I was looking over my shoulder for traffic the other day coming down a lovely, long hill on a local road that is designated a truck route, and thus has some nasty pot holes. This one I've avoided for over a year now, but my timing was just a bit off and I ended up in it because I couldn't swerve out to avoid it - traffic.
This pot hole isn't completely round, having a small peninsula jutting out from the edge, anchored by a single large stone, which put a pretty good dent in my Easton R90 SL's brake track on the front wheel. I expected the wheel to be out of true, so coasted to a stop with a little help from the back brake to open the brake calipers - the OTHER use for that little lever do-hickey (or fizal contuzer, take your pick).
To my surprise, the wheel, clearly dented, and the bead warped enough to affect the tire's bead-lock, was not out of true, AT ALL! Once home I inspected it carefully, and can't detect ANY deflection in the wheel at all. I know wider rims are supposed to be stronger, but OMG, this would have destroyed most wheels. I have to say, if you're building wheels for touring, long miles, or gravel grinding, the Easton R90 SLs are really TOUGH.
I decided to remove the tubed tire off the front wheel that came with my Pinarello, and mount a ContiGP5KTL, using the Folcrum 5's stock rim strip and adding a Stan's valve. The tire went on with no tools, and a good bead-lock, but the Stan's valve really sucks. It wouldn't seal up, and the sealant probably ended up inside the cavity in the rim, so not happy with that Stan's product at all. Otherwise, their rim tape and sealant is excellent. The problem is Stan's valves are sized for tubeless rims, and flop around like a jelly fish in the oversized holes of tubed rims.
CORRECTION: The valves and inner-tubes do indeed fit my replacement Easton rim. Not sure why the holes are bigger on "Universal" or tubed rims, but they no longer need to be AFAICT. Just FYI.
The Fulcrum 5 is a standard width rim, with a straight-pull, no-flange hub and 18 bladed spokes. I have to say, while nowhere near as strong as the 24 spoke, 2X laced Easton R90 SL + Chris King wheel I had custom built at Colorado Cyclist, it did seem a tad more aero, and stood up a bit taller to roll over the 3-5" gaps in the road common around here. In fact, it's given me a whole new appreciation of straight-pull front wheels.
The advantage to straight pull is all the spokes are in the same plane, vs being on one side of the flange or the other, creating a rather messy aerodynamic shape from the hub to the 1st cross. With radially laced spokes, and straight-pull hubs, all the spokes are all in a row, from hub to rim. Especially with bladed spokes, this eliminates one of the few remaining sources of drag due to spokes. Flanged hubs like the Chris King R45 CAN be laced radially as well, with all the spokes laced on one side, usually to the spokes are on the inside of the flange, and heads on the outside, but still not quite as clean as a no-flange, straight-pull arrangement.
The Easton wheel didn't lose any extra air overnight, my concern in riding it, but I think I'm going to ride the Folcrum 5 wheel for the rest of the month and see how that goes. There may be a straight pull front wheel in my future. Both the DT Swiss 240 and 350 (Taiwan, not Switzerland) look nice, the 240 looking nicer to me, but not sure I want to pay $125 premium to lose 5 grams of weight. The Fulcrum will do for now, and should make a good test-bed.
BTW, Fulcrum has put some interesting tech in the rear wheel of the Fulcrum 5. The rim is deeper, the drive-side flange is HUGE, the spokes are all in-line, and the spoke-beds are offset in the rim like the DT Swiss 411s are. The non-drive side is radially laced, straight-pull, and to a no-flange hub side. All of these features work to minimize the asymmetrical spoke tension created by every-growing cassette cog counts and the attendant increased dish of the wheel.
It's over 200gr heavier than my Easton-King wheelset, but if you weigh less than 165 lbs they'd be a good choice for a bargain wheelset.
It will be interesting to see how the front wheel performs. I'll check in with observations now and again when there's something worth remarking on.
Cheers!
PS:
It's mid-January, 2021 and after switching back to the custom Chris King wheel in Oct for my COVID replacement Century, I am still riding it. The Easton rims are more aero, enough so that the entire wheel is more aero, though hard to detect this until ~ 20+ mph net wind.
What I really didn't like was the straight-pull wheels' tendency to "buzz" back and forth 1-3mm the entire time I was rolling, and I think this is just a characteristic of straight-pull wheels where any change in spoke tension from course road surface gets translated into side to side motion. It's a bit like "Dutch Roll" in flying. It's annoying to me, but more importantly, it probably wastes energy to drive all that high-speed movement of wheel mass. A lighter rider might have a different experience.
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