The RAMAX has proven a fast and comfortable bike for long day rides. So far, the longest trip has been the 300km Beef Line/Green Furusato Line brevet in Ibaraki. I have not yet ridden it on 400km or longer rides because of the lack of a front wheel with dynamo hub that fits with the 12mm thru axle and disk brake specification. For a 400km or longer ride, I don't want to worry about battery life for my front light. Problem now solved!
On Friday, a beautiful new set of handmade GS Astuto EV36+ wheels arrived.
The carbon rims are WIDE, 32mm outer width, and 36mm deep. For comparison, my typical Velocity A23 or H Plus Sons Archetype rim, which once were considered "wide" rims, similar to the early HED Belgium rims, have a 23mm outer width. The GS Astuto EV36+ are more like the Miche Graff Route wheels ridden by the winner of last week's Gravel Unbound, Ivar Slik. as he went 200 miles (322 kms) on a variety of surfaces at an average speed of 34.4 kph. They are a similar hookless carbon rim, 36mm deep, 30-32mm outside width. Even the current Zipp 303 Firecrest tubeless rim, which has a definite "road" racing heritage, now has a 30mm outer width.
Since the EV36+ rims are carbon, hookless and disk-brake specific, they can be both very light and strong. Indeed, the box they arrived in felt ... as if it were empty!
Hookless rims are lighter weight and easier to manufacture than hooked ones. They should only be used with a compatible tubeless setup and at lower pressures than a typical road bike. Given the width, of course, they must always be used with larger width tires that are designed for lower pressure. (The tires should be 30mm wide or greater to fit the EV36+ rims.) Hookless rims will help drive the high end of the cycling market toward the conclusions Jan Heine of Bicycle Quarterly/Rene Herse has been preaching the past decade in numerous Bicycle Quarterly articles and his book, The All-Road Bike Revolution: wide supple tires run at lower pressures are as fast or faster, and a lot more comfortable, than narrower tires run at higher pressures.
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| The RAMAX finally as it was intended--An all-road adventure bicycle. |
Both front and rear wheels have 24 Sapim CX-Ray spokes. CX Rays are the best spokes by far, in my experience. They combine strength, light weight, and aerodynamics. Unbeatable. Not cheap, but worth every penny. I used to break spokes regularly. When I switched to building (and in this case, having built for me wheels with CX Rays ... the problem pretty much went away. For an aluminum clincher rim, I would hesitate to use a 24-spoke rear wheel, even with CX-Rays, but for these wide, deep and stiff rims, with fatter tires running a lower pressure, a 24-spoke setup should be fine even for challenging, off-road conditions.
The rear hub is an OEM/private label model made for GS Astuto, and the front is an SP Dynamo PL-7. The hubs are for Centerlock disk brake rotors -- Tim Smith tells me that the Centerlock design, a Shimano standard, is better, and I now agree. It is a lot easier to put the Centerlock rotors on (and take them off) and to get them in exactly the right position than with the 6-bolt style I am accustomed to using. And indeed, the weight of the dynamo hub for Centerlock is 10g lower than the corresponding 6-bolt style from SP Dynamo.
The PL-7 is SP Dynamo's newest model, released just before the pandemic. It is about the same weight as the SV-8 models I have used in the past, but offers more power output at the same speed. It is noticeably lighter than SP Dynamo's previous disk-brake specific versions, but it looks and feels just as solid. The hub is designed for the now-common 12mm thru axle specification, which offers the possibility of a stronger axle than a 9mm QR. (Some hubs can be converted between QR and 12mm thru axle by changing the end caps, but most older hubs cannot).
For tires, one of Tim's suggestions was the IRC Boken Plus 700x32mm version. It is a gravel bike tire with a slick middle strip so that it can go fast on tarmac as well as handling rough or muddy surfaces. IRC is a Japanese brand that is not as widely known as some European tires (Conti, Vittoria, Michelin, et al), but IRC was one of the early adopters of road tubeless technology. IRC stands for Inoue Rubber Corporation -- headquartered in Nagoya and with production facilities in Sendai as well as in SE Asia). The Boken Plus has gotten some good reviews so I was happy to try them. They feel as if the side walls are relatively supple -- crucial to making a tire fast. And IRC has a lot of experience with tubeless -- these hold air extremely well and, Tim reports, set up very easily.
Matched with the wide EV36+ rim, the tires actually measure at 35.5mm width -- and seem to have a large air volume similar to the 700x36 Challenge Gravel Grinder tires that were on the loaner wheels when I first got the RAMAX. So while, for gravel tires, they are near the "narrow" end of the spectrum, for me they are huge. I inflated them to 55psi or 3.8 bars of pressure. I will try 45-50psi or even lower for rough surfaced roads. But years of riding at higher pressure has gotten me stuck in my ways, and it will take awhile to change the prejudice that a tire needs to be "hard" to the feel to be fast.
I took my first long ride with the new wheels on Saturday -- 200 kms entirely on tarmac. The ride feel was comfortable and smooth as silk. My overall moving speed for the day, 23.5 kph, was about what I would have expected for a 200km ride with ~1500m of elevation gain, a long gradual uphill grind and much less downhill, in humid weather. If I struggled at times, it had more to do with the humidity and that farewell party for a friend that I attended the night before than it did the wheels. Indeed, the wheelset is so light that even with the heavier gravel tires they do not feel heavy or sluggish -- a feeling that has turned me off of gravel tires in the past. Even with the gravel wheels, the bike still climbs well, and it descends like a dream on tarmac. What once might have been a kind of "white knuckle" descent at high speed at the end of the ride, was very relaxed though my top speed seemed no different.
I look forward to many years of riding with this wheelset. Tim is already suggesting that I might want to try them with a pair of super supple, lighter Rene Herse tires at some point ...but for the time being the Boken Plus will do just fine.
