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Other Resources => Component Deals & Selection => Topic started by: Tijoe on November 28, 2025, 02:46:20 PM

Title: Frog Wake FV4 MTB Brakes
Post by: Tijoe on November 28, 2025, 02:46:20 PM
The set of Frog Wake FV4s I ordered arrived today.   They arrived in a nicely printed cardboard box where the components are nicely packaged in a felted surface foam cutout.     Like the IIIPros, my initial impression is that the lever assemblies and calipers are nicely CNC machined.   (They look good, so they must perform great!) LOL

These FV4 calipers are about 95% the same mono-block machining as the IIIPro E4 calipers.  They have different piston sealing caps that will require a smaller tool to remove them when it comes time to rebuild. (No, not another tool!)
- The minor machining differences are related to how a few of the bolts screw into the housing, being either countersunk or not countersunk.
- The 4 pistons appear to be 16mm, and on these calipers do not appear to be ceramic, but they are cross slotted on the outside where the pads sit.  (Better heat resistance to absorbing heat from the pads?)
-  The FV4 calipers don't have the second bleed hole and bolt that the later IIIPro calipers had added to them.  (Therefore the same, to me, more difficult caliper bleeding process to get all of the air out.)

The Frog wake levers are completely different than the III Pros.   More similar to the Hope Tech or SRAM DB4s, where there is a removable top reservoir cover that has a reservoir/bladder cover on top of the reservoir.   
- Heck if I know if these levers will bleed and perform better than the IIIPro levers that I have come to dislike so much.
 
It will be a while before I get these on a bike, and now that there is snow on the ground, it might be until spring until I can really test them on good trails.  I might be able to test them on pavement, but time will tell.

Title: Re: Frog Wake FV4 MTB Brakes
Post by: Skepsist on December 01, 2025, 08:07:04 AM
Heyo very interested to hear if those brakes are any good.
Still running fine with the R2X4. Even bleeding them after cutting the hose was fine.
Currently thinking about building a bikepark bike based on the Fastwork DH Frame. Those FrogWake brakes look like a good idea for that.
They still use mineral oil right?
Title: Re: Frog Wake FV4 MTB Brakes
Post by: FredDias2018 on December 02, 2025, 06:54:56 AM
Heyo very interested to hear if those brakes are any good.
Still running fine with the R2X4. Even bleeding them after cutting the hose was fine.
Currently thinking about building a bikepark bike based on the Fastwork DH Frame. Those FrogWake brakes look like a good idea for that.
They still use mineral oil right?
yes, they use mineral oil. i like the lebycle oil, it's very cheap and has never failed me. also, i personally think DOT fluid is a faff. even brakes which supposedly take DOT can be ran on mineral oil if DOT fluid has never been used in them. for example, you can buy sram brakes that come bone dry from the factory, and just fill them with mineral oil and run them that way. never had issues.
Title: Re: Frog Wake FV4 MTB Brakes
Post by: Fat Larry on December 03, 2025, 06:41:38 AM
I know dot is a faf in bikes but its standard in cars and i haven't changed my cars brake fluid for years... what makes dot bike brakes so special that they need yearly fluid changes and the seals are supposed to give out after a few?
Title: Re: Frog Wake FV4 MTB Brakes
Post by: gribs on December 03, 2025, 07:10:44 AM
I know dot is a faf in bikes but its standard in cars and i haven't changed my cars brake fluid for years... what makes dot bike brakes so special that they need yearly fluid changes and the seals are supposed to give out after a few?

Absolutely nothing. My 13 year old Hopes have had one fluid change in that time and a mate has a set on a hard tail from the early 2000's that have only ever had pads. I suspect some of the hate for DOT fluid in mtb brakes comes from how bad Avid brakes were to live with. Micro leaking Shimano callipers seem far more common than any other brand for example but that's blamed on Shimano rather than the fluid they use.
Title: Re: Frog Wake FV4 MTB Brakes
Post by: Tijoe on December 03, 2025, 11:01:33 AM
I am not sure if I want to use my Frog Wake thread and dilute it by discussing other brake brands.  Perhaps I should start a new "Generic Brake" thread.

Thoughts?

I have in my possession 3 different sets of new brakes for braking experimentation.   The new Wheeltop 4-piston brakes, the set of Frog wake FV4s - both mineral based fluid,  and a set of Hope Tech Duo E4 brakes.  (Dual Right hand independent Levers with 2 calipers - Dot5.1 brake fluid based.)   

I have on order a bunch of Hope Tech 16mm Dot5.1 brake fluid caliper O-rings that should work on the IIIPro calipers, and other 16mm calipers, to convert them to being compatible with the Hope tech brakes.  (Frustrated because the shop I purchased from hasn't shipped them yet. - It's been a month already.)

A month + ago I purchased one of the Aliexpress dual rear caliper mounts.   (All the reviews complain that the second caliper quickly breaks off, so I added a 2mm thick steel brace to the bottom of mine to stiffen it up.)

My plan is to run the Hope Tech duo lever with one Hope E4 Caliper, and one IIIPro caliper, (And others)  and see how the Chinese caliper performs compared to the Hope Calipers.

Now that winter is here, this project will likely not get much testing until spring. I will work on the brakes and get things set up.

Title: Re: Frog Wake FV4 MTB Brakes
Post by: gribs on December 03, 2025, 04:23:15 PM
That's certainly going to be an interesting setup.
Title: Re: Frog Wake FV4 MTB Brakes
Post by: Tijoe on December 23, 2025, 05:51:40 PM
I installed the Front Frog wake FV4 on the bike.   I installed a slightly used 203mm rotor up on the front fork.   Rotor was cleaned, but not sanded.  1.80mm wide.  On the stand, the brake felt fine.  Good lever feel, and stops the free spinning wheel quickly.

I was able to get out and ride the bike for an 8 mile singletrack loop with about 700ft of climbing and descending.   
The front brake had terrible stopping power.   (I am hoping it is that the pads need bedding into the rotor.)

Today, I sanded the rotor and cleaned it.  I need to get some good weather to test ride the bike again.

Title: Re: Frog Wake FV4 MTB Brakes
Post by: Tijoe on June 27, 2026, 03:57:50 PM
Frog wake front brake update

I've put on about 1500 miles on my bike packing rig since installing the Frog Wake front brake.   Overall, this brake has functioned well.   EXCEPT...

On my most recent bike camping trip,  the NBWGL, there was a 10+ mile descent with numerous rough, difficult, 10+% grade forest service road descents where I had to start using my brakes almost continuously to keep my speed in check.  I was really hitting the rear Hope Tech E4 brake hard and heavy, and was starting to experience the beginning of brake fade, so I had to start using the front Frog Wake brake a lot more.   Over time, the Frog Wake heated up so much that the pistons expanded in the caliper and the pads were literally locking up onto the rotor.  I had to stop, and when I did, the front 203mm IIIPro rotor was locked to the caliper.  I definitely boiled the mineral oil.  I gradually dripped water on the caliper, let it sizzle and was able to cool it off.    At first the brake was mushy, but over time it started working OK again. 

For the other long steep descents during the 8 day ride, I tried to change my braking strategy to large quick bursts of braking,  rather than more brake dragging.

For reference,  typical forest service road descents on this bike are at speeds between 15mph and about 34mph. 25mph is my typical comfortable descent speed. On one asphalt descent, my top speed was about 36 mph.

For this trip, my rig weighed between 53 and 58 pounds, and I weighed around 190 lbs.

Regarding all of my brakes purchased from Aliexpress, they all seem to be missing some ingredient that makes them under-perform compared to the Hope Tech E4 I have installed on the back of this bike.
Title: Re: Frog Wake FV4 MTB Brakes
Post by: Fat Larry on July 02, 2026, 10:10:35 PM
I am not sure if I want to use my Frog Wake thread and dilute it by discussing other brake brands.  Perhaps I should start a new "Generic Brake" thread.

Thoughts?



I think a general brakes thread would be good.