SILT CARBON AM WHEELSET REVIEW

SOLID BUDGET CARBON HOOPS

Review by NE Scotland Shredders | Photos by Robert Johnston

The Carbon Fiber wheel market is vast by now, with a range of bank-breaking options to satisfy the needs of just about every mountain biker. In the price bracket of a premium alloy wheelset though, carbon options are not extensive, so many will turn to the tried-and-true metal hoops if dropping big money isn’t an option. That said, there are a few companies making more budget-minded carbon fiber-rimmed wheelsets, such as SILT. They have a range of carbon or alloy wheels for various disciplines, and we tested their $1k Carbon AM wheelset between a few riders on the UK and European enduro race circuits to see how they perform. Despite the traveling, it was no holiday for these wheels, but they came out of the other side unscathed, mostly.

THE LAB

The SILT Carbon All-Mountain (AM) wheelset is targeted at the hard-hitting Enduro mountain bike crowd, designed to tackle the most testing courses with confidence, while coming in at a relatively affordable price tag when compared with some of the big names.

The SILT Carbon AM wheels use a carbon fiber rim with 38mm external width and 24mm depth, featuring a 31.2mm internal width ideally suited to 2.3-2.6” tires. The sidewalls and spoke holes are reinforced to provide the required strength for enduro punishment, with 4-D precision drilled spoke holes to distribute the spoke nipple forces equally around the hole. The rim bed is given a ramped design to aid in tubeless tire seating, and there’s a bead lock ridge on the sidewall to improve tire bead retention when pushing hard at low pressures. The rims are connected to the hubs with 32 double-butted (2.0mm – 1.8mm – 2.0mm) j-bend Pillar spokes in a 3X pattern for maximum strength, which are secured to the rim with double square head alloy nipples.

The hubs are CNC’d aluminum, with the same 4-D precision drilling in the j-bend spoke holes, and spin on high speed Endurance bearings. The rear hub is the main talking point here, featuring their exclusive Ratchet Drive system with a heat treated 36T stainless steel drive ring that provides a 10 degree engagement. This is similar in operation to the DT Swiss Ratchet EXP system, which has been proven on wheelsets across the globe to provide dependable engagement. The hubs are available in all major standards of spacing aside from SuperBoost, with SRAM XD, Shimano HG or Microspline freehub body options.

The SILT Carbon AM wheelset is supplied taped ready for tubeless, and tubeless valves, spare spokes and nipples are included in the box should the need arise. There’s a combined bike and rider weight limit of 130kg. The wheelset is backed with a Lifetime crash replacement policy that will provide a replacement component to the original owner in the event of a crash. The Carbon AM wheelset can be purchased in 27.5”, Mixed wheels or 29” options, with a retail price of $967 or £800 for the pair, direct from the SILT website.

THE DIRT

Over the course of testing, the SILT Carbon AM wheelset has been passed between a few of the fastest riders in the Northeast of Scotland, and they’ve taken them across Europe to give them the ultimate test. From the infamous Megavalanche to enduro racing on both the European EWS rounds and Scottish races, it’s been as tough of a test as it gets.

The Carbon AM wheelset tipped the scales at 1831g for the pair of Microspline freehub-equipped 29ers, including the preinstalled rim tape. Everything looked neatly finished with no rough edges or obvious flaws in the carbon, and the hubs span smoothly. The freehub was exceptionally loud out of the box, with a very solid sounding “clack” to the ratchet drive mechanism that gives the impression of solid engagement.

The initial impressions of the freehub rang true when the SILT wheels were mounted up – it’s loud, super loud! This can be an opinion divider, but it was easily made quieter with some additional grease. The testing crew was divided by it – some really enjoyed the loud hub sound, but if this is you then be ready for plenty of comments from other riders in your group! There was no need to struggle and swear when setting up tubeless tyres on these wheels. The 31mm rim width and the tubeless-focused profile worked great when fitting tyres from various brands with or without an insert, never demanding the use of a compressor to get the bead seated.

On the trail, all riders reported the same when it came to the performance and feeling of the SILT wheels. When riding a bike park or trail center style trail, the SILT AM rims gave a very responsive ride, which could noticeably reward confident riders with plenty of corner speed through berms and big trail compressions. This responsiveness carried over to the pedaling feel of these wheels. Getting on the pedals out of turns and on flat sections of trail, the bike really wanted to giddy up and get down the trail, giving a nice “released spring” feeling that rewarded the rider when accelerating. This was complemented by the solid freehub engagement, and made for a sporty feeling ride.

The responsive ride feeling was not to all reviewers taste, negatively impacting front wheel tracking when compared to an alloy wheel – especially notable on wet rooty trails. This was most noticeable when hitting bumps with the bike leant over in the middle of a turn. The feeling that the front wheel wanted to lift upward out of the berm or push straight on in flatter turns made for a little bit of nervousness at times, especially when riding tracks blind. When charging hard on drier trails this effect was less of a hindrance, however when conditions were not ideal or on trails with lots of small to medium bumps at a high frequency, a softer more compliant front wheel setup was definitely preferable to help keep steering smoother and more predictable. This might not affect heavier riders, as much as all riders in our test were in the 70-80kg bracket.

Often for the most important runs, the crew would opt to run an alloy wheel in the front with the reassuringly solid SILT Carbon AM wheel in the back, giving a good blend of handling. This is perhaps where the largest difference between the SILT and some more expensive offerings lies, as the more expensive offerings often come with either front and rear-specific rims, or different spokes or spoke counts at minimum to tweak the stiffness-compliance balance to deliver the desired front wheel grip.

Throughout the whole test we only had 1 spoke snap on the wheels and it was from a loose rock strike, luckily SILT provided spare spokes in the box so the fix was simple. The test team didn’t have to tighten any spokes for the majority of the test period, even after a week of Megavalanche rock bashing in Alpe D’Huez. It wasn’t till the last few months of the test where the back wheel needed a re-tension, which was a breeze on the carbon wheel with nearly no need for truing only tensioning. The lack of spoke tensioning and tinkering required far exceeded our expectations, and was undoubtedly the highlight of riding the wheelset. Riding a premium alloy wheel in the same Alpine conditions we would expect to be checking the spokes every couple of days, if not everyday. After all the testing there are still no signs of cracks or damage to the rims, but there is lots of cosmetic scratching as expected after months of hard riding – these wheels have been through the wars and come out the other side swinging. The SILT Carbon AM wheels would be a perfect choice for a privateer racer or bike park basher who craves great reliability and minimal maintenance without sacrificing reliability. Even the factory taping was perfect and has lasted many tire changes, still going strong!

We found the threaded freehub axle could back off after time, and was left wondering if SILT were constricted to this design due to the axial freehub. The testers have put similar time on Hope Pro 4’s this year without doing more than re-greasing the freehub once or twice, so it has to be said that there was definitely more tinkering required with the SILT hub. Re-tightening could be problematic without the right tools, as it required a 17mm cone spanner on the drive side and something to fit into the unrefined-feeling hub axle slot on the non-drive side. We feel this rear hub design could be tweaked to help reduce maintenance. Finally, we experienced a rear hub axle failure during testing. SILT were beyond helpful sending out the tooling and parts to repair this, and it has to be said that the failure happened in the Alps, after what would probably be most people’s equivalent to several years of riding in the UK. Nevertheless it happened, and could have been troublesome if the tester didn’t have a spare wheel to use in the meantime.

SILT took the broken axle very seriously, asking the test crew a number of questions to identify the cause of failure and requesting the broken axle back for inspection. Their response read:

“We have been looking into this further and we think the reason for the axle break is to do with the rear axle used on Specialized Enduro bikes. These seem to have a tapered section for most of the middle section which creates a gap around the bearing’s seated position. This is the location where most of the rider weight is transferred and for some reason, the loading may have caused the sub-axle to break. Most bikes on the market run straight axles so consumers riding anything other than a Specialized Enduro will have no issues at all. For those that do run Enduros, we would advise they run a straight thru axle.”

With a considerable amount of test time spent on two Specialized Enduros, it’s understandable that the unique loading produced by the tapered axle may lead to such a failure, and you can’t really argue with their durability other than this incident.

The Wolf’s Last Word

The SILT Carbon AM is a very reliable wheelset with a great overall ride, only hindered by the slightly unrefined rear hub and slightly too stiff front rim for all-out tech trails! At their relatively budget price point, riders who can handle the stiffer front rim will likely be well served.

Price: £800 /$967
Weight: 1831g (29”, Microspline, With rim tape)
Website: Siltmtb.com