Fulcrum 1 vs Mavic Ksyrium SL - Page 2

In what way are capmy hubs NOT better than mavic hubs?

Campy hubs look better int he first place IMO.
Campy don't use a bush in the freehub
Campy use better seals
Campy use fantastic rolling adjustable cup and cone bearings (Mavic use modest sealed bearing units, more seals+ more drag)
Mavic have the driving spokes on the non drive side to try and improve the dish on the real drive side. I'd say this would make the wheel weaker torsionally. Campy's spoke mountings are far more effiencent, and the G3 drive side makes the wheels very good at putting down power for a low spoke count wheel.

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Precision Sports

What he said - Mavic use a cheap plastic bushing instead of a proper set of bearings in their FTS-L hub - primarily to keep the weight and costs down. Crappier seals and bearings as well. More drag and less adjustment.

This means the mavic freehub also needs to be pulled apart and serviced every three months if it is going to last. First time I serviced mine I couldnt beleive how much crud had got in there in three months.

It also has two pawls compared to three on the campy hubs. So it doesnt sound as good when you are coasting

In Aust atleast the Fulcrum 1s were cheaper than building a set of DT240/1.1s by a few hundred dollars. Weight wise not much difference.

Would agree that the Dura Ace wheelset is value for money given what you get. If it was blinged up a bit more it would get higher prices.

The Fulcrum 1 is essentially a Campy Eurus minus the G3 spoke pattern. G3 does look good but with the huge acerage between the spokes you have very little to play with if it needs truing.

Fulcrum calls G3 2:1 spoking and uses it on all thier wheels. Fulcrum wheels are basically the same as campy, very few differences across the range from the racing 3 upwards.

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Precision Sports

Is there a real need to replace the FTS-L freewheel body kit every time you take it apart? And what is the spec of the mineral oil used for the lube? Any comments on these?

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Morphed Bianchi Camaleonte IV 2006, Ridley Damocles 2006, Garmin, Mac

No need to replace it if the bushing is still ok and the pawls working properly. Just need to clean out the crap, make sure you keep all the fiddly bits together and then lube it with mineral oil. Your LBS will advise what is suitable and the Mavic brand is not necessary.

On the spoking I was refering to the 3 pattern spoke group that Campy use on Campy branded wheels - this pattern isnt used on Fulcrum. Other than that the F1 is a Campy Eurus.

I love them.

i have DA 7801 wheelsets on two of my roadies. Excellent wheels. No complaints even with alot of mileage over roads of varying conditions.

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How absurd that a supposedly top-end wheel needs all this!! I'm used to freehubs that you put on the bike and neglect completely over 15 years...Exactly how much weight saving does this inferior design achieve? You've cured my lust for a pair of Cosmic Carbones! When are Campy/Fulcrum going to bring out an Al/composite deep section rim that doesn't cost the earth?

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"All that we see and seem is but a dream, within a dream..."

I get what you mean now the three "paired" spokes on campy, compared to 2:1 spoking but not "paired"
I'm embrassed to say I hadn't noticed Fulcrums aren't "paired"

I'd actually like to get a 36 hole DA hub and only use every second hole on the non drive side to produce a 2:1 24 spoke rear wheel. Not too many 40 spoke front hubs around to do the same on the front to produce a 20 spoke front (DA doesn't come in 20).
Other option is 27 or 30 holes on the rear, and 24 on the front, but where do you get 27 or 30 hole rims with out a custom drilling ($$$$$$)?

Yeah Yeah I know nothing wrong with standard wheels. I have Zondas and I just think the 2:1/G3 is cool and a good idea.

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Precision Sports

I do also prefer decent hand built wheels - one of my fav wheelsets in my stable is from '93 and is Campag Record (8sp cassette) on Mavic Open 4 CD Ceramic rims

but, of all the factory wheels I have seen, I do like some of the Vuelta range. Not sure how they compare to top end Mavics etc. but I have set of Cheap Vueltas that I compared with Aksiums for winter that were about £90 all in and they are just great.

I beleive it saves a whole 50 grams or so and a few bucks on a set of bearings. Go look at the pdf on the mavic site that shows how to service the FTS-L hub. The plastic bush is there for all to see.

Yeah but only deep section past 35mm. Alloy rims As far as I know go to 30. The only way to start gettin an aero advantage is to go to or beyond a 2.5:1 depth to width ratio. On a 30mm rim that is a 20mm wide tyre. I run 23mm as I like the comfort and reduced rolling resistance, plus the better handling. So I'll take the lower weight and minimal aerodynamic difference of a box section for the moment. If I go deep, it'll be 38mm+ and carbon.

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BMC SL01
SRAM Force


thank you crank n' cycles...If you are ever in SW WA, take a trip to Crank N' Cycles.

Personally, I'm going to buy a set of these:


http://www.excelsports.com/new.asp?page=17

Bobby, I'm not in a position to dispute this, but can you cite your source? I've not seen this before; people typical talk about absolute depth rather than ratio. Can I run 25mm tyres with Zipps at no air drag cost?
Spoke number and bulk are probably at least as important as depth, hence the poor aerodynamic performance of your Obermayers.

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"All that we see and seem is but a dream, within a dream..."

I don't agree with Bobby that there is a "tipping point" or optimal ratio, but the trend is clear. The deeper your rim, the better. But there are diminishing returns as you get deeper and deeper until the wheel becomes a disk. And as Shimano has shown with their Dura Ace wheels, a fairly short rim can have excellent aerodynamics. How!?

It might be more helpful to think of your tire as the leading edge to an airfoil. As the air hits the tire, it splits and flows around it. If there was no rim, then at some point on the back side of the tire the air will separate from the tire and become turbulent. This makes a low pressure zone of turbulent air behind the tire. High pressure at the front of the tire, low at the back - this results in a net force backwards - drag.

Now put a rim behind the tire. If the rim starts out at roughly the same width as the tire, then the air will not separate, but follow along the surface of the rim. Of course, if the backside of the rim ends abruptly (like a box rim) then the air will separate again leading to turbulence and drag.

Now imagine the rim as slowly tapering so that instead of separating, the air flows and meets up at the back of the rim. No spearation. No turbulence. Very little drag. The deeper the rim, the slower you can taper the rim which reduces the chance of separation and lowers drag.

It is still possible to accomplish this with a fairly short rim (i.e., Dura Ace 7801-SL) but it is very difficult. It's much easier to do this with a deep, wedge shaped rim like Campy Bora or Corima. But it's still not perfect. If the air is coming from the side rather than the front of the tire then you will get separation of the flow on the leeward side (at the tip of the wedge) and the drag will become quite high! This is where the Dura Ace wheel might actually be better than the Bora or Corima.

So to fight this, Zipp and Lew make the rim a bit rounded rather than a simple wedge shape. This allows the air to flow a bit better around to the leeward side before it separates, reducing the turbulence and drag. Again, the short, slightly rounded Dura Ace rim may have slightly better performance in a cross wind since it is more likely for the air to recombine without separating on the leeward side.

Zipp does some additional airflow trickery. They try to match the rim width very closely to the tire width. That way the air is less likey to separate as it makes the transition from the tire to the flat braking track. But it's still not perfect, so one of their geniuses came up with another trick. The made a bulge in the rim just after the brake track. Even though the air separates from the rim at the brake track, it hits the bulge and quickly reattaches before it can become turbulent! Brilliant.

Anyways. The general trends are that deeper rims are better and that it's better to have a tire that is appropriate for the width of your rim. These day most rims are designed for optimal performance with the common 23 mm tire size.

John Swanson
www.bikephysics.com