Cube Agree GTC SL – review

Stable and good value for money

The Cube Agree GTC SL combines a competitively priced package of carbon chassis and a full complement of Shimano Ultegra components with a stable if undemanding performance that at £1899 represents good value for money. 

This is a bike that requires no immediate upgrades, and while the opportunity to improve performance with lighter wheels is one from which almost any machine will benefit, it is far from an immediate necessity here. Having tested the bike, we found the seating arrangement uncomfortable, despite the inclusion of a carbon seatpost, and would seek to make changes. Contact points are notoriously matters of personal preference, however, and this may only be a personal view.

The Cube Agree GTC SL offers excellent value for money and a ride that is stable but not sluggish

The Agree GTC SL offers a predictable, rather than incendiary ride; the sort of quietly impressive performance one might expect from a  bike we weighed at 7.87kg and which is dressed in Shimano’s second-from-top mechanical groupset. It performed all aspects of the ride without complaint: cornering with confidence, cantering along flat roads, and proving a willing accomplice on climbs. It remained stable on descents, too, and responded eagerly to out-of-the-saddle efforts on flat roads.

The chassis

The carbon frameset and carbon-bladed fork offered a degree of comfort absent from some harsher composite frames of our acquaintance, and allowed us to cover the miles in relative comfort. The proportions of the Agree GTC SL’s semi-compact geometry suited us well, and delivered a well-mannered ride from which nasty surprises were pleasingly absent, and where many of the implicit promises of the geometry chart were fulfilled.

The top-tube of the Agree GTC SL was shorter than some on more race-oriented bikes we’ve tested and created a less demanding riding position

All of the design features by which a contemporary carbon frame can be instantly recognised were present and correct and performed as advertised. The bulky, if not gigantic bottom bracket shell delivered sufficient stiffness under load, notably on climbs where the very short 406mm chainstays played their part in effectively converting our efforts to forward motion. The other pieces in the ‘stiffness’ jigsaw – an oversized headtube offering sufficient real estate for a union with a similarly oversized downtube – also made their presence known in a ride that was taut but not jarring.

The components

We’re far from alone in our admiration of Shimano’s long-established Ultegra offering, and this latest incarnation, the 6800, raises the standards set by its forebears. The compact chainset with its 50-34 chainrings proved easy to turn even on double digit gradients and will offer much in the way of support to the newcomer – perhaps the Agree GTC SL’s intended audience – when the road points skywards.

A full deployment of Shimano’s Ultegra 6800 groupset makes the Cube Agree GTC SL excellent value at £1,899

The hoods of the 6800 levers felt slim and comfortable in the hands, as did the sculpted lever. The four-arm chainset follows the aesthetic standard established by its Dura-Ace senior sibling and as such is a thing of beauty. It proved suitably stiff, too. Finally, the dual pivot brakes delivered more than adequate stopping power on the almost universally wet roads that characterised our test period. In short, Ultegra provides a standard of performance likely to exceed the needs of most ordinary riders (this correspondent included) and its full deployment on a bike of this value is to be welcomed.

The wheels – aluminium clinchers made by DT Swiss for Cube (“Cube Wheel System”) – are perhaps more accurately described as  functional than outstanding. The tyres are badged as Schwalbe One, but are also special editions made for Cube and lacked the softness and suppleness we’ve come to expect from the after-market incarnation.

The swept-back tops of the Syntace handlebars offered no advantage that we could find, unless you’re seeking a bar on which it’s easy to bang your knees. That said, they’re an improvement on the multi-profiled offerings from Easton that have featured on previously-tested bikes from Cube. The two-tone handlebar tape we felt was a nice finishing touch.

The ride

Riders seeking a machine that offers stability without feeling sluggish will find much to like in the Cube Agree GTC SL. It failed to ignite the road in the manner of more race-oriented (and expensive) machinery through the gates of RCUK Towers (the recently-tested Lapierre Xelius EFI 600, for example) but it offered dependable companionship and a ‘we’ll see this through together’ persona absent from flightier steeds.

We’d suggest that by imbuing a bike of this price with such characteristics, Cube have got it right. Most (by no means all) experienced riders will seek a machine that challenges them a little, and by the time you’ve reached such a position, you’ll perhaps be ready to invest a greater sum than that required to own the Agree GTC SL. Those who have passed the ‘toe in the water’ stage, but have yet to take the final plunge, in sporting and financial terms, are perhaps those the German brand had in mind when sketching out this well-equipped but undemanding machine.

We didn’t find the seating arrangements, comprised of Cube’s carbon Syntace P6 Hi flex post and Selle Italia X1 road saddle comfortable, but this may only be a personal response

Our acquaintance has been formed solely beneath the grey skies of winter and on the unforgiving road conditions routinely delivered by the season. The Agree GTC SL’s patient approach suited the business of building base miles well: a characteristic that we suspect will transfer easily to the summer season when the long miles of the endurance event replace those of winter training. The pot hole-ravaged and debris-strewn highways of winter provided an adequate test of its ability to take the rough with the smooth, and we’re pleased to say the Agree GTC SL passed with flying colours. The seating arrangements, comprised of Cube’s carbon Syntace P6 Hi flex seatpost and Selle Italia X1 road saddle, didn’t suit us, but this may only be a personal response, however.

We tucked behind the handlebars on the steepest descents of our local loops early in our acquaintance and found our confidence rewarded with stability even at high speeds. It was reliable in corners too, despite the routinely wet surfaces we encountered. Our most enjoyable moments in the Agree GTC SL’s company, however, occurred on flat, straight roads, where we shifted down the block, pressed harder on the pedals and discovered a willingness belied by its unassuming response to less intense effort.


The Cube Agree GTC SL is a well-spec-ed, good value package likely to suit riders with a growing love for cycling and ready to take their next step on a ladder begun with an entry-level bike. The full Shimano Ultegra groupset doesn’t look out of place on machines costing significantly more, and with an inevitable – though not immediately necessary – wheel upgrade, you’d have a machine able to tackle any duty with confidence.

The changes we’d make from the box would be minor: saddle and seatpost, a conventionally-shaped handlebar, and tyres. We’d also advise riders seeking a lively and engaging ride to continue their search. If sure-footed stability combined with eagerness when demanded are more in your line, the Cube Agree GTC SL might be for you.

Discuss in the forum

Price: £1899
Size: 50, 53, 56, 58, 60, 62
Colour: carbon and white

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