A fundamental geometry problem blunts the Jamis Faultline A1's performance compared to the best in class, but it's still a capable bike that's fun to ride.

Product Overview

Overall rating:

Score 6

Jamis Faultline A1

Pros:

  • Impressive specification

Cons:

  • Seat tube is way too slack

Product:

Jamis Faultline A1 review

Manufacturer:

Price as reviewed:

£1,950.00
TAGS:

The Jamis Dakar has always been a strong contender in our entry-level, budget full-suspension bike test. But with the category shifting to embrace the improved rollover and stability that bigger 29in wheels bring to trail riding, it had to step aside and make way for the new Faultline A1.

Need to know:

  • Sag gradients on the RockShox Deluxe shock make suspension set-up easy
  • Available in four frame sizes, S to XL all with very slack seat tube angles
  • Light wheels and 120mm travel make the Faultline more XC focused
  • No chainstay protection and rattly cables make for a percussive ride

Boasting 120mm of suspension at the rear, the Faultline A1 29 doesn’t quite live up to its freeride sounding name as the travel puts it more at the XC end of the trail bike continuum.

The sleek, alloy frame has a lot in common with its smaller wheeled sibling, where both use Jamis’s signature MP2 suspension, a single pivot design that places the shock directly under the top tube. Internal cable routing gives the Faultline frame a smooth clean appearance, but even when we were assembling the bike we noticed that the cables rattled inside the down tube. So while you can’t see them, they’ll make themselves known to you and everyone you’re riding with. Captured cable entry and exit ports are needed to keep the cables tight, or, at the very least, foam cable covers to reduce the rattle. A rubber chainstay protector wouldn’t go amiss either, as it would reduce some of the chain noise and protect the paint on the chainstay too.

Hydroformed tube profiles give the Faultline frame an organic feel, but Jamis seems to have taken a firehose approach to the seat tube, with its rather dramatic kink. And it doesn’t just look dramatic, it dramatically impacts the riding position and handling of the bike. With a seat tube angle that’s slacker than the head angle, the saddle is really far behind the bottom bracket. It also skews the top tube measurement; the size L Faultline measuring 670mm. That’s a whopping 50mm longer than the Vitus or Polygon, even though the Jamis has a much shorter reach measurement.

In fact, it’s such an outlier in that regard, we can only assume that someone messed up on the original design and the mistake made it all of the way into production.

Suspension

In keeping with the more XC oriented ride, the rear suspension on the Faultline has been configured to provide extra support around the sag position to keep pedalling efficiency high.

The RockShox Deluxe Select+ RL shock also has a lot of compression damping, even on the open setting. So much so that we ran the rebound damping fully open to try to compensate, but even then it still didn’t ping back to the sag position as quickly as we’d have liked and that’s with an 80kg rider so any lighter and you’ll struggle then to get a half-decent suspension set up.

Combine the heavy-handed approach to compression damping and the linkage configuration and the trade off for the improved pedalling performance is that the rear suspension on the Jamis isn’t as sensitive and provides less traction than the Vitus Mythique. Get past the sag point, and the Jamis is also too eager to use all of its travel too quickly. Which is far from ideal when we measured the travel and it’s already 11mm shy of the claimed 120mm.

Up front, the RockShox 35 Gold RL fork gets 130mm travel and shares the same degree of adjustability as the rear shock. The difference being it has a usable range of adjustment, where the 35mm chassis makes the front end of the bike feel pretty stout and improves steering precision.

We ran the fork pressure quite a bit higher than the recommended settings hidden on the back of the fork lowers though, just to help prop the front end up and maintain more stable geometry. Thankfully our workaround didn’t seem to impact the fork’s ability to track terrain, even if it limits overall travel to about 110mm.

Components

Where the Jamis Faultline A1 really appears to deliver, is in the drivetrain. The Race Face Ride chainset gives the bike a custom feel and with a 32t chainring and longer 175mm crank arms the Jamis is clearly designed to motor along at speed. Factor in the Shimano SLX 12-speed derailleur, shifter and Micro Spline rear hub with a wide-range 10-51t cassette and you’d expect solid dependable shifting, even under load.

Unfortunately, that’s not the case, because Jamis has made the same mistake as Polygon; fitting a cheaper 12s KMC chain rather than sticking with Shimano.

The Faultline’s focus on speed is emphasised further by the Fast Compound and lighter casing WTB Vigilante/Trail Boss tyre comb. In fact, the narrower rims, lighter tyres and top-end transmission, definitely help the Jamis on the scales, and at 15.07kg it’s easily the lightest bike in test.

Another nod to weight saving is the smaller 160mm rear brake rotor, but sadly you pay the price in reduced stopping power. And while the longer four-finger Shimano brake levers look goofy, set them up well inboard of the gips and you can take full advantage of the increased leverage to increase stopping power.

They are ultra-reliable too, so if you are a fairweather rider, you’ll just have to dust off the bike, inflate the tyres and you’ll be ready to go next spring.

Performance

On flatter, rolling terrain the ultra-rearward seated piston on the Jamis Faultline A1 is just about bearable. Hit the hills, however, and your weight is just too far behind the BB to make for an efficient climbing position. This also makes it impossible to set up the suspension correctly. Get it right for seated climbing and it’s too firm when out of the saddle and vice versa.

The bike also feels much more flimsy and flexy compared to the Polygon Siskiu T8 or Vitus Mythique. The narrow rims probably play a big part here, but overall the tubing profiles and pivot hardware don’t look as stout either.

Given its shortcomings the Faultline can still be ridden pretty hard. The linear rear suspension, while not the most supple, still takes the edge of the bigger hits really effectively and when the WTB Vigilante front tyre finds soft ground that it can sink its teeth into, you can rip turns and still have a total blast on the Jamis.

This category has moved on a lot in the past couple of years however, and faced with stiff competition from the likes of Vitus and Polygon, Jamis really needs to up its game if it wants to be competitive at the £2k price point as there’s really no room for error.

Verdict

We’d love to say the Jamie Faultline A1 was without fault, but even from the very first ride it was clear that wasn’t the case. With the saddle pushed all of the way forward on the head of the seat post, we still felt too far behind the BB for comfortable pedalling. Start winching up a climb and things get even worse. Why Jamis didn’t simply make a 29er version of the popular Dakar is anyone’s guess, but if it wants to have a 29er full suspension bike that can compete with the likes of Polygon and Vitus, it will need to go back to the drawing board and straighten out some of the kinks in the Faultline A1 design.

Details

Frame :6061 T6 aluminium, 120mm travel (109mm measured)
Shock :RockShox Deluxe Select+ RL
Fork :RockShox 35 Gold RL 51mm offset, 130mm travel
Wheels :Shimano SLX 110/148mm hubs, Stan's No Tubes Arch D 29 rims, WTB Vigilante/Trail Boss 29x2.35/2.25in tyres
Drivetrain :Race Face Ride 32t, 175mm chainset, Shimano SLX derailleur and 12-sp shifter, Shimano SLX M7100, 10-51t cassette
Brakes :Shimano MT401, 2-piston 180/160mm rotors
Components :Race Face Ride 760mm bar, Race Face Ride 50mm stem, KS Rage 150mm post, WTB Volt saddle
Sizes :S, M, L, XL
Weight :15.07kg (33.22lb)
Contact :gooutdoors.co.uk
Size tested :L
Head angle :66.9º
Seat angle :64.1º
Effetive Seat angle :70.2º
BB height :332mm
Chainstay :445mm
Front centre :760mm
Wheelbase :1,205mm
Down tube :725mm
Seat tube :490mm
Top tube :670mm
Reach :453mm