LEW wheels

[alienator]

If you go to the end-ish part of this thread, I have three posts that cover what I remember of my visit to LEW Racing today and the meeting I had with them re: their new wheels.

Iffin' you read it and have questions, ask.

 

[gil99]

Can you explain the trip structure which helps reestablish boundary layer flow? I can't picture what is going on.

 

[alienator]

Can you explain the trip structure which helps reestablish boundary layer flow? I can't picture what is going on.

I'll post a pic of what happens. Give me a bit of time.

 

[gil99]

Went back to FWB and LEW and read more. Swirl lip gen I'm guessing is like a vortex gen on aeroplane wings? Anyway, if so, that's tres frickin' cool!

 

[alienator]

Ok, I've attached a jpeg that shows where and kind of what these spoke face swirl generators are. In zero wind or in a head wind, these things don't do anything, however as the wind starts quartering, i.e., coming from the side, they cause the boundary layer flow to become turbulent. The reason you'd do this is that done correctly it'll help the boundary layer flow of air reattach on the downwind side of the rim, thus reducing drag. In these conditions that translates into less sensitivity to crosswinds and a bit more forward go juice.

Okay, so I forgot to attach it. Now it's here.....

Also, in the sketch, nothing is to scale. The spoke face swirl generators are exaggerated and drawn to give a general idea of what they are/where they are. They don't protrude nearly that much on the actual wheels, and as best as my fingers could tell, their profile is different. I'm guessing they're about 0.5-1mm tall or so.

 

[gil99]

Very lustworthy. Any time for more questions?

 

[alienator]

Very lustworthy. Any time for more questions?

Ask away.

 

[gil99]

Is the spoke/rim interface conducive to building up a set with steel spokes?

 

[alienator]

Is the spoke/rim interface conducive to building up a set with steel spokes?

Well, they're selling individual rims, now, so the answer would be yes. While there, I was shown a rim built up with DT240's hubs and DT Revolution spokes. Very nice.

The only difference between the rims in the complete wheelsets and the rims sold individually is the shape of the spoke hole.

LEW has individual rims priced at $600 I think, so that's inline with Zipp's rim prices. According to LEW, by June 15th, they'll be producing 18 individual rims a day, in addition to the 4 complete wheels a day. They guarantee that each rim will be less than 300g, and they say that nearly all the rims are coming out weighing 'round 270ish grams.

In the fall they're releasing, at Interbike, an all boron wheelset which will weigh 'round 700ish grams. I suspect that they'll then also start selling individual boron rims.

 

[CAMPYBOB]

They guarantee that each rim will be less than 300g, and they say that nearly all the rims are coming out weighing 'round 270ish grams.

In the fall they're releasing, at Interbike, an all boron wheelset which will weigh 'round 700ish grams. I suspect that they'll then also start selling individual boron rims.

Wow. I am impressed. I'm really not much of a weight weenie, but that is a very nice set of wheels. Give it two years and I'll be able to justify the lower cost of the trickledown technology.

 

[alienator]

Wow. I am impressed. I'm really not much of a weight weenie, but that is a very nice set of wheels. Give it two years and I'll be able to justify the lower cost of the trickledown technology.

I don't think you'll have to wait two years for the price to come down....

 

[gil99]

The spoke face swirl generators are exaggerated and drawn to give a general idea of what they are/where they are. They don't protrude nearly that much on the actual wheels, and as best as my fingers could tell, their profile is different. I'm guessing they're about 0.5-1mm tall or so.

Alienator, are the generators one continuous lip around the entire circumference of the rim? Or, are there many raised generators per side?

 

[alienator]

Alienator, are the generators one continuous lip around the entire circumference of the rim? Or, are there many raised generators per side?

One continuous lip around the circumference on each side.

FWIW, Paul Lew has a variation designed that will use an active form of boundary layer control instead of the passive generators.

 

[rudycyclist]

Alienator, did you get a chance to ride the wheels at all? How did they corner/handle/feel overall? At such a small weight, you'd think the stiffness of the wheel would be lost like most on the market now.

 

[alienator]

Alienator, did you get a chance to ride the wheels at all? How did they corner/handle/feel overall? At such a small weight, you'd think the stiffness of the wheel would be lost like most on the market now.

I was to have come home with a set of v1.0 wheels, but since they released the v2.0 wheels just before I went up there, my test wheels are pushed back a bit. I'll get to take a spin on a set in 2-3 weeks, and then some time after that I'll get a set for a longer test.

I do not believe stiffness will be an issue. The boron matte used is very stiff. LEW said their hollow boron axles were as stiff as steel axles. I handled a sample of unidirectional CF matte and a sample of boron matte. While the boron matte was roughly 1.5-2 times as thick, it's stiffness along the grain of the matte was at least an order of magnitude (10 times) stiffer. I'd not be surprised if the stiffness was actually higher than that. Flexing a VT-1 Pro rim compared to a LEW Sydney generation rim, I guesstimated the VT-1 Pro rim to be 2-5 times stiffer laterally.

The reason for using the boron matte in the layup is exactly because of its stiffness and lightweight. Note that the VT-1 Pro rim that I fiddled with weighed in at 275g when I put it on the scale. A huge added benefit to the boron matte is it's compression stiffness and strength, which significantly exceeds CF. This should translate to a rim that has much better impact resistance than similar CF rims. It's worth noting, too, that the spokes are also made of CF and boron, with two spectra cords running the full length inside to hold things together just in case sh*t happens in a really big way. The spokes I fiddled with were also freaking stiff.

 

[bobbyOCR]

just came back from an 8 day outward bound course so I got a little catching up.

If LEW have shipped the wheels which a friend had ordered a while back over here, I can post more pics of any details which are wanted. They look like an amazing set of wheels.