Dammit’s adventures in mountain biking

Ok, but- a slow leak shouldn’t stop me from being able to bleed the brake, that should happen and then fade as air gets in.

What if- this frame is internally routed, I can’t see maybe 70/80% of the hose. Could it be bent around inside the frame in such a way that it’s holding onto a pocket of air?

Maybe looped, and if I could get the hose straight that last pocket of air would come out?

Or am I misreading how a slow leak would present?

Stripped another bleed screw despite using a torque driver at the specified Nm.

Bled the system again. More failure.

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Cost benefit analysis.

How much do you earn per hour. How much time has gone into these brakes. Vs buy a set of shimano ones that will work.

Or am I misreading how a slow leak would present?

I had a leaky Shimano brake - you could bleed it and it would work for a bit but when left for a while it would contaminate the pads. I never saw the fluid but after several iterations of fix pads - ride - stand - dead brake, I binned it.

I it would be worth sharing the last 10 pages of this thread with Magura and getting a refund.

I think it’s certainly worth contacting them - they might offer a replacement. I’d either start isolating parts at this point or just replacing the entire brake.

Current issue is I can’t get the system to bleed correctly, but I can’t find any leaks. Whole new brake is on its way but I really want to know what’s wrong with this one- or if it’s my technique

but I really want to know what’s wrong with this one

It's fucked. Move on.

But what if the new brake does the same thing?

One thing that I thought was interesting is that if you don’t fit the bleed blocks the pistons stay exactly where they are during the bleeding process. I’d expected them to move.

With pads and a rotor in place the inside pistons don’t self adjust, which eventually leads to the calliper itself being pushed sideways until the inner face of the calliper contacts the disc- a net sideways force is exerted, basically.

Sticking this hex wrench in the calliper and operating the lever shows that once the outer pistons have emerged the inner ones will then do so.

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Bite point is still with the lever maybe 3mm from the bars.

It's fucked. Move on.

Or take it to a LBS.

This way if there’s an issues, they can resolve it.

It’s Easter Monday, I assume they will all be shut.

Some are open, abet a shorter times.

Whole new brake is on its way but I really want to know what’s wrong with this one- or if it’s my technique

At this point I’d be very surprised if it’s your technique. But - there is a trick to these when completing the final bit of work on the lever. It is possible to have it not quite full due to the angle of the lever at the point where the lever is sealed. which then shows itself later when you hit a bump and brake at the same time and it gobbles a load of air in to the line. Have a look at cutaways of the lever reservoir you should be able to visualise how this happens.

I have been fitting the bleed screw to the lever before the calliper, and making sure that the bleed port is full to the brim with oil before fitting the screw. Calliper body is horizontal when I fit the screw (or the oil leaks out).

The two pistons that extend have wet sides, the two pistons that don’t want to extend don’t. I lubricated all the pistons last time I bled this brake. Coincidence? Something to investigate?

Those are the fancy levers with various adjustments yeah?

Before doing the bleed process are you adjusting the lever reach/throw to the correct point?

I've never bled magura brakes but with my sram brakes you must set the lever to specific point.

Is it possible you're doing the bleed with the lever set incorrectly causing it to pull too close to the bar?

The lever is set to maximum reach, and maximum power. With the HC3 levers there's no ability to change bite point.

If the reach was any less then the lever would hit the bars before reaching the bite point. I've not played around with the power, but will do so now to find out what happens.

I'm out of ideas then.

This thread here might be worth a read.
Seems that following the official magura method doesn't work well for a lot of folk.

The third post talks about not pulling the lever syringe and only pushing fluid from the caliper to the lever. Maybe worth a try?

Turns out that the power adjuster on the HC3 does vary the bite point, so I’ve fiddled with that a little and combined with bleed #342 the lever is now firm and in the correct sort of area. The inner pistons are adjusting out and the outer ones are staying put- I’ll try re-lubricating the pistons tomorrow. Then throw the whole thing in the sea.

Sploosh

For reasons that should surprise no one I think that for this summers cycling trip I'll be going fully tooled up. Park Tools would cheerfully sell me what looks like a blue Peli 1560 aircase with a custom liner/organiser:

But it's not exactly cheap. That said, neither is a 1560 Aircase - and I don't think I'd be able to make an equivalent for what Park want to charge.

However, that's just one option - does anyone have a recommendation for a way to pack, transport, and crucially keep organised a large volume of decent tools?

does anyone have a recommendation for a way to pack, transport, and crucially keep organised a large volume of decent tools?

Just buy and take a second identical bike? 🤷🏻‍♂️ Old skool F1 style.
Might be worth changing the brakes to Hope / Shimano on the spare mind.

Peli 1560 aircase

I have one of these spare with new foams....

The rabbit hole is deep.