Cyclist0108

I have some TRP full-hydrolic Hylex RS brakes. The calipers are the low point, so after several years of annoyance, I replaced them with Shimano BR-M6000 Deore Disc Brake Calipers.

I think I discovered the hard way that TRP's hoses are just different enough from Shimano's that they don't make a good seal. All was well for the first week, but now the brakes are weak, and I in fact discovered a very small but impossible to explain away quantity of mineral oil at the junction of the hose and the front caliper.

So am I just screwed, or is there any way to salvage this? (Anyone else stupid enough to even try to do this?)

gsa103

Did you use a new olive on the compression fitting?

Cyclist0108

Yes. (On both). I bought the Shimano versions.

CargoDane

Did you forget the small O-rings on the brake hose bolt?

https://www.google.com/search?client...4dUDCAw&uact=5

https://www.bike-components.de/en/Sh...e-Bolt-p39696/

Cyclist0108

I did not in fact use O-rings.

Are they required for the non-Banjo-bolt brakes?

I got the package with these parts (only):




I didn't know they even existed, or were required.

Oy.

Cyclist0108

BTW, my kid did the same thing with his mountain bike TRP brakes and these calipers, and it works flawlessly. He says he didn't use O-rings either. (He is now a much better bike mechanic than I am.)

What also worries me is that the TRP hose is 5.3 mm OD, and the shimano is 4.9. Could that be problematic?

CargoDane

Oh, that's up at the lever! I thought you meant the caliper down at the rotors:



From your picture, I can tell there are other Shimano olives (at least two different shapes). Maybe the shape is the wrong one (hard to know, since you don't use the same "system" throughout.
Also, the olive is meant to take some shape so it fits better when you tighten down the nut so it becomes tight. That's why it is brass (malleable). Did you tighten it enough?

CargoDane

That's a lot of difference for a compression fitting. So, yes, it certainly could be problematic.

Cyclist0108

I did. The caliper is different from the BR-785 pictured (which is essentially XT), and uses a banjo bolt. This one is more primitive, and also has the delightful design feature of no bleed port.

I'm using the TRP hose up to the caliper.



The hope is that I didn't, and it is simply a case of needing to wale upon it some more. OTOH, I wonder if I could have over-tightened it?

Cyclist0108

Yeah. That is what I am afraid of.

I wonder if the hose is wider than their mountain one. I will go check it.

Edit: He used Shimano hoses (5mm OD according to my measurement).

CargoDane

I don't think I've ever used a Shimano brake that didn't use a banjo bolt at the caliper. But since yours doesn't, no you don't need the O-rings. Try tigthening it a bit more to compress the brass. Otherwise, I think it's the vastly different OD tubing.

Cyclist0108

Yeah, the plan is now to tighten the living shi'ite out of them, and if that doesn't work, I'm going to install the Di2 ultegra levers (and calipers with banjo bolts and bleed ports) I picked up for $199 from Universal Cycle.

CargoDane

Good route to satisfaction, WG!

Cyclist0108

Except I will have to buy a battery, front and rear derailleurs, and have the frame drilled (or run it externally), or just use them as brakes for now.

It is a touring bike, so I am a bit reluctant to Di2-ify it, but if the situation forces my hand, who am I to ride against the wind?

Cyclist0108

My advice is to keep it that way.

They also use the cotter pin that comes with the pads, instead of a bolt.

They were $23 for a pair. I may have cheaped out.

Cyclist0108

This was the mistake. I should have used Tektro/TRP parts. Specifically, the barb thing was too narrow, and also the Tektro "olive" is shaped a bit differently. Tektro's lock nut threads into the Shimano caliper.

The Shimano barb was still loose in the tube when I pulled it apart. I had to tap the Tektro version of it in lightly with a ball-peen hammer. I suspect it requires the tight fit not to slowly ooze fluid. I used the other Tektro parts for re-assembly as well.

It is too soon to declare victory (the other problem took a few days to become apparent), but in retrospect the loose-fitting Shimano barbs should have been a tip-off that they were incompatible with the TRP brakelines, i.e., the TRP hydraulic hose ID > Shimano ID.

Here is what the correct fittings look like:

CargoDane

Yes, it needs to fit tightly. With the better fitting parts, I wouldn't have any worries. I'm certain you won't have any problems with the better fitting stuff. Good to hear you're where you are

Cyclist0108

Well, there is still no guarantee that mixing calipers and levers like this will work properly.

But at least now it has a fighting chance. I'm posting this mainly in the event that someone else is stupid enough to try it.

mtbikerinpa

I am curious on a similar vein, I just picked up a set of Hylex for $10 so I am not out much either way. I want to put a set of GRX sub levers inline to duplicate the dual brake lever position options that I have in my mechanical setup. I know bleeding is fun with them as I am Shimano certified, but nobody published attempting the combination yet. If it can be done with just interrupting the line and adding more terminations that would be lovely.

Polaris OBark

The main issue is the inside diameter of the TRP hose differs from Shimano. I have no experience with the in-line levers, but the critical thing would be the interface with the TRP tubing.

Where did you get them for $10? That is quite the find.