Mantra Stiffness advice

[Chino]

Here’s the fully adjusted version including your use case:

Hi everyone,

I’m an AIDA 4 freediver from Germany, mainly diving in cold German lakes, and I’m planning on doing a competition depth safety course in May. My use case: my own constant weight bifins dives (up to ~45m), transfers, safety for buddies, and during the safety course—and if I succeed, maybe for 2–3 competitions per YEar in German lakes.

I currently use the C4 MB-001 in stiffness 25+, and I’m generally happy with it, but I have some issues:

1. The C4 footpockets are incredibly comfortable, but they offer little lateral stability. Combined with my unstable joints, this leads to blade twisting on my back kick.

2. After long days, I think a slightly softer blade could be right.

I have CETMA’s S-Wing footpockets at home, so I’m thinking about a CETMA blade, and the Mantra seems right. Now: which stiffness?

1. I’m 85 kg (±4 kg over the season).

2. CETMA’s chart: Soft up to 85 kg, Medium above 85 kg.

3. I found mixed arguments online, which confuses me.

4. I asked a top athlete (96 kg) who says he leans more toward soft-medium to medium, which confuses me even more since CETMA only offers Extra Soft, Soft, and Medium.

So, can anyone advice me here? Maybe someone knows the comparison between Mantra and the C4?

thanks!

 

[vladimir fedotov]

Here’s the fully adjusted version including your use case:

Hi everyone,

I’m an AIDA 4 freediver from Germany, mainly diving in cold German lakes, and I’m planning on doing a competition depth safety course in May. My use case: my own constant weight bifins dives (up to ~45m), transfers, safety for buddies, and during the safety course—and if I succeed, maybe for 2–3 competitions per YEar in German lakes.

I currently use the C4 MB-001 in stiffness 25+, and I’m generally happy with it, but I have some issues:

1. The C4 footpockets are incredibly comfortable, but they offer little lateral stability. Combined with my unstable joints, this leads to blade twisting on my back kick.

2. After long days, I think a slightly softer blade could be right.

I have CETMA’s S-Wing footpockets at home, so I’m thinking about a CETMA blade, and the Mantra seems right. Now: which stiffness?

1. I’m 85 kg (±4 kg over the season).

2. CETMA’s chart: Soft up to 85 kg, Medium above 85 kg.

3. I found mixed arguments online, which confuses me.

4. I asked a top athlete (96 kg) who says he leans more toward soft-medium to medium, which confuses me even more since CETMA only offers Extra Soft, Soft, and Medium.

So, can anyone advice me here? Maybe someone knows the comparison between Mantra and the C4?

thanks!

Hi! With a similar weight and height of 187 cm, I wanted to order medium-soft blades when buying new Alchemy-V3-30, but the manufacturer recommended medium stiffness when placing my order. At first, I felt like they required slightly more effort, but the paddling efficiency increased. Having gotten used to it, I no longer notice this extra effort, but I continue to see improved paddling efficiency and control.
It's also important to remember that the angle of the blade is important when deep diving. My fins has 30* and I like it.
My advice: ask the manufacturer for their opinion.

 

[Chino]

Hi! With a similar weight and height of 187 cm, I wanted to order medium-soft blades when buying new Alchemy-V3-30, but the manufacturer recommended medium stiffness when placing my order. At first, I felt like they required slightly more effort, but the paddling efficiency increased. Having gotten used to it, I no longer notice this extra effort, but I continue to see improved paddling efficiency and control.
It's also important to remember that the angle of the blade is important when deep diving. My fins has 30* and I like it.
My advice: ask the manufacturer for their opinion.

Thanks dude. Cetma recommended Medium. Gonna buy it

 

[david85burger]

Given your weight and current use of C4 25+ blades, the CETMA Mantra in Soft is likely closer to what you want—offering more comfort and reducing fatigue while still giving enough power for 45 m dives and safety work. CETMA’s chart puts you right at the cutoff, but many divers your size prefer Soft over Medium for long sessions, especially if joint stability is an issue. Medium would feel stiffer than your current setup, while Soft should feel slightly easier and more forgiving HCTRA