Anyone with thoughts about this?

you can, i've run the hydro cable on these brakes through several different bikes and aerobars, the reason they didnt is probably because of hose length or the amount of time it would take to do it. Its not an easy process, much harder than standard cables, and bending/kinking the cable can cause the brakes not to work.

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Hmmm. I'll give it a shot then and see how it goes. It sure would be nice if it works.

Good luck, post some pics of before/after if you do get it. You're going to need a few new fittings for the brakes if you do it.

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So the mechanic building up my bike and installing the maguras tells me that routing the hydraulic line through the top tube is not going to work because the bend is too sharp once it enters the well and starts to progress through the toptube. I told him that this has been done before with success, but he insists it cannot be done. My frame size is 51cm and he's cited the small size as an additional complication. He said he tried it for 2 hours, but it just cannot be done even (with the fork removed) without kinking the line. I wonder if he's just being overly cautious? This isn't a tri-specific shop and I don't think he gets my strong desire to have the line routed this way.

My other question is if there might be a more flexible hydraulic line that could better handle that bend?

Pics of the routing I want.
http://forum.slowtwitch.com/...rum.cgi?post=5007331

Yes he is being overly cautious. He/or the shop owner or manager just don't want to take the time to do it and take the risk or eat the cost if he damages the hydro line. It's doable, but it does take patience. There are other lines, but not all are interchangeable, and I have yet to run into one that fits and is more flexible than what comes with the rt6 and rt8 tt

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Why don't you do just it yourself then? How much are you willing to pay the shop to work on your bike all day instead of serving 3-4 other customers with more routine needs? I don't even work in a shop, but I've done enough bike work and have a full enough tool set that I often get friends that come to me for wrenching help and sometimes I gotta find a way to convince them that what they're asking for is beyond a reasonable threshold of my time for just a 6-pack or whatever. Of course it's a little different when it's an actual business, but at some point they probably don't want your money that badly anymore.

As a matter of fact, this is the first time in my life I've not done my own work. This is also the first time I've had a bike with hydraulic brakes. I bought the bike from them, told them I had the brakes, and they said "hey, we can do that." I'm actually planning to pick up the bike today and try to run the line. It's my inexperience with these brakes that's holding me back. I don't even have a bleed kit.

route it and let them bleed it

Is there a rigid 1/4 bend that they can use to solve the problem? No cable kinks in that case.

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That's on par with most LBS mechanics. As someone else suggested, try doing it yourself.

Can you explain what a rigid 1/4 in bend is?

Worth reading the whole thing:

http://www.slowtwitch.com/Tech/Magura_RT8_brake_How-To_3490.html


Magura also has some good how-to youtube vids, with bonus English dubbing.

I did read that link. .. it was terrific. I even printed it out for the shop since I want site of they've worked with these brakes before.

Like a 90deg Elbow. Or even 45deg.

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Like a plastic or metal elbow? How would this attach inside the frame? This isn't s bike specific part, so I'd get it at a hardware store?

I'm not sure, just speculating. I'd wager that one of the (albeit smaller) benefits of using a Hydraulics/Di2 is routing in ways that are impossible with mechanical cables. Isn't there an L-shaped joint that connects the hose to the caliper? I would guess that with such an assembly to make the sharp turn inside the frame you would connect it at the lower headset bearing opening with the fork removed. Again, just speculating - I don't know much about Maguras.

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OK, fair enough. From the earlier description I got more of the picture you might be one of those customers with more unrealistic expectations that may not be worth the business, but if they sold you the bike that's usually more of a long-term relationship and worth maintaining.

running any joint type connection will probably be more of a hassle than help. you'd have to get a great fit and even then you risk fluid loss/leak. If you're just trying to run the hose by itself it is going to be tough without any guide. i have found it helps to take the hose to a brake cable and run the cable through. The semi-rigidity of the brake cable will give you more control of the hose to get it worked through the small holes, especially since you have no clearance to get your hands in the frame. a pair of needlenose, small surgical scissors, and tweezers are also useful tools to help you grab any part of the hose you do see. If you see the tip of the hose near and exit of the frame you can use another brake cable and push it inside the hole of the hydro hose to help guide it out more or align it with the cable exit in the frame. I've spent up to 90 minutes just running two hoses through an aerobar, with many near misses.

You can also pre-bend the hose to make it easier to make turns or angles, just dont kink it.

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So I got the hydro line run pretty easily. I fed the end of the housing that goes to the rear caliper first through the bottom of the headtube after I removed the fork. I then fished this end out through the hole near the seat post. Then I fed the other end up through the available hole in between the derailleur cables. This left a loop at the bottom of the headtube. I then carefully pulled this end while pushing the other end of the loop down along the top tube. I was prepared for a real pain in the ass, but this really wasn't tons of trouble.

The shop had already run the housing the traditional route, so I spent more time removing the fittings from the brake and removing the fork than I did running the line. My worry now is that the line now is not long enough since I had to remove the fittings on the ends.

Thanks for all the advice and tips. I'll post some pics when she gets finished up.

In case anyone decides to do this, I thought I'd add some pics of what things look like when all done. I did need to order a new hydro line, but it was well worth the $20 to do so. The steps I took in my previous post made this modification super easy. Maybe this helps somebody else.

i am hoping to reroute my brake through the top tube. when i detach the hose from the brake caliper will it leak every where? do i need to empty the system before i start tinkering with trying to run it through the frame? any tricks for getting it through the frame? thanks.