Removing and refitting hydraulic brakes?

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deliquium
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Removing and refitting hydraulic brakes?

Post by deliquium »

What's the most sensible method of removing hydraulic brakes from a bike - and refitting them after a respray?

The hoses are run internally. The levers are flat bar.

My initial thought would be to detach the hoses at the levers. Plug the hoses somehow so as not to lose all the fluid. Remove calipers with plugged hose attached. Wedge pistons to prevent movement. Allow the levers to drain? Store calipers and hoses vertically with calipers lowermost.

Then to refit by threading hoses through frame and grommets. Bolt on the calipers. Attach hoses to brake levers, top up with fluid and partially bleed?
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peetee
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Re: Removing and refitting hydraulic brakes?

Post by peetee »

DOT fluid or mineral?
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Paulatic
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Re: Removing and refitting hydraulic brakes?

Post by Paulatic »

Doing a rebuild I’d drain the lot and put in new fluid. There’s not a huge quantity involved or worth saving.
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rareposter
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Re: Removing and refitting hydraulic brakes?

Post by rareposter »

Remove brake pads - there'll be brake fluid potentially dripping out and the last place you want it is on the pads!
Don't worry about saving any of the fluid, it's far easier to forget about that and get rid of it. Use a rag to soak it up, there's not a huge quantity in there. Do NOT flush it directly down the sink!

Remove the hoses from the caliper end - depending on what brakes they are there might be olives and barbs in there or it might be a simple nut or it may involve cutting the whole hose off. Squeeze the lever a few times to force the fluid out into a rag.

Remove the calipers and hang up for them to drip dry. Note the position of any spacers, washers etc and save them with the calipers.
Remove the brake levers from the bars and pull the hoses out with them. Give the levers a few more pulls to force out remaining fluid and then coil the hoses up.

Refit is the opposite. Calipers on first, then brake levers, then thread the hose through the frame and reconnect - you may need new olives/barbs etc depending on the brakes. Pads back in and once the bike is fully built, the bleed is the last thing.
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deliquium
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Re: Removing and refitting hydraulic brakes?

Post by deliquium »

Thanks folks 👍 Cheapo, but been impressive and faultless this last year, mineral Tektro :)
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PH
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Re: Removing and refitting hydraulic brakes?

Post by PH »

I'm not sure about leaving the levers and calipers dry, does the fluid leave a residue when it dries out? It isn't the same as a new component that's never had fluid in it. I'm not saying it'll cause problems, just that it's something I'd want to know before doing so.
I'd also use new olives regardless, they're only pennies and I consider them single use.
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