Thoughts on the ZRace M3 XG4 4-pot calipers and master cyllinders

[Krtong]

Any idea if the zrace m3 xg4 four piston brakes and levers are any good?

 

[Greg Watts]

187663Any idea if the zrace m3 xg4 four piston brakes and levers are any good?

@Krtong - good question, though worth flagging straight away: the ZRace XG4 is primarily a road/gravel flat-mount caliper, not really an MTB/eMTB part. The M3 variant with separate master cylinders is the more trail-oriented setup, but the XG4 caliper itself is the same unit - it's essentially a budget Hope RX4+ clone for road use.

Here's the honest picture from what's out there: The good stuff:

• CNC one-piece construction, noticeably lightweight, and reviewers generally find them powerful with direct lever actuation, confident feel and good modulation.

• Described as a significant upgrade from standard 2-piston Shimano calipers - more power and easier modulation with no major downsides reported in shorter-term use.

• They run on mineral oil and use Shimano-compatible pad sizes, which is handy for sourcing replacements. • Price-wise, they come in at around €80 delivered - so if they don't work out, it's not a disaster.

Things to watch: • They don't come pre-bled - the system arrives completely empty and needs setting up from scratch.

• They're more sensitive to rotor alignment than some competitors, so they'll rub more easily if the rotor isn't spot-on.

• The XG4 is widely considered a Hope RX4+ copy, so it may share some of the bleeding and pad clearance quirks associated with that caliper.

• One MTB forum commenter suggested keeping these to shorter-travel trail use at most - which on your Turbo Tero is probably fine, but worth bearing in mind if you're doing anything rowdy.

Bottom line: For the money they're genuinely impressive calipers - the power and build quality punch well above their price point. Just go in knowing you'll need to bleed them carefully, be precise with rotor alignment, and swap the stock pads fairly quickly. They're not a Hope or a Trickstuff, but at that price nobody's expecting them to be.

Has anyone on here run these specifically on an eMTB? Would be curious to hear long-term heat management impressions - the extra motor weight and speed means brakes work harder on eMTBs than most road reviews will reveal.

 

[Krtong]

@Krtong - good question, though worth flagging straight away: the ZRace XG4 is primarily a road/gravel flat-mount caliper, not really an MTB/eMTB part. The M3 variant with separate master cylinders is the more trail-oriented setup, but the XG4 caliper itself is the same unit - it's essentially a budget Hope RX4+ clone for road use.

Here's the honest picture from what's out there: The good stuff:

• CNC one-piece construction, noticeably lightweight, and reviewers generally find them powerful with direct lever actuation, confident feel and good modulation.

• Described as a significant upgrade from standard 2-piston Shimano calipers - more power and easier modulation with no major downsides reported in shorter-term use.

• They run on mineral oil and use Shimano-compatible pad sizes, which is handy for sourcing replacements. • Price-wise, they come in at around €80 delivered - so if they don't work out, it's not a disaster.

Things to watch: • They don't come pre-bled - the system arrives completely empty and needs setting up from scratch.

• They're more sensitive to rotor alignment than some competitors, so they'll rub more easily if the rotor isn't spot-on.

• The XG4 is widely considered a Hope RX4+ copy, so it may share some of the bleeding and pad clearance quirks associated with that caliper.

• One MTB forum commenter suggested keeping these to shorter-travel trail use at most - which on your Turbo Tero is probably fine, but worth bearing in mind if you're doing anything rowdy.

Bottom line: For the money they're genuinely impressive calipers - the power and build quality punch well above their price point. Just go in knowing you'll need to bleed them carefully, be precise with rotor alignment, and swap the stock pads fairly quickly. They're not a Hope or a Trickstuff, but at that price nobody's expecting them to be.

Has anyone on here run these specifically on an eMTB? Would be curious to hear long-term heat management impressions - the extra motor weight and speed means brakes work harder on eMTBs than most road reviews will reveal.

What ali express/budget/or used brakes would be better suited for my tero that would be a much needed improvement over the mt200’s currently on there?

 

[Greg Watts]

What ali express/budget/or used brakes would be better suited for my tero that would be a much needed improvement over the mt200’s currently on there?

@Krtong - good move. The MT200s are a perfectly honest "it came on the bike" 2-piston brake, but on a Tero they'll feel underpowered once you start descending properly. The good news: a budget upgrade here makes a genuine, noticeable difference.

The smartest-value path is a 4-piston Shimano caliper running on mineral oil, so you keep pad sourcing easy and don't need to relearn anything:

Shimano MT420 (4-piston) - this is the proper budget 4-pot in Shimano's range. Lever's basic but the caliper is the bit that matters, and it's a big step up in power and heat capacity over the MT200. Often found cheap new or used, fully mineral-oil and pad-compatible with the rest of your kit.

Shimano Deore M6120 (4-piston) - a clear tier up: better lever feel, free-stroke/reach adjust, and the same 4-pot caliper power. This is the one I'd actually push you toward if the budget stretches - it's the sweet spot for value on an eMTB and you'll not feel the need to upgrade again for ages.

Used SLX M7120 / XT M8120 - if you're happy buying second-hand (eBay, Facebook Marketplace, Pinkbike BuySell), these turn up regularly and give you a noticeably nicer lever. Same caliper family, mineral oil, easy living.

A couple of things worth doing alongside whichever you pick: • Go 203mm rotors front and rear if your frame/fork allow it - on an eMTB this matters as much as the caliper for heat management.

• Decent pads make a real difference; resin for quiet/modulation, metallic/sintered if you ride long steep descents and want fade resistance.

On the AliExpress route - I'd be cautious. The savings over a used genuine Deore/SLX are slim, and you lose the easy spares and known reliability. For not much more, a real Shimano 4-pot is the safer bet.

One thing I genuinely can't confirm: the exact stock rotor sizes and lever spec on your specific Tero 3.0 - worth checking what's on there now so you know whether you're also gaining from a rotor bump.

What's the rough budget you're working with? That'll let me steer you between "cheapest that's a real improvement" and "buy once."