoir. Disconnect the syringe, the reservoir should over flow as you screw in the grub screw.

Voila! Rock hard lever.

Sent from my SM-G970F using Tapatalk
 

Scotty675

Cable thief
Check the hose connections are tight. Use the two syringe (I'm assuming you have the relevant attachments) method and take the caliper off the bike and lay it flat so the bleed screw is facing straight up. Similarly, adjust the lever to do the same.

Pump the fluid back and forth between the syringes, with the syringes upright so that bubbles rise to the plunger.

First disconnect the syringe at the caliper and apply a teensy bit of pressure so the oil overflows when you screw the bolt in. Then pump fluid into and out of the lever to get any last bubbles out of the reservoir. Disconnect the syringe, the reservoir should over flow as you screw in the grub screw.

Voila! Rock hard lever.

Sent from my SM-G970F using Tapatalk
After bleeding, how far do you need to pull the lever before they engage?
I have the formula bleed kit and have followed this process (as per there video).
I can get a firmer lever when applying pressure to syringe after lever bleed but loose feel and a fair bit of fluid when removing syringe and replacing with screw
 

The Duckmeister

Has a juicy midrange
I'm not familiar with Curas, but if there is any stroke adjustment on the lever, back it out all the way to maximise master cylinder volume. Once bled, tweak the stroke adjuster in; this basically partially applies the brake.

Also, contrary to another post above, I'd suggest removing the lever syringe & closing off that port first, then apply just a little bit of pressure at the caliper to force-feed it while you close the nipple. Easy does it though, if you get too gung-ho you can close the pad gap too much, and possibly also blow past the reservoir bladder.
 

Litenbror

Eats Squid
I'm not familiar with Curas, but if there is any stroke adjustment on the lever, back it out all the way to maximise master cylinder volume. Once bled, tweak the stroke adjuster in; this basically partially applies the brake.

Also, contrary to another post above, I'd suggest removing the lever syringe & closing off that port first, then apply just a little bit of pressure at the caliper to force-feed it while you close the nipple. Easy does it though, if you get too gung-ho you can close the pad gap too much, and possibly also blow past the reservoir bladder.
Unfortunately @The Duckmeister Curas don't have a bleed nipple it's a screw you remove and screw a syringe fitting into.

They do have a stroke adjustment so you have to wind that all the way out and the pad clearance is tight to begin with so careful putting pressure into the system.
 

Scotty675

Cable thief
Unfortunately @The Duckmeister Curas don't have a bleed nipple it's a screw you remove and screw a syringe fitting into.

They do have a stroke adjustment so you have to wind that all the way out and the pad clearance is tight to begin with so careful putting pressure into the system.
They do run tight pad clearance that is for sure. The way the bleed process is I don’t think I could over pressurise the system while using the bleed block (ie I’m not quick enough to get screw back in) Never having run cura 4s I may be chasing a lever feel I won’t achieve. How do you find the lever feel compared to shimano?
 

Litenbror

Eats Squid
They do run tight pad clearance that is for sure. The way the bleed process is I don’t think I could over pressurise the system while using the bleed block (ie I’m not quick enough to get screw back in) Never having run cura 4s I may be chasing a lever feel I won’t achieve. How do you find the lever feel compared to shimano?
I'm running regular Curas and they are smoother than Shimano for me. You do have to pull more to get a hard bite but they do plenty of braking before that point. Shimano was tricky to feather the brakes where these are easy, with that comes a bit more pull to get full lock up. I did have to do a few bleeds to get the lever where I wanted it but I just screwed a Shimano cup in and did a quick and dirty bleed like that. It did firm up but like you I was coming from Shimano and I think I was chasing that feel. Now I'm used to them I would struggle to go back.
 

Scotty675

Cable thief
I'm running regular Curas and they are smoother than Shimano for me. You do have to pull more to get a hard bite but they do plenty of braking before that point. Shimano was tricky to feather the brakes where these are easy, with that comes a bit more pull to get full lock up. I did have to do a few bleeds to get the lever where I wanted it but I just screwed a Shimano cup in and did a quick and dirty bleed like that. It did firm up but like you I was coming from Shimano and I think I was chasing that feel. Now I'm used to them I would struggle to go back.
I’m just being fussy I think. I went and checked, with my shimano set ups pull the lever 20mm, with the cura pull the lever 50mm (Those numbers would equal epic fail and locked wheels on the trail) They worked fine last time I just didn’t like the feel at the lever. Way more modulation. Will give them another try
 

dirtdad

Wants to be special but is too shy
FWIW I've been wanting to try some degassed fluid in my cura 4s just to see if it can absorb any hidden bubbles. I also found last time I shuttled with a vertical rack my brakes needed a pump at the top. So I might hang the bike vertical before my next bleed.
 

gippyz

Likes Dirt
Mine very nearly got shimano fluid tonight. The formula fluid is very thin
I've been using shimano fluid on my cura (not cura 4s) for 2 years now and haven't had a single problem. I somehow managed to over-pressure my Curas and am regretting it now. They bite so hard with minimal lever pull that it scares me. All I did was injecting more oil into the lever until it's super firm.. I really need to reduce the oil content in the lever or else i'll kiss the ground from just braking and eventually sliding uncontrollably.
 

Scotty675

Cable thief
I’m now looking for a cura 2 to compare. I think the cura 4s just feel this way. The 2 and 4 share the same Master. Maybe this is the cause of different feel pushing 4 pistons?
 

Oddjob

Merry fucking Xmas to you assholes
I’m now looking for a cura 2 to compare. I think the cura 4s just feel this way. The 2 and 4 share the same Master. Maybe this is the cause of different feel pushing 4 pistons?
The 4 pistons will need a greater volume of fluid to move the pistons the distance. I haven't tried the Cura 2s but I know Shimano 4 pots definitely have more modulation than the 2 pots for this reason.

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Scotty675

Cable thief
The 4 pistons will need a greater volume of fluid to move the pistons the distance. I haven't tried the Cura 2s but I know Shimano 4 pots definitely have more modulation than the 2 pots for this reason.

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I think the problem is I’m after a shimano firm fast grabbing lever. These may not offer that and need to give them a bit more time. This time I’m running 2mm galfer rotors with galfer pro pads, hopefully that combo gives a little more initial bite.
Do you have any tricks for loosing less fluid when removing syringe, In my head this is half the drama

Note I am a bit fussy. I bought TRP slates to try, didn’t like shape of lever so fitted a shimano 9120 lever. Problem soled and they play perfectly
 
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