FIRST LOOK: Bouwmeester Tammar V4.8 Carbon Wheels

Carbon wheels are so hot right now. What was originally a slow burner for the mountain bike market (see what I did there??) has now turned into one of the most sought-after upgrades. Thanks in part to brands such as Reynolds and ENVE, carbon mountain bike rims have largely been proven in the dirt, offering up greater strength and increased lateral stiffness over their metal counterparts. Lighter rim weights have also been made possible, and many riders who upgrade to a carbon wheel set cite the lighter weight and improved acceleration as being one of the most noticeable performance advantages.

That said, there is carbon, and then……there is carbon. Not all wheels are created equal, regardless of whether they use the same material or not. Carbon rims can still break, and poorly designed carbon rims can offer a harsh and unforgiving ride that detracts from your bikes ability to lay down traction where it counts. Components are also rapidly evolving, with bigger forks, fatter tyres, stiffer frames and wider handlebars changing the load demands on the bike’s rolling stock. Seeking to build a better wheel for the modern trail bike, Bouwmeester Composites recently debuted their brand-new Tammar wheel set. Designed, engineered, and built from the ground-up in South Australia by Bouwmeester Composites, the Tammar V4.8 has many unique features and design elements that stand it apart from the “me-too” carbon rim crowd. Aside from its local manufacture, what exactly is the difference between the Tammar V4.8 and other carbon wheels? Well, you’re about to find out!

“Two years of R&D, extensively lab tested, raced and proven with some of Australia’s best riders; the Australian made Tammar v4.8 race rim is here. It boasts better ride characteristics, improved tyre support, rolling resistance and grip. The optimum balance of torsional stiffness and global wheel stiffness need to be met to offer the perfect performance. Our Tammar v4.8 rim design profile can absorb impact energy and improve tracking and tyre traction. Better traction means faster riding. The rim is a solid profile, similar to motocross rims, which, from a carbon engineering perspective, means the fibres are supported correctly through an optimised laminate. This gives the rim it’s superior toughness out on the trails. This leaves the current traditional MTB rim design, which is a carry over from aluminium rims and manufacturing processes adapted from carbon road rims. To optimise the perfect rim we reviewed four key design elements (Learn more) and what BC developed was the first wide platform solid profile carbon rim in a hookless bead format for 27.5″/650b.” – Bouwmeester Composites

The Bouwmeester Tammar v4.8 Wheelset features:

• Solid profile rim for increased impact and spoke hole strength
• Front and rear specific carbon layup
• Shallow rim and race tuned carbon lay-up for improved tracking and traction
• Asymetric rim for improved even spoke tension
• Rim width: 38mm external, 31.5mm internal
• Rim weight: 480 grams (front), 490 grams (rear)
• Wider platform rim to correctly support tyre sidewall for performance
• Superior cornering grip and improved rolling resistance
• Hookless bead increasing inner rim width and tyre wall support
• Spokes: DT Swiss Competition
• Hubs: DT Swiss 240 (15mm front & 142x12mm rear)
• Claimed wheelset weight: 1750 grams
• RRP: $3499

First things first; the Tammar V4.8 rims are wide! Following the recent trend of pushing internal rim widths wider and wider, the Tammar’s measure up over 31mm internally and 38mm externally. They feature a hookless profile, with each sidewall being made from 3mm thick carbon fibre. They use an offset profile with a central channel that’s designed to provide easier tubeless inflation. Our test set turned up with tubeless tape and valves pre-installed. In terms of installation, I should point out that both tyres aired up tubeless with just a floor pump. As the beads on the rear tyre climbed out of the central channel, they locked into place at just 22psi. The front tyre beaded at just 18psi. That is bloody impressive!

As with any wide carbon wheel though, the broader bead platform will have an effect on the profile of the tyre being fitted. And not always for the better. In the case of the Tammar V4.8 wheels, they were replacing a set of Reynolds Carbon AM wheels that I reviewed for the most recent issue of AMB Magazine. Those rims use a 23mm internal rim width. That’s not skinny by any stretch of the imagination, but it is a good deal narrower than the Bouwmeester Composite rims. Despite the change in rim width, the 2.3″ wide Maxxis High Roller II tyre grew just 2/3 of a millimetre when fitted to the Tammar V4.8 rim. Not a huge difference, but a change nonetheless.

Out the back, it was a dramatically bigger difference. The Maxxis Ikon 2.35″ tyre blew up nearly 3mm compared to when it was mounted to the Reynolds AM Carbon rim. This goes to show that every tyre behaves a little differently depending on the type of rim its fitted to. Some tyres benefit from being fitted to a much wider rim, and some tyres don’t benefit so well. In the case of the Ikon, the risk we now run with this tyre is that the casing actually sits wider than the tread. That means I’m more likely to have the tyre let go under hard cornering loads, as the casing ends up contacting the ground as the wheel is leaned over further. Of course I’ll be confirming this through testing, and I’ll also be fitting other 27.5″ tyres to see what works well and what doesn’t work so well on the Tammar V4.8 wheels.

Once wrapped with rubber and fitted to the bike, the Tammar V4.8 wheelset offers a very unique profile. Compared to other carbon rims that use massively deep profiles, the Tammar’s are very shallow in comparison, and more like a moto rim. In fact, that was Bouwmeester Composites’ inspiration during the design and prototyping phase of the Tammar rims. Instead of a traditional hollow shape, the rims use a single-wall construction that allows the carbon fibre to be layered up super-thick.

There are sound engineering principles behind the shallow rim profile, though compliance was one of the main design goals for Bouwmeester Composites. Many carbon rims on the market deliver on being lightweight and stiff, but having a carbon rim that is comfortable is an entirely different thing all together. The Tammar V4.8 is designed to provide good lateral stiffness, but it’s also purported to offer greater vertical compliance and a smoother ride. Time will tell on those claims…

At this point in time, Bouwmeester Composites are only offering complete wheelsets. That’s not a bad thing, because the Tammar V4.8 is laced with double-butted Competition spokes from DT Swiss, and features bulletproof 240 hubs. Interestingly, the front rim is slightly lighter than the rear rim (10 grams) and uses a different layup to cope with different loadings compared to the rear wheel. Bouwmeester Composites have laced up the rims with a standard 3x build and 32 spokes per wheel, which I dig a lot. Non-proprietary spokes and nipples FTW!

Weight-wise, the Tammar V4.8 won’t blow your mind. For the complete wheelset with tubeless tape and valves, they come in at 1840 grams. When many brands are touting the grammage of their premium carbon wheelsets, that figure may be a little disappointing. However, this is a set of wheels that is designed to offer ride quality and strength over all else, and it’s not exactly aimed at the weight-weenie XC crowd. Most experienced riders understand that weight is only one factor in a wheels performance on a mountain bike, and so it isn’t necessarily the focus here.

The 150mm travel Torrent CS from Avanti Bikes will serve as the primary test-sled for the Tammar V4.8 wheels, and in it’s current guise that you see in the above photo, only the wheels have changed over its previous setup. With the same suspension setup, the same cockpit setup, the same tyres and the same riding position, this will provide us with a perfect opportunity to benchmark the Tammar V4.8’s against the recently tested Reynolds AM Carbon wheels, amongst others. Keep an eye out on AMBMag.com.au for further updates on our longterm test bike, and make sure you subscribe to the magazine to get your copy of the full review and tech feature on the Tammar V4.8 wheels.

Bouwmeester Composites

Website: www.bouwmeester.com.au

Email: info@bouwmeester.com.au

Phone: +61 478 660 048