The Jamis Xenith Pro Di2 is one of the new crop of bikes using Shimano's Ultegra Di2 group to bring electronic shifting to the masses (or at least, down to a more affordable price point). At £2400, the Jamis is among the cheapest carbon-framed Ui2 bikes out there, but it's more than just a groupset, it's also a pretty decent bike in its own right.
The frame comes out of the same mould as the top level Xenith SL, employed by the UCI continental Jamis/Sutter Home squad in the US, only with lower grade fibers so you'd expect it to be racy. Up front, a tapered fork keeps everything pointing in the same direction while the downtube and stays combine to form a solid power transferring platform.
The bottom bracket is a suitably large Pressfit 30 number though an adaptor is used for the Shimano Ultegra cranks so you don't get the full stiffness benefit there. For a more in depth look at the frame and componentry, go check out what we had to say when the Jamis Xenith Pro hd just landed at HQ.
Geometry wise, the Xenith features fairly standard parallel 73 degree head and seat tubes, giving a trail figure of 58mm. I found this to be a good compromise between a razor sharp crit racer and a more laid back all-day cruiser. Through switchbacks, the Xenith feels quite neutral, neither diving into the corner nor feeling like an oil tanker. To get the best out of it, I found I had to be a bit more active with my weight shifts and really commit to line choices.
All those oversized tubes and the tapered headtube have combined to create a really solid platform for laying down the power. Despite my best efforts, I couldn't coax any chain rub out of the front derailleur. The fork is reassuringly oversized too and handles off-camber corners well; an area where less stiff forks can often be prone to drifting off line.
Despite the overall bike's more laid back handling traits (compared to more aggressive race bike geometry), I found that once you'd committed to a line, the Xenith never wavered from it.
Having praised the Xenith for its stiffness and solidity (the Jamis engineers have obviously made this a priority despite the lower grade fibres compared to the SL), the Jamis never felt like a bike that was eager to be accelerated and chucked around – it merely did its job of transferring pedal and steering input.
This can often be the case when using lower grade carbon and it's this ride feel that distinguishes the real top end, lightweight carbon frames from the rest. They urge the rider on with every pedal stroke and seem to explode forwards at the merest hint of power. The Xenith just doesn't have that spark or pizazz and lacks character in this aspect. This isn't a knock against it per se, and for the price it's a damn fine frame, but it's worth noting that it does lose something to the new generation of super-frames (think Canondale Super Evo and the like). But it also leaves quite a lot of money in your pocket compared to those bikes.
Having spoken at length about the frame, I suspect that the real reason that people are considering this bike is the Ultegra electronic shifting. Functionally, Ultegra Di2 is so close to Dura Ace Di2 as to be virtually indistinguishable with the exception of the front shifts. Here, the off-the-shelf servo motors, as opposed to the Dura Ace version's Shimano designed jobs, are noticeably less quick and powerful leading to slightly slower shifts. When paired with the excellent Ultegra chainrings, front shifts under power are still possible although not 100% guaranteed. When paired with other chainrings, the front shifting is merely slightly better than the cable version.
Does the performance stand up to the hype? I'd have to say yes and would choose the Ultegra Di2 over cable Dura Ace (they both sit around the same price point) for most scenarios due to its reduced lever throw, better ergonomics and fit-and-forget nature. There aren't any cables to get clogged with grime and no housing compression to deal with – all you have to do is remember to charge the thing every 800 miles or so.
What really impressed me most with Di2 was the way it made changing wheels and cassettes, which can often lead to much tinkering with cable actuated shifting, super easy. A 20 second procedure to 'teach' the derailleur the appropriate cog spacing, and you'd have perfect shifting straight away. The stuff really was a joy to work on.
What's good too is the way that Jamis have gone the full hog and completely integrated the electronic cabling into the frame. The shift cables enter just behind the headtube and pop out just before their respective derailleurs. The brain is cleanly zip tied to a brake cable allowing easy access, while the battery sits on a custom mount under the downtube. It all fits together perfectly and cleans up the bike's appearance.
Apart from the main attraction of the Di2, the Xenith Pro features an assortment of basic, but functional components with a few obvious cost-cutting items thrown in. Hey, what did you expect?
The wheels in particular, a set of Shimano's RS10s, are a notch below the rest of the bike. As training wheels, the RS10s perform well as they are stiff, strong and easily user serviceable. Their portly weight on the other hand really detracts from the Xenith's liveliness. Dropping around 500g of rotating weight with some lighter carbon/alloy clinchers led to a significant increase in the bike's responsiveness and playfulness. As always, wheels have a significant effect on the overall bike's character and in this case I'd recommend an upgrade.
Whilst Vittoria may have made their reputation as making some of the best tyres for the pro peloton, I was left extremely underwhelmed with the Rubino Pro Slicks on the Xenith. Whilst they did ok in the dry, in the wet, they were a liability and I managed to consistently loose the back end on turn in. Puncture protection was poor too and the casing seemed particularly prone to slicing. Despite only 2 months use, the tyres are now virtual write-offs such is the number of cuts.
Instead of going with the full Ultegra groupset to complement the shifting, the Xenith comes kitted with some non-series brakes. Apart from not fitting in with the rest of the group visually, I honestly couldn't tell them apart from the respective Ultegra units as they delivered the consistent, well modulated power that I've come to expect from Shimano's latest series brakes. No complaints there then.
Finishing kit from Ritchey is as good as always. I like the way Jamis have gone with the carbon seatpost which, aside from helping in the comfort stakes (maybe), looks just great with the carbon weave shining through the clearcoat. The seatpost clamp is simple but effective and I had no trouble setting up my favoured saddle.
Despite the current trend towards compact shaped bars, Jamis have opted to go with a Ritchey ergo-bend bar. Now, I don't really get on with ergo bars in general, but I found these to be quite comfortable. Reach and drop is larger than a compact, but still not so large as to challenge the less flexible. Bar width is proportional to frame size so smaller and larger riders should find themselves well accommodated.
The Selle San Marco Concor saddle is a nice addition to the overall package and makes a change from the usual Selle Italia which dominates the OEM market. Saddle choice is a highly personal thing and I suspect most buyers will want to swap in their favourite perch, but I found it to be surprisingly comfortable given its narrow width. There's plenty of padding on the nose for on-the-rivet riding and the slightly upturned tail helps to lock you in place whilst climbing.
Overall, wheels excepted, the Xenith Pro's spec stands up reasonably well to the immediate competition and certainly doesn't detract from the frame in any way.
The Xenith Pro Di2 is one of the more accessible electronic shifting bikes currently available. A good, if slightly uninspiring frame and decent finishing kit complement the shifty bits well with only the wheels really letting it down.
road.cc test report
Make and model: Jamis Xenith Pro
Size tested: 58cm
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
The Xenith Pro Di2 is likely to appeal to those looking to dip their toes into the electronic shifting sea without having to get a new mortgage. In addition to the electronic shifting, your getting a frame which Jamis say features "superbly tuned cornering geometry and Euro-style fit geometry"...whatever that means.
Tell us some more about the technical aspects of the product?
Full high modulus carbon fiber, Dyad Ultra lay-up, tri-oval shaped top and down tubes with SST tubing diameters, 1 1/8-1 1/2' head tube, PressFit 30 BB shell, asymmetrical chainstays, twin seat stays, forged one-piece dropouts with replaceable derailleur hanger
Jamis Xenith Comp level, high modulus carbon fiber, 1.5' hollow formed crown, monocoque one-piece forming technology, carbon dropouts with stainless axle interfaces
FSA, integrated, sealed bearing, 1 1/8-1 1/2'
Shimano RS10 wheelset, 16/20H, 24mm rim profile with asymmetric rear rim, RS10 forged aluminum loose ball hubs and bladed straight-pull butted spokes
Vittoria Rubino Pro Slick, 700 x 23c, folding
Shimano Ultegra Di2 electronic IRD-6770 rear and Ultegra IFD-6770 braze-on front with Shimano 34.9mm clamp
Shimano Ultegra Di2 electronic IST-6770 shifters, 20-Speed
Shimano 10-Speed 11-25T
Shimano Ultegra FC-6750. compact double, 50/34T, 170mm (48/51), 172.5mm (54/56), 175mm (58/61)
FSA PressFit 30 with Wheels Mfg. adaptors
Shimano BR561 Super SLR dual pivot calipers with cartridge pads and Shimano Ultegra IST-6770 Di2 STI carbon brake levers
Ritchey Pro Logic II, 7075 triple-butted aluminum, 31.8 x 400mm (48/51), 420mm (54/56), 440mm (58/61)
Ritchey Pro 4-axis, 3D net forged 6061, 6� x 90mm (48/51), 100mm (54/56), 120mm (58/61)
Jamis gel suede tape with Jamis logo and 'J' end plug
Ritchey Pro Carbon, 31.6 x 350mm with Jamis 7075-AL CNC aluminum 1-bolt seat post clamp
Selle San Marco Concor with Microfeel cover and hollow cro-moly rails
48, 51, 54, 56, 58, 61cm
Palladium Silver/Natural Carbon
The frame seems to be well built and there weren't any paint or clearcoat flaws to be seen
The best way to describe the Xenith Pro frame is: "pretty good". It does all the basics well but just lacks that character and lively ride quality which would make it "great".
The Ui2 is genuinely a game changer. Not only is it functionally excellent, but it's also super easy to work on.
Really, it's the wheels which let the bike down and an upgrade to something lighter would surely go some way to improve that aforementioned ride quality.
There have been some concerns voiced about the durability of electronic shifting in wet conditions, but my experience shows that these are the conditions in which it very much outperforms cable actuated versions. All the connections are well sealed to the appropriate IP ratings so there should be no troubles there
Overall, the Xenith Pro is quite a bit heavier than other bikes in this price bracket. The Ui2, which is about the same weight as 105, and the wheels are the main culprits here
Comfort wasn't something I really noticed with the Xenith. It wasn't overly harsh but it didn't blow me away either.
This is a difficult one. Whilst its just about the cheapest carbon-framed Ultegra Dii2 bike out there, its in serious need of a wheel upgrade which wouldn't come cheap
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
About the tester
I usually ride: Giant TCR Advanced 2 My best bike is: Canyon Ultimate CF7
I've been riding for: Under 5 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: road racing, sportives, mtb,