It’s easy to assume the big, fat tyres of plus bikes dominate their ride character to the point where they all feel the same. But the more we ride the more it’s clear you can end up with very different bikes even with the same balloons wrapping the wheels.
It’s also clear that not all manufacturers have got their handling or clearances sorted to make the best of the bigger volume rubber. The good news is the Tarn is the one of the best plus hardtails we’ve ridden, and it has a great parts package for the price too.
That second bit is particularly impressive, given the tapered head tube, super-sloped top tube, Boost 148x12mm rear axle frame, built from Genesis’s own double-butted Mjolnir steel tubing blend. The wide-spread rear stays provide a smoothly supple ride that really syncs well with the kind of experience you’re likely to want from a plus bike. Rather than feeling dead under power like some steel frames it’s got a really lively spring as you press on the Race Face cranks.
‘Boost’ 148x12mm rear axle spacing features out back
Despite being much heavier, the Maxxis Chronicle tyres roll really fast and, remarkably, the complete bike is lighter than both the other steel bikes we were riding alongside the Genesis (namely the Onza Jackpot and Ragley Piglet).
We rarely ran out of braking and driving grip even on the sketchiest scree sections of the surrounding wild bridleways either. Add the root- and rock-ignorant, momentum-maintaining tyre volume and the Tarn repeatedly dropped the Ragley and Onza on the rougher singletrack sections.
This has actually become more significant the more we’ve ridden other plus bikes too. That’s because several of those have proved to either under- or over-steer frustratingly or just have an awkward overall balance that’s left us dabbing and cursing.
The Tarn’s personality is lively and playful – what you want from a plus bike
In contrast, the Tarn’s combination of super long stretch and 68-degree head angle made the fat front tyre feel confident yet easily responsive at all speeds. It even feels okay on the sloppy, slippery conditions that are a nightmare on most plus bikes.
The 110mm wide Boost axle of the Reba fork is further stiffened with oversized hub contact caps for rich front end feedback and the under-seat dropper lever means it’s definitely not scared of the steeps.
It’s always the sign of a good bike when we’re scratching around for something to offset all the positives with. However, the only things we didn’t like on the Tarn were the racer-style foam grips, which neither feel good nor last long. That makes them the polar opposite of the rest of this surprisingly playful, well-sorted plus-sized package.
|Available Sizes||S M L XL|
|Brake Levers||Shimano BL-M506|
|Seatpost||KS Dropzone manual dropper 31.6mm|
|Shifters||Shimano Deore XT SL-M8000 (R/H only)|
|Stem||Genesis Trail, 55mm|
|Spoke Type||14G Stainless Silver DB w/ Brass Nipples|
|Rear Wheel Weight||3110|
|Bottom Bracket Height (in)||12.2|
|Seat Tube (in)||19.02|
|Standover Height (in)||28.54|
|Top Tube (in)||25.59|
|Rims||WTB Scraper i45 27.5" Sleeved|
|Rear Tyre||Maxxis Chronicle 27.5x3.0", EXO/TR, 120TPI Folding|
|Bottom Bracket||Raceface X-Type Team XC, 73mm|
|Front Hub||KT Sealed Cartridge 6-Bolt|
|Brakes||Shimano BR-M447 w/ SM-RT56 180/160mm Rotors|
|Cassette||Shimano CS-M8000, 11-42T|
|Cranks||Race Face Aeffect Cinch 30T|
|Fork||RockShox Reba RL Solo Air 120mm|
|Frame Material||Genesis Mjölnir Seamless Double-Butted Cromoly|
|Front Tyre||Maxxis Chronicle 27.5x3.0", EXO/TR, 120TPI Folding|
|Rear Hub||KT Sealed Cartridge 6-Bolt|
|Front Wheel Weight||2470|
|Grips/Tape||Genesis Silicon, 130mm|
|Handlebar||Genesis Flattop, 740mm|
|Rear Derailleur||Shimano Deore XT RD-M8000-GS|
|Frame size tested||L|