The recent trend of brands developing cross-country bikes with attitude is a welcome one and the new 2021 Transition Spur is the latest.
The bike has 120mm of travel front and back, a RockShox SID fork and XC-friendly kit, a dropper post and sees a 66-degree head tube angle, 50mm stem and long reach figures.
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Over the past few weeks and months, we've seen a host of aggro XC rigs released. First was Cannondale's new Scalpel SE with more aggressive geometry and longer travel than the standard model, then came Specialized's Epic EVO, a hard(er) core version of its flyweight XC race rig.
Five things you need to know about the 2021 Transition Spur
- It has 120mm of rear wheel travel that can be adjusted to 100mm by changing the shock stroke
- It's available in three build kits and a frameset and ranges in price from £2,999.95 to £8,999.95
- With a 66-degree head tube angle, long reach and wheelbase figures it should be more versatile than its suspension figures suggest
- It uses a flex stay instead of a pivot with a bearing between the seat and chainstays
- The front and rear triangles and rocker link are made from Toray carbon fibre
Most recently, Yeti launched its 'lunchtime ride' bike, the SB115, which can be considered as a souped-up version of its SB100 cross-country race bike.
So where does the new 2021 Transition Spur fit in this jigsaw puzzle of XC, trail and all-mountain bikes converging in short travel packages?
2021 Transition Spur frame details
Built from all-carbon front and rear triangles, with a carefully curated blend of different types of Toray carbon fibre, Transition hopes it's created the perfect balance of frame stiffness, strength and impact resistance.
The brand's confidence in its manufacturing processes is backed up with a lifetime warranty for the bike's original owner and a crash replacement scheme should the worst happen.
Transition claims the 2021 Spur's frame and shock (SIDLuxe) weighs 2.45kg for the medium, while the full SRAM XX1 Eagle AXS bike weighs a claimed 11.2kg – also for the medium frame size.
The down tube and bottom bracket area has integrated frame protection to help ward off potentially ruinous rock strikes, while the chainstay also has built-in chainslap protection to help keep the bike quiet when things get bumpy.
Along with two sets of bottle cage mounts – one on the top of the down tube and one on the underside of the down tube – there's also an accessory mount under the top tube.
Although the mount uses the same spacing standard as a bottle cage, there could be clearance issues with the rear shock and linkage if you wanted to mount a third bottle to the bike.
Thanks to a straight seat tube, it's possible to insert seatposts deep into the frame. This means prospective owners could upsize dropper travel.
Transition is so confident with its dropper post insertion depths that it offers OneUp's V2 Dropper Post with 210mm of travel on the GX-build full bike.
There are guide tubes for the internal cable routing, so there should be no more fishing around for gear cables.
The icing on the cake is the Spur's threaded 73mm bottom-bracket (BB) shell, which, it claims, eliminates noises associated with press-fit BB options.
2021 Transition Spur suspension details
Built around 120mm of travel using Transition's GiddyUp suspension system, it has a 30 per cent progression rate with a linear rate of change.
This means, Transition claims, the bike should be able to offer great small bump sensitivity, support and, thanks to the anti-squat tune, levels of pedalling performance riders expect on a 120mm travel bike.
Instead of having a pivot joining the chainstays and seatstays together, like its other bikes, Transition's opted to use a flex stay system, where the seatstay flexes enough to allow the suspension to activate. Transition claims this reduces complexity, saves weight and improves reliability.
The frame does still have some pivots, though. The EnduroMAX bearings used are designed specifically for suspension pivots and have added weather protection. They're also said to be available worldwide should you need to replace them.
In its stock setting, using a 190mm x 45mm rear shock, the Spur has 120mm of travel, it is possible to decrease travel to 100mm for an even more spritely feel. This is done by reducing shock stroke to 37.5mm, but the eye-to-eye length remains unchanged.
2021 Transition Spur geometry details
| Frame size | Small | Medium | Large | Extra-large |
|---|---|---|---|---|
| Reach (mm) | 425 | 455 | 480 | 510 |
| Stack (mm) | 600 | 610 | 619 | 632 |
| Effective top tube length (mm) | 569 | 602 | 630 | 664 |
| Seat tube length (mm) | 380 | 410 | 460 | 500 |
| Effective seat tube angle (degrees) | 76.7 | 76.2 | 75.9 | 75.6 |
| Saddle height for ESTA (mm) | 600 | 660 | 720 | 780 |
| Head tube length (mm) | 100 | 110 | 120 | 135 |
| Head tube angle (degrees) | 66 | 66 | 66 | 66 |
| Chainstay length (mm) | 435 | 435 | 435 | 435 |
| Wheelbase (mm) | 1156 | 1190 | 1219 | 1255 |
With Transition's Speed Balanced Geometry (SBG) at its heart, the Canadian brand claims the bike manages to strike the perfect balance between low-speed agility, front wheel traction and rider weight all while providing confidence on steep and fast sections of trail.
This has been achieved by combining a slack head-tube angle with shorter offset forks – a 44mm offset is specced to the bike as standard – to reduce front-end length whilseincreasing trail and slowing the bike's steering down, making it more stable.
For a 120mm travel XC bike, the 66-degree head angle is a standout figure.
Combined with lengthy reach figures (the large sits at 480mm), long wheelbases across the sizes and relatively large chainstays, it's clear to the see the geometry should outgun the headline travel figures.
2021 Transition Spur models and pricing
The 2021 Spur is available in three builds and a frameset with prices ranging from £4,999.95 / $4,999 for the SRAM GX Eagle full build bike up to £8,999.95 / $8,999 for the SRAM XX1 Eagle AXS full bike.
The frameset, with RockShox SID Luxe Ultimate shock, retails for £2,999.95 / $2,999.
2021 Transition Spur GX Eagle
- Frame: Spur Carbon 120mm travel
- Shock: RockShox SIDLuxe Select+
- Fork: RockShox SID Select+ 120mm travel, 44mm offset
- Groupset: SRAM GX Eagle (10-52t) with Stylo 7K cranks
- Brakes: SRAM G2 RS
- Bar/stem: ANVL Mandrel Alloy 800mm wide, 20mm rise / Race Face Aeffect R 50mm long
- Seatpost: OneUp V2 dropper post
- Wheels: Stans Arch S1 Team
- Tyres: Maxxis Dissector 3C EXO 2.4 x 29in (f), Maxxis Rekon 3C EXO 29 x 2.4in (r)
- Price: £4,999.95 / $4,999
2021 Transition Spur X01 Eagle
- Frame: Spur Carbon 120mm travel
- Shock: RockShox SIDLuxe Ultimate
- Fork: RockShox SID Ultimate 120mm travel, 44mm offset
- Groupset: SRAM X01 Eagle (10-52t) with SRAM X1 carbon cranks
- Brakes: SRAM G2 RSC
- Bar/stem: OneUp Carbon Bar 800mm wide, 20mm rise / Race Face Turbine R 50mm long
- Seatpost: OneUp V2 dropper post
- Wheels: DT Swiss XR 1700 Spline 25
- Tyres: Maxxis Dissector 3C EXO 2.4 x 29in (f), Maxxis Rekon 3C EXO 29 x 2.4in (r)
- Price: £5,999.95 / $5,999
2021 Transition Spur XX1 Eagle AXS
- Frame: Spur Carbon 120mm travel
- Shock: RockShox SIDLuxe Ultimate
- Fork: RockShox SID Ultimate 120mm travel, 44mm offset
- Groupset: SRAM XX1 Eagle AXS (10-52t) with SRAM XX1 carbon cranks
- Brakes: SRAM G2 Ultimate
- Bar/stem: OneUp Carbon Bar 800mm wide, 20mm rise / Race Face Turbine R 50mm long
- Seatpost: RockShox Reverb AXS
- Wheels: DT Swiss XRC 1200 Spline 25 Carbon
- Tyres: Maxxis Dissector 3C EXO 2.4 x 29in (f), Maxxis Rekon 3C EXO 29 x 2.4in (r)
- Price: £8,999.95 / $8,999
