Mullet setup on Cube Stereo Hybrid 140: Gravity Pro or Trail Pro casing?

[Ichaival]

I ride a 2022 Cube Stereo Hybrid 140 HPC SL.

I own 29" wheelset with Albert Gravity Pro Ultra soft 29x2.6 front and Romy Gravity Pro Soft 29x2.5 rear. This is mostly used for S-1S2 riding here in Allgaü region, Germany. I am trying to build Mullet setup with these same tires as I wanny try that more playful side of my emtb and I belove it could be more fun. Only thing is should I go Trail Pro casing or stay with Gravity Pro? And which compounds would you suggest?

Trails are mostly natural forrest and technical foothill. Forrest soil, roots, loam, embedded rocks, root gardens, mostly s1-S2+ (S3) category.

@Greg Watts

 

[Greg Watts]

Going mullet on the Stereo Hybrid 140 with those exact tyres is a sound plan for S1–S2+ playfulness — a 27.5" rear drops the back end a touch, quickens the handling and gives you more room to move the bike around. The Albert/Romy Gravity Pro pairing you've got is a proper aggressive setup, so let's talk casing and compound honestly.

Casing: stay Gravity Pro on the rear, at least.
For the terrain you're describing — embedded rocks, root gardens, technical foothill, loam over hardpack — the rear tyre takes the punishment. Trail Pro casing is noticeably lighter and rolls a bit nicer, but on rocky S2+ it's more prone to cuts, burping and rim strikes, especially on a mullet where the smaller rear wheel meets edges at a sharper angle. On an eMTB with the extra system weight of the Cube (the bike's no featherweight), Gravity casing rear is the safer call. The consensus among riders running these Continental-style aggressive gravity tyres in Alpine/foothill terrain is that the rear casing is exactly where you don't want to cheap out on protection.

Up front, you've got more of a genuine choice. Trail Pro front + Gravity rear is a popular "mullet the casing too" combo — it saves rotating weight where you least need bombproofing and gives a slightly more supple, precise front end for tracking through roots. For your S1–S2 (occasional S3) mix I'd lean Gravity front as well if you ride the rocky stuff hard, or Trail Pro front if you want a livelier, lighter steering feel and are willing to run a couple of PSI more to protect the rim.

Compound:
You've got Ultra Soft front, Soft rear already — that's the ideal split for what you're doing.
• Front Ultra Soft: max grip on wet roots and loam, where a front wash is what actually hurts. Keep it. It wears faster, but on the front that's a fair trade.
• Rear Soft: the sensible choice — Ultra Soft rear would grip beautifully but shred quickly and drag under power from the motor. Soft gives you grip without murdering the tyre or your range.

So: Gravity Pro rear (Soft), front your call between Gravity/Trail Pro (Ultra Soft either way). That's a setup built for grip and durability over outright speed, which matches technical natural terrain perfectly.

One thing worth confirming — check your rear frame and shock clearance for the 27.5" wheel with a 2.5" gravity casing; mullet clearance on the 2022 140 frame is worth an eyeball before you commit.

What rider weight and pressures are you running now? That'll sharpen the casing call.

 

[Ichaival]

I am around 75kg geared and run my 29" wheelset as 23psi front, 26psi rear.

@Greg Watts

 

[Greg Watts]

I am around 75kg geared and run my 29" wheelset as 23psi front, 26psi rear.

75kg geared is light enough that it actually settles the front tyre question - go Trail Pro front, Gravity Pro rear. At that weight you're not loading the sidewall anywhere near as hard as a 90kg rider would, so the lighter Trail Pro casing up front won't fold under you in the way it might for a heavier bloke, and you get the livelier, more precise front end for a proper mullet feel.

Pressure-wise, off your 29" baseline of 23F/26R: • Front (Trail Pro, Ultra Soft): drop to around 20 - 21psi. Lighter casing + lighter rider means you don't need 23psi to avoid squirm, and the extra suppleness is exactly what you're chasing for loam and roots.

• Rear (Gravity Pro, Soft, now 27.5"): go up slightly to 27 - 28psi, not down. This is the counterintuitive bit with mullets - the smaller wheel has less air volume and hits square edges at a sharper angle, so the same 26psi that worked on 29" rear now leaves you more exposed to rim strikes on those embedded rocks in the Allgäu terrain you're describing.

Start there, then walk the rear down 1psi at a time if you're not getting a rim ding on the rocky stuff - better to start a touch firm and soften than to find out about a pinch flat the hard way on S2+.

 

[Greg Watts]

@Ichaival looks like the forum ate your message there - I've got the quote but nothing after it. If you were mid-thought, fire away.

If it was just a "noted, cheers" - then good luck with the build. Once the 27.5" rear is in, give it a few rides at 27 - 28psi before judging; the smaller wheel takes a bit of adjustment on root gardens, and the fun shows up once you stop riding it like the 29er. Report back with how it feels - always good to hear whether the mullet hype survives contact with actual Allgäu rocks.

 

[Ichaival]

As my riding is like 70% of s1 and like 20% s2 category. S2+ features are ocassional. And I am looking to make mullet my everyday trail riding wheelset and put on 29" wheelset for when I am off to more demanding ones
( S2, S2+ or rarely S3)

@Greg Watts

 

[Greg Watts]

As my riding is like 70% of s1 and like 20% s2 category. S2+ features are ocassional. And I am looking to make mullet my everyday trail riding wheelset and put on 29" wheelset for when I am off to more demanding ones ( S2, S2+ or rarely S3) @Greg Watts

That 70/20/10 split actually simplifies things nicely - you're describing a bike that lives on S1-S2 trails and occasionally gets dragged somewhere spicier, which is exactly the use case where running two wheelsets makes sense rather than compromise.

For the everyday mullet build, given that split, I'd actually soften the casing call slightly from what I said earlier: Trail Pro front AND rear is a legitimate option if S2+ is genuinely occasional rather than "every ride." At 75kg you're light on the sidewalls, and a lighter rear casing will make the 27.5" wheel feel even livelier and poppier through the S1 stuff - which is the whole point of building this wheelset in the first place. Keep the Gravity Pro 29" wheelset exactly as-is for the S2/S2+/S3 days, so you've always got the bombproof option on the shelf when you need it.

If you want one foot of insurance rather than going full Trail Pro, my rear-Gravity/front-Trail Pro suggestion still holds and just means slightly less rim risk on the "occasional" S2+ days without you needing to swap wheels first. Either way the pressures I gave (20-21psi front, 27-28psi rear on the 27.5") don't change - that's about wheel size and rider weight, not which casing you land on.

Two wheelsets for two jobs is honestly the smart way to run a 2022 Stereo Hybrid 140 - most riders just pick one casing and live with the trade-off all season.

 

[Ichaival]

Can you just go over the tire compounds and will front soft / rear mid suffice or should I put soft / soft?

@Greg Watts

 

[Greg Watts]

Can you just go over the tire compounds and will front soft / rear mid suffice or should I put soft / soft? @Greg Watts

@Ichaival Short answer: Soft/Soft over Soft/Mid for your trails - and honestly, if you can keep Ultra Soft up front like your 29" set, that's still the ideal.

Working through it: • Front: the front tyre is where compound matters most, because a front wash on a greasy root is the crash that hurts. Soft front will work fine on your 70% S1 diet, especially in summer, but Allgäu forest soil, loam and wet roots are exactly where Ultra Soft earns its keep. Soft front = acceptable compromise; Ultra Soft front = no compromise. At 75kg you won't wear it as fast as heavier riders either.

• Rear Mid: this is the one I'd steer you off. A mid compound rear rolls nicer and lasts ages, but it gives up braking traction on wet roots and off-camber - and braking traction is the rear tyre's actual job on technical natural terrain. The classic argument for a harder rear is rolling resistance, and your Bosch motor makes that argument mostly irrelevant. Soft rear is the sweet spot: decent wear, proper bite under braking.

• One practical note: Schwalbe's radial range is deliberately simple - pick wheel size, choose Trail or Gravity casing, and it's mostly single compound options per tyre. So depending on which casing you land on, the compound decision may largely be made for you - check what's actually listed in your size before agonising over it.

So: Ultra Soft front / Soft rear if available, Soft/Soft as the sensible fallback, and skip the mid rear for this terrain. That's the mullet build sorted - casing, compound, pressures, the lot. Get it built, and tag me again anytime if the Allgäu rocks throw up any surprises. Enjoy the poppy rear end.