[fatesjester]

Hi all, I’m hoping someone here can help shine some light on some odd, semi-consistent behaviour I’m seeing with my hope brakes.

After a bleed I have brake that just ain’t right straight away. I’ve had this happen a few times: the brake will be super soft and almost non-working. It feels like it hasn’t been bled for years. After going down one descent, let’s say 1-1.5km worth of decent grade 4, it’ll be back to it’s usual firm and strong braking behaviour.

It then seems to stay firm after having that day, wheel taken off, put back on for future rides etc etc. But then I get it bled again after it does the exact same thing.

I can’t think of any logical reason for this but maybe I’m missing something obvious.

If anyone could shed some light on this I’d really appreciate it!

 

[Jayem]

Hi all, I’m hoping someone here can help shine some light on some odd, semi-consistent behaviour I’m seeing with my hope brakes.

After a bleed I have brake that just ain’t right straight away. I’ve had this happen a few times: the brake will be super soft and almost non-working. It feels like it hasn’t been bled for years. After going down one descent, let’s say 1-1.5km worth of decent grade 4, it’ll be back to it’s usual firm and strong braking behaviour.

It then seems to stay firm after having that day, wheel taken off, put back on for future rides etc etc. But then I get it bled again after it does the exact same thing.

I can’t think of any logical reason for this but maybe I’m missing something obvious.

If anyone could shed some light on this I’d really appreciate it!

I bet there is some air trapped at the caliper on the opposite side pistons. I did a bike trip earlier this year where I had no front brake when I built up my bike after traveling, I had a tiny amount of front brake and as I kept actuating the lever, EVENTUALLY I got some front brake, but IMO there was air in the system and I may have been able to get it transferred to the reservoir, but upside down or whatever the air would find it's way back to the caliper. I was able to do a bleed and fix it in the field, but one of the basic problems with the Hope bleed is you are attempting to fight-gravity to bleed them, as in you are trying to force fluid downhill, but air bubbles won't naturally go downhill. For the best results, get the caliper above the brake reservoir...but the hope bleeding procedure is just kind of screwy like this. Usually it's "fine", but the fact it works in reverse as compared to almost every other brake system does have some disadvantages and this is one of them. They do have procedures for removing possible air bubbles out of the caliper, but it's also easy to pop a piston out while doing this, it's just not a good bleed system IME and the lack of effectiveness counters the ease. The Jagwire Hope kit does allow you to thread on a fitting onto the caliper and traditionally bleed (caliper UP), but you still have to un-thread at some point and probably do a little "hope-bleed" at the end.

IMO, there's no way they are bleeding these at the factory with their hokey lever-bleed technique. They have to be using a vacuum bleeder of some sort.

In any case, soft lever is classic air-in-the-system. The bubble probably hides out at the caliper. Most of the time the suggested bleed technique works, but sometimes a bubble is stubbornly hiding out and they can be a bit difficult to remove with the standard/suggested procedure.

 

[fatesjester]

I bet there is some air trapped at the caliper on the opposite side pistons. I did a bike trip earlier this year where I had no front brake when I built up my bike after traveling, I had a tiny amount of front brake and as I kept actuating the lever, EVENTUALLY I got some front brake, but IMO there was air in the system and I may have been able to get it transferred to the reservoir, but upside down or whatever the air would find it's way back to the caliper. I was able to do a bleed and fix it in the field, but one of the basic problems with the Hope bleed is you are attempting to fight-gravity to bleed them, as in you are trying to force fluid downhill, but air bubbles won't naturally go downhill. For the best results, get the caliper above the brake reservoir...but the hope bleeding procedure is just kind of screwy like this. Usually it's "fine", but the fact it works in reverse as compared to almost every other brake system does have some disadvantages and this is one of them. They do have procedures for removing possible air bubbles out of the caliper, but it's also easy to pop a piston out while doing this, it's just not a good bleed system IME and the lack of effectiveness counters the ease. The Jagwire Hope kit does allow you to thread on a fitting onto the caliper and traditionally bleed (caliper UP), but you still have to un-thread at some point and probably do a little "hope-bleed" at the end.

IMO, there's no way they are bleeding these at the factory with their hokey lever-bleed technique. They have to be using a vacuum bleeder of some sort.

In any case, soft lever is classic air-in-the-system. The bubble probably hides out at the caliper. Most of the time the suggested bleed technique works, but sometimes a bubble is stubbornly hiding out and they can be a bit difficult to remove with the standard/suggested procedure.

Thanks for the great reply!

I noticed this issue first after I flew with my bike as well - a quick bleed by the bike park mechanics got it operational but really wasn't great either. Definitely sounds like you're onto it with the calliper air bubble though, but what an absolute **** of a problem to fix if you're right.

I did think it would be air, but just didn't make too much sense to me as to why it would disappear after a bit of heavy use on a trail, but who knows.

After this happened last week I frustratingly bought a set of Code R's to replace them. What do you reckon about replacing the Hopes with these? I've always been a Shimano man before switching to Hope's to try out the modulation side of things. I absolutely love the Hopes but not the occasional frustration might have pushed me over the edge to what sounds like more reliability/consistency. I'm certainly not married to them because I bought them though (got them at industry pricing so can always sell on for close to retail if needed).

 

[macduff]

Leave it over night with the brake lever pulled to the bars (rubber band to hold there) so there's constant pressure in the system. Next day slowly release the brake lever to try and burp the master, this is trick I use on my motorbike brakes that are reluctant to bleed easily. The theory is the air bubbles migrate up the line to the Master and where they burp into the reservoir.