GRX Sub-brakes
02-08-21, 05:09 PM
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GRX Sub-brakes
Hello everyone,
I recently setup a rig with RX600 with the Sub-brakes and I am having some issue with the braking at the RX600 lever. The braking power at the Sub-brakes is great, but I am having to pull the RX600 levers all the way to the bar with the paddle going beyond the bar. Basically if you are resting a finger between the bar and lever you aren't going to stop quickly without loosing a finger. Is this a problem anyone else is running into? This is my first time on GRX so I don't know if this is the normal performance for GRX or if this is an issue with adding the Sub-brake. I have tired multiple bleeds to fix this issue and advanced the brake pads slightly. Thanks for any info in advance.
Thanks,
Russ
I recently setup a rig with RX600 with the Sub-brakes and I am having some issue with the braking at the RX600 lever. The braking power at the Sub-brakes is great, but I am having to pull the RX600 levers all the way to the bar with the paddle going beyond the bar. Basically if you are resting a finger between the bar and lever you aren't going to stop quickly without loosing a finger. Is this a problem anyone else is running into? This is my first time on GRX so I don't know if this is the normal performance for GRX or if this is an issue with adding the Sub-brake. I have tired multiple bleeds to fix this issue and advanced the brake pads slightly. Thanks for any info in advance.
Thanks,
Russ
02-10-21, 07:21 PM
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These should be flawless so something is wrong of course. Did you do the install yourself? Have you confirmed all of the lines are appropriately tightened? Are you using the recommendeed bleed kit, tools and procedures? It may be time to take it to a good pro mechanic so you can get the real performance out of these you should be experiencing. Hopefully not a warranty thing as the warranty replacements are scarce for Shimano right now.
02-16-21, 12:57 PM
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Hey Russ, are you following the procedure for bleeding with the dual control levers in DM-GADBR01-01? It’s a test of patience and concentration; sure takes a while with 30+ steps. I installed mine a year ago, had to bleed the front twice but finally got them nice and firm at all the levers. Working great ever since, they are a nice addition.
Rod
Rod
