Chinertown
Chinese Carbon Road Bikes => Road Bike Frames, Wheels & Components => Topic started by: Dewa6975 on January 28, 2026, 08:10:46 AM
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Hello,
I currently own a 105 groupset but I am not satisfied by the braking performance (surely due my weight at 90kg...)
I am looking to uppgrade calipers while keeping shimano's levers.
Considering ZRACE XG4, 4 pistons as Tracevelo did a review on them but looking for other recommendations !
Thanks
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I currently own a 105 groupset but I am not satisfied by the braking performance (surely due my weight at 90kg...)
Are the brakes properly bled?
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Not really sure as I am not a professionnel but I did take my time and did everything I could to get rid of air bubles.
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IMHO a propper set up Shimano 105 disc break should have good stopping power even for big and heavy riders.
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Have you correctly done the "break-in" period ?
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Have you correctly done the "break-in" period ?
Yes I did progressive stops at 25, 20, 15 km/h while slighty pressing on my levers.
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You can check also Lewis Brake and their SL/SLR version. They have it for DOT and mineral oil.
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Depends what frame you got you could also get a 160 to 180 flat mount adapter they're cheap on aliexpress. I got one on my gravel bike. But yes a properly setup 105 brakes should have plenty of power. What rotors and brake pads are you using?
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Make sure you are using at least 160mm rotors in both ends, get ahimano freeze rotors, xt-ultegra or above range, that should be enough. Don't forget to run finned shimano OEM pads.
I'm a heavy rider too, one of my bikes uses magura mt8 calipers which have a progressive bite and high stopping power at the end of the range but pad clearance is not as good as shimano calipers.
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I have 105 rotors but Bucklos pads.
I have the standard 160/140 105 discs but will rather start by improving my disc before going all in.
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The easiest and most cost effective upgrade would be increasing the size of your discs. Galfer green pads are expensive but provide very good power too.
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Regarding your 105 calipers versus the ZRACE XG4 4-piston calipers, your Shimano 105 have 22mm pistons, versus the 2 per side, 16mm pistons in the XG4 calipers. This results in about a 6% greater piston surface area for the XG4 calipers. (probably within the travel/modulation capability of the Shimano lever.)
I have had a lot of frustrating experiences with the basic 4-piston "E4" 16mm based MTB version of the XG4 caliper. I thought that this caliper would work fantastic because it is about a 90% copy of the Hope Tech E4 calipers. Not! For some yet TBD reason, it appears that the E4 rear caliper is very difficult to bleed. Looking at the XG4 caliper, it appears to have the same layout for the pistons and pads as the E4.
Therefore, I don't recommend the XG4 calipers.
If all you are looking for is new calipers, as stated already, I'de look at the Lewis calipers, or perhaps the new Wheeltop 2 piston calipers.
From another perspective, my bikepacking gear and my weight dials in around 210KGs. I have had numerous brake issues over the past several years. Last year, I started using larger rotors on the bikepacker. 180mm rear, 203mm front. I immediately noticed much better stopping power and less brake fade, and I still had about the same lever modulation. You might also experiment more with pad compounds.
I would recommend trying this before changing your calipers.
1. Purchase a set of caliper adapters and migrate to larger rotors.
2. Research brake pad compounds, and install new pads at the same time.
3. Bed in the new pads and test how they work.
Note: Migrating to 4-piston calipers that have only 6% greater surface area isn't a guarantee that the new calipers will stop any better than the existing ones.
- Unless you know you are overheating your current set-up on a regular basis, and have either cooked your pads or rotors, I'd stick with testing larger rotors and pads first.
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Just get larger rotors and tweak your pads and call it a day. I think peak torque makes some adapters. I assume there are cheap ali versions as well. Experimenting with Chinese calipers mixed with Shimano levers isn't the safest imo. You can get a massive jump in performance by increasing rotor size alone
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I used the XG4 calipers for a short while and wasn't impressed with the braking power, tried different pads too. Also the bleed was not easy. Less initial bite than Shimano and just a little more top end power not enough to make me want to live with them.
I would probably change the Bucklos pads to Shimano and run larger rotors if I was you.
Here's the adapter I have
https://www.aliexpress.com/item/1005009438621605.html
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180mm disc rotors. Just get adapters and call it a day. Your 105 2 piston calipers are more than capable of stopping your body weight.
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Get galders pads and if this won't do the trick change rotors, I really like Mana rotors.
No need to go 180mm
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Get galders pads and if this won't do the trick change rotors, I really like Mana rotors.
No need to go 180mm
I disagree. 90KG+ body weight is published in numerous documents/studies as being the transition weight where larger rotors should be considered. (Terrain dependent and/or if you are a recreational rider, competitive, or aggressive descender.)
I typically weigh 90 to 95KGs.
I am running 160 rear and 180 fronts on my gravel bike, and was running 203 front and 180 on the back of my 29er hardtail, then recently put on a 203 in the back for some dual lever, dual rear caliper testing I will be doing this spring. My full suspension MTB. is running 203 front and 180 rear.
These days, most of my difficult riding/descending is on my 29er carbon hardtail. (2.0 low rolling resistance tires) I use my gravel bike primarily for forest service roads and asphalt, and where I know I don't have long steep high speed rough descents (42mm tires that beat the crap out of you on rough descents)
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Switched from Shimano 105 calipers to the XG4, because i had always issues with the 105er, probably leaking. I switched pads plenty of times - original Shimano with and without scinted metal, changed discs, burned discs with fire, used 100s of ml of IPA, always with very very limited success. In the end, the pad's also added up at lot ... but the sound of braking was so aggravating.
Now with the XG4 - the bleed process is much more involved than Shimano's, because the bleed port has no opening/closing screw, so it will leak oil after disconnecting the hose (watching a Hope RX video that seems to be the norm). I also needed to buy a bleed screw set because my previous Bleedkit set did had no compatible available.
Long story short, now the brake performance is much much better, a little squishy in the first like 30% (what others describe as less "bite"). It might also because my first bleed process was not that great to be honest, after watching a vid from Hope RX I would need to do things a little different. But anyways, still great performance after like 50% lever pull, being able to block the back wheel and slide again (was not possible with Shimano). Already like 2 months, a couple of hundreds km, my Shimano's would have degraded already at this point.
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Your piston seals were probably leaking. With contaminated pads braking performance will always be bad. I can lock the rear wheel with with one finger pretty easily on Shimano 9270 brakes.
I'm 76kg but still run 180mm front disc on gravel bike. I could perfectly use a 160mm but love the better modulation and ease of braking with the 180mm. I often carry stuff on my rear rack and fully loaded my system weight might be close to 95kg.
If I remember correctly how powerful the XG4s were with 160's, I would say Shimano is more powerful with the 180mm front disc. And the braking feel is much better, using CL800 rotors and resin pads.
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I have 105 rotors but Bucklos pads.
I have the standard 160/140 105 discs but will rather start by improving my disc before going all in.
Here is your problem. Shimano system is great when setup properly. Buy shimano REAL pads from Shimano, not AE.