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Hey collective, so I'm trying to make a sick drop bar mountain bike and I want to run 4-pot brakes with drop bars. Can I straight up do this with Shimano GRX brifters and Deore 4-pots? What are my other options?
No SRAM please, I'm trying to stay out of the insane asylum.
I had My grx lever hooked up to a 2 pot xt caliper woth no problem. Hoses are the same size, or close enough that they worked. Not sure if the 4 pots have thicker hoses but if not it should work.
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Drop bar mtb is so 1990. Btdt. Do yourself a favor and just get some Jones H-bars
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All GRX Brifters:
-ST-RX815 (11s Di2)
-ST-RX810 (11 speed mechanical shift, hydraulic brake, Ultegra level)
-ST-RX600 (11 speed mechanical shift, hydraulic brake, 105 level)
-ST-RX400 (10 speed mechanical shift, hydraulic brake)
all these use the same hose, the SM-BH90 which is the highest level hose used all the 4 pot mountain brakes.
The combination of GRX drifters and 4 pots are not on the official Shimano compatibility charts.
BUT as an example the chart shows is:
XTR MTB levers will work with with Dura Ace 2 pot road, or XTR MTB 2 pot or XTR MTB 4 pot.
So my conclusion is the same lever pushes the same fluid to a 2 pot and to a 4 pot, so your GRX will work with 4 pot.
Thank you for the datapoints. Sounds like I should just try it out. At the very least it will work from a hook up point of view, perhaps I won't get the amount of force I am looking for though.Quote:
Originally Posted by Dee Hubbs
Second question, currently the bike has a Deore 10-speed RD and 10-speed 11-42 cassette. I know that the 10-speed Deore RD is not compatible with any of the drop-bar pull ratios.
My question is - what are my options to keep this 10-speed RD and 11-42 cassette? This is going on an e-bike so I would prefer to keep the 10-speed cassette. Obviously the easiest option would just be to go all 11-speed GRX but I feel that I'll probably wear everything out much faster.
1x10 or 2x10?
If you have it set up 1x10 I'd buy a GRX RD-RX400. ($60) Its officially capable of handling a 11-36 cassette. You can maximize the B-screw and it should shift into the 42. Maximised B-Tension might compromise the sifting on the 11t and 12t end of the cassette, but it will just be a little sloppy/slow.
Depending on your frame and hanger size/shape you might need a Wolftooth Roadlink.
1x10. That's what I was thinking of doing. I am running 11-40 using an Ultegra RX derailleur on a gravel bike now 2x11 and I get that sloppy shifting at the small cog end which is less than ideal but it is what it is.Quote:
Originally Posted by Dee Hubbs
If you are willing to consider an aftermarket option, check out the Hope RX4 calipers. Just installed them on my gravel bike and they have great stopping power.
^ I saw those but pricier than the Deore bits lol
https://www.wolftoothcomponents.com/...roducts/tanpan
Converts road ratio to mnt ratio. I used on skibee's (Mrs mntlion) touring bike for 5000+km. works great
I think ALL shimano brakes use the same fluid ratio, so seem to all be cross compatibly.
2 vs 4 piston
road vs mnt
old vs current.
Well that is a shocker. Tell someone at Shimano they better get right on changing that!Quote:
Originally Posted by mntlion
What is the intended use for a drop bars e-mountain bike?
Commuting. This thing will barely see dirt unless you count the bottom of potholes.Quote:
Originally Posted by PNWbrit
The why the fuck would you put 4 pots on it, you commute over a 2,000' hill? And why drop bars?
Burn it, and then delete this thread.
I'm betting he already has the 4-pots...and, it's his bike. WTF do you care?Quote:
Originally Posted by stuckathuntermtn
This might solve your issue: https://bikepacking.com/gear/surly-corner-bar-review/