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[Closed] Alternative disc calipers on GRX levers

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[#11650448]

Just out of interest, has anyone tried using a different make of disc caliper on Shimano GRX levers?

I can see that I can buy some Hope ones for nearly double the price of GRX ones but is there any other alternatives?


 
Posted : 01/01/2021 7:05 pm
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Im pretty sure someone will be along to tell you to use mtb calipers. However i dont think mtb do flatmount.

Mrs B has some Hope rx4 and loves them


 
Posted : 01/01/2021 7:16 pm
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Just noticed that the RX4's are 4-pot, I've never used anything but 2-pot in the past. I'm interested in these especially as I can get them in (controversial) purple. 👍 The price is a bit high for me but maybe I just need to save up 😣


 
Posted : 01/01/2021 7:24 pm
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I've got Ultegra post mount on my GRX810, works fine.


 
Posted : 01/01/2021 8:08 pm
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I have RX4s, they are awesome.


 
Posted : 01/01/2021 8:13 pm
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I've been using RX4 calipers on my two ebikes and they've been great. Almost 2 years in and no issues, bled once a year.


 
Posted : 01/01/2021 8:17 pm
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has anyone tried using a different make of disc caliper on Shimano GRX levers?

I’ve got Ultegra post mount

Who makes Ultegra?


 
Posted : 01/01/2021 8:32 pm
 four
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Shimano make Ultegra


 
Posted : 01/01/2021 8:40 pm
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Alternative disc calipers on GRX levers

😜


 
Posted : 01/01/2021 8:42 pm
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If they are Di2 levers hopes won’t work just a heads up.


 
Posted : 01/01/2021 8:48 pm
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Why's that then @wookster?


 
Posted : 01/01/2021 9:01 pm
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I honestly don’t know mate. I’m guessing it could be to do with the “servo wave” set up on the levers but I might be talking rubbish!! But GRX RX815 Di2 GRX RX817 Di2 are listed as not currently compatible.


 
Posted : 02/01/2021 12:44 am
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I also have Hope RX4 callipers with GRX levers (non Di2) and think they are excellent. Stopping power is good but the big win for me was the ease of set-up and much less grinding noise as they seem to have a bit more clearance between pads & discs.

They look ace too!


 
Posted : 02/01/2021 9:09 am
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XTR trail should work, and they come in flat mount, I think


 
Posted : 02/01/2021 9:59 am
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@wookster - I’ve been using RX4s and 815 Di2 levers for 10 months on one bike and 8 months on another with no issues in a combined 8000km.

I know that Hope say it doesn’t work, and I even emailed them asking why (no response) but they do.


 
Posted : 02/01/2021 10:05 am
 PJay
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It looks like SLX have a flatmount option too -

- if you're after a less pricey option.


 
Posted : 02/01/2021 10:05 am
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@didnthurt - why are you looking for different callipers?

Most folk go Hope when/because Shimano develop microleaks and start howling like a banshee in all conditions and lose any ability to stop.


 
Posted : 02/01/2021 10:07 am
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The grx di2 levers have a different pivot point in the lever to make braking from the hoods better, maybe this changes the braking in such a way that hope aren't happy with it.


 
Posted : 02/01/2021 10:56 am
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What Daffy said about leaky Shimano calipers.I might have an issue with my GRX400 calipers (GRX600 levers fyi).

Shame that magura don't make a flatmount caliper as my magura mt5's on my mountain bike have been great.


 
Posted : 02/01/2021 12:12 pm
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@Daffy Ah now that’s good to know mate! Nice one!


 
Posted : 02/01/2021 12:16 pm
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Just noticed that the Hope RX4 rear caliper is only compatible with a 160mm rotor, I have a 140mm rotor. Does this mean I'd need to get a new rotor as well?


 
Posted : 02/01/2021 12:20 pm