I have Magura Julies on my bike - the nice little handbook thing says not to store the bike upsdie down.

Does this mean never turn the bike upside down or not for prolonged periods? What about when repairing punctures? Its a huge faff putting the rear wheel on if the bike aint upside down!

What's the point.

The point is that the air that possibly is now in the oil-reservoir in the brake-lever (and doesn't do any harm there as it's planned to be in that place) might go up if the bikes gets turned up-side down. And up on a reversed bike means into the brake hose or the caliper, as a result your brakes might be fading, getting spongy or not performing at all, and in order to have that surely settled you need to bleed them newly. Sure that's mroe messy than changing a wheel on an upright bike.....
Frank / Shimano

I usually find with my deore hydros that they feel pretty soft for 10-20 minutes after being turned upside down, but seem to get back to normal soon enough. And they work pretty well.

The morale of the story is if you do turn your bike upside down, test the brakes work properly afterwards to make sure they work before you head off to that tricky steep descent...

Yeah but it was still a pain in the arse when I was changing the tube on Saturday!

arse-ing about by the road side trying to get the wheel into the dropouts whilst rotating into place on the chain and getting the disc in place between the pads while the front wheel is trying to roll into the road. Maybe I was just making a bit of a poor fist of things (my first time on that bike and those brakes changing the back wheel!)

But isn't it the case that, as long as the levers are not pumped when the bike is upside down, this isn't a problem? I find that pumping my levers after turning the bike the right way around leaves my (Deore) brakes feeling fine. I *think* my Shimano manual suggests something like this but I may be wrong...?

To "The ones who's name is not to be mentioned":
I assume you addressed me with your question?
You're right, your manual says the following:
"The brake system may have some air bubbles inside the reservoir tank which are still there when the reservoir tank cover is replaced, or which accumulate in various parts of the brake system when it is used for long periods. The M525 disc brake system is not designed to be turned upside down, so if the bicycle is turned upside down, the air bubbles inside the reservoir tank may move in the direction of the calipers. If the bicycle is ridden in this
condition, there is the danger that the brakes may not operate.
If the bicycle has been turned upside down, be sure to operate the brake lever a few times to check that the brakes operate normally before riding the bicycle. If the brakes do not operate normally, adjust them by the following procedure."

Anyway it's all a matter of product liability, and nobody wants to have some unexperienced guy crashing. Anyway there's a structural difference, Shimano disc's do operate on high-pressure, whereas Magura's are low pressure up to my knowledge, so I assume they react differently and you can't assume one it works in both cases.

Hermione (äähh..... Frank I mean)

well i had my bike upside down overnight on friday to allow the oil in the forks to get into the bits it hadn't seen for a while :) i had read about using laccy bands to hold the brake levers on but in the end i just left it without doing anything and the brakes were fine the next day...definitely worth checking tho :)

Julies (and most other brakes) are fine inverted for the time it takes to change a tube. Didn't the manual say not to *store* it upside down? So that's what to avoid doing.

I only glance at manuals so I know it said not to ...... upside down whether the missing word was turn or store I dont know. I'll read it more thoroughly this evening...

Frank,

I was addressing my question to you - I was too slow in typing so other posts got in first. Thanks for your input - I didn't realise there were high/low pressure systems.

As has been said by others, it's nice to have some input from manufacturers on site like this.

LV.

Thanks LV, appreciate
Frank