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Discussion Starter · #1 ·
Not sure how to really describe this, so here goes. Got a new bike, and it has Magura Marta SL's on it. Tonight was the virgin ride, and I noticed one thing about the brakes.

The rear brake only takes about half an inch or so of travel, before it locks up the rotor, however, the front brake takes nearly an inch of travel before it locks up the rotor. Same size rotors, front and back, new brakes, new pads, everything is new. The brakes were pre-bled by the bike manufacturer, from what I understand, because the brake lines were already cut to the proper length.

Is this a not enough fluid problem, or a bleeding problem?
 

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Discussion Starter · #3 ·
The levers stop at different points. I'm checking these while the bike is stopped. I'm not sure why the front brake lever requires more travel before it stops moving, versus the rear lever.
 

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It can't be taken for granted that the factory bleed is good, nor that the brake is properly installed. So, things to check (in order):

Caliper alignment (minus pads).
Bleed.
Lever set-up (refer to manual - downloaded from Magura if necessary)
Allow time for bedding in of pads/rotors.
 

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Discussion Starter · #6 ·
Ah, I think the reach may be more of the problem. I just bled the caliper, and did notice a few more air bubbles work their way out. It feels a little more solid now, and I bet the reach adjustment will fix the travel part of it, because I noticed the screw was not at the same position as the rear brake...
 

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One thing to remember, the rear brake has a much longer line. It will always feel a touch different compared to the front unless you have the BAT adjusted to compensate. Reach is just reach, it should be set based on your hands and riding preference, not to compensate for bite.
 

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Discussion Starter · #8 ·
Yeah, the reach was all the way out on both levers, so that wasn't it. I figured the levers would be somewhat different, but would have thought the rear one would travel more to full lock up than the front, since it has more brake hose... It could just be the slightly different caliper designs, one is IS mount, the other is post mount.
 

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Discussion Starter · #9 ·
Okay, back to the same operation, however, I have noticed something different.

When I squeeze the brake lever the first time after letting it sit for a long time, the lever goes almost all the way to the grip (about 3/8" before touching). If I pump the lever 15-20 times, it regains the original position of where it locks up the rotor, however, this is still a different feel than the rear brake lever.

I am thinking of bleeding it one more time, before I squeeze the lever, and see if I see any more air bubbles come out. Does this still sound like a bleeding problem, or something else?
 

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Discussion Starter · #11 ·
Yep, did that last time, and got every little bubble I could see out of the fluid. I think I found my problem though...

I proceeded to do another full system bleed, and found a few things out that made things easier than the last time I did it. This time, the bleed was successful, and I have an awesome, firm lever!

I also found that the hose connection to the lever was not very tight, so I tightened that up slightly.

The instructions say to hand tighten the hose barb/bleed screw adapter onto the caliper (the one that goes from the syringe to the caliper). I found, that while bleeding the brake, if you only hand tighten this connection, when you try and pull fluid back into the caliper syringe, it is really easy for that fitting to come loose enough to let air bubbles in. I used a small wrench, to just barely tighten it onto the caliper (just enough to keep it from coming loose).
 
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