EB13: New Tune Blackfoot Carbon Cranks, Ultralight Aero Disc Brake Road Wheels & More

Tune-Blackfoot-carbon-fiber-crankset

Tune teased out most of their new stuff in recent months, like the wheels and crankset, but now we’ve got details and more photos. And there’s always a little surprise or two lurking in their booth (and it never hurts when the company founder is showing you around to find them!).

The Blackfoot cranks use a removable spider to run a single or double around an aluminum 30mm spindle. Weight is just 375g with their single ring, and 445g with a double, also with their rings.

The carbon panels are stitched together rather than laid into place manually, which lets them curve the sheets and hold them in place before the whole piece is wrapped around a foam core and placed in the mold. This gives them a lot of control over the layup, resulting in a very good strength to weight ratio. The arms are only about 95g each.

Tune-Blackfoot-carbon-fiber-crankset

The spindle is alloy. The went with a removable spider design because there are “too many standards floating around”, and an integrated spider would have meant limitations on chainring compatibility. When they work on the road version, it’ll have a partially integrated carbon spider, though. The spider or direct-mount single chainrings slide on and are held in place with a lockring, which is missing from this display set.

Tune-Mitochondria-single-chainring-for-mtb

The single chainring, called Mitochondria because that’s what produces energy, uses a taller tooth profile but skips the narrow/wide design. Available in 32/34/36 tooth counts. Weight is 32g for the 32t, all sold separately.

Tune-Airways-aero-carbon-road-bike-wheels

The new Airways aero rim was developed with help from a university with a wind tunnel. The goal was to get something that had minimal wind resistance and still be light, which meant keeping it from getting too deep. They ended up at 41mm, arriving at that number because they saw a dramatic drop off in resistance after 40mm.

It has a fatter, rounder shape because wind will have the same effect from any angle on a round object, and most of the wind is coming at the bike at a max 12° yaw angle. To handle braking, they infuse microscopic glass bubbles in the last layer of carbon to improve friction. They say a few may break over time, which actually improves braking, but they won’t wear off.

Tune-Airways-aero-carbon-road-bike-wheels

It’s 24mm wide (19mm inside), pushing the limit of what you can cram in standard road brakes. The spoke bed is drilled such that spokes are angled exactly toward their Mag 45/150 hubs.

What’s remarkable about all this is that it’s just 400g for the rim. And it’s a clincher. Weight is an astoundingly low 1,185g for the rim brake version.

Tune-Airways-aero-carbon-disc-brake-road-bike-wheels

The disc brake version uses basically the same rim save for an additional layer of carbon under the spoke nipples. Those weigh in at 1,260 when laced to the Princess Skyline and Prince hubs.

Tune-magnesium-steerer-tube-spacers01

Magnesium spacers are half the weight of carbon. They put a ceramic-like layer on it, then paint it to avoid corrosion. They’re available in 4mm (1g), 10mm (2.6g) and 15mm (3.9g).

Not shown, there’s a new prototype Kill Hill Brake Force One collaboration machines the living daylights out of the caliper body and lever blade. They also used alloy backed pads. The master cylinder is tiny, something they can get away with because it’s a closed system. Front is just 169g, about 10g lighter than the “regular” Kill Hill edition..

Comments

Engineer - 09/05/13 - 8:45pm

Not a grammar nazi, just helping out: “layer of ceramic like layer”

Interesting that they make carbon cranks rims ect, then make magnesium spacers at half the weight.

Speedy - 09/05/13 - 9:09pm

Engineer – my guess is that Magnesium would be a very poor choice of material for wheels and cranks. It’s much more fun to watch it burn haha.

M.A - 09/05/13 - 9:10pm

Would a magnesium wheel work? I know F1 uses it for their wheels.. However it has to due heat tolerances due to braking forces. Good question. Perhaps carbon is a bit over played?

Engineer - 09/05/13 - 9:17pm

I mean its just interesting mag vs carbon, ever seen a fork lower made out of carbon? no way. I think they have magnesium frames wheels and just about everything, they just never caught on like carbon. Im sure theres much more behind it than that, thats all I know though. I thought in the past I had looked up some information that led to almost identical weights when compared mag vs carbon, but I could not find this information again.

Tyler - 09/05/13 - 9:41pm

Magnesium has some real corrosion concerns if not properly coated, and carbon’s stiffer by weight, making it the better rim material. Also tough as nails when done right. There are some folks using carbon fiber fork lowers (DT Swiss, etc.), too.

pornitswhatlwouldratherbmaking - 09/05/13 - 11:30pm

Ooo, Tasty stuff. l’m totally in tune with these guys.

Argh - 09/06/13 - 1:13am

I do not think pure mag is used. Some kind of mag alloy.

Pmurf - 09/06/13 - 2:55am

Not a materials expert by any stretch, but here’s my $0.02: magnesium can be used in wheels, specifically rims – American classic has done this, although the availability of them has been spotty. Like @Argh said about the spacers, the mag in those rims is likely alloyed with stabilizing materials. As likely was the mag in Easton’s and ITM’s mag stems. I believe there are 2 issues with the use of mag in cycling components, one being corrosion protection, the other being its inherent temperament and how to utilize it in applications that are low risk for its failure, which might explain the lack of attempts at a mag crank.

JMS - 09/06/13 - 3:33am

@Engenieer: I have a dt swiss xrc 100 which is fully carbon (1045g for 26″ 100m) :)

I don’t like the disc brake rims…Enve dropped 60g on the rims and Tune manages to go UP?
If you don’t need the extra braking layers, how can you have a worse weight?

Like the crank tho!

Hannes - 09/06/13 - 6:25am

The founder of tune said in an interview (mtb-news.de) that the mag-spacers were born out of the drive and obsession to build something from magnesium but finding it unsuitable for most of the other parts.
He seemed overjoyed like a little kid when explaining how he finally managed to get spacers out of it.

Rohan - 09/06/13 - 6:37am

Magnesium is widely used in car rims. But it an alloy meaning it mixed with other materials like aluminum. And as correctly stated it is sensitive to corrosion and can be brittle because of it. There is however a Dutch company who makes magnesium frames http://www.segalbikes.eu/.

Mark - 09/06/13 - 9:12am

@JMS. You need to factor in the difference in weight between disc and conventional hubs. Disc hubs are heavier, usually significantly heavier. A 75 gram weight difference between the two versions isn’t all that bad. Also, even though the disc rim no longer has to cope with the compressive force of braking, it still has to resist the force applied to it by the inflated tire.

The carbon tubular disc rim may be the perfect wheel application for carbon.

DB4L - 09/06/13 - 10:17am

Any info from Tune WRT chain drop on the single? Do they reccommend a guide/tensioner or Shadow+/Type 2 RD?

Thanks.

ah - 09/06/13 - 10:54am

We dont see mag rims mainly because magnesium alloys are a pig to extrude.

eric - 09/06/13 - 1:06pm

because of magnesium’s crystal structure it can’t be rolled into sheets, which makes it pretty useless for cycling rim applications. it can be machined from billet though.

-another engineer

Jacob - 09/06/13 - 1:33pm

1,185 for a 41mm clincher! Any idea of price? That’s on my Christmas list for sure.

MMyers - 09/06/13 - 5:15pm

Many, many Dollars.

A few less Euros.

DaleC - 09/09/13 - 4:25pm

Regarding magnesium in automobile wheels – The term “mag wheel” came from makers of magnesium alloy wheels like Halibrand. My 66 Corvette had “knock off” style wheels, the ones with the big wing nut on the hub, and they were made of magnesium.

DaleC - 09/09/13 - 5:49pm

A side note on prperties og magnesium alloys, the ’65 and ’67 Vette’s had knockoffs made of aluminum. The story goes that the ’66 magnesiums were lighter and persofmed better, but were fragile. In 1986 and original set was rare enough to cost $ 3600 for a set, while original aluminum rims wnet for around $1300.

Also, if the magnesium content is high enough, you can polish the alloy and see a slight “mint green” tint. It’s how you ID correct wheels on the ’66.

Post a comment:

Comment sections can be a beautiful source of knowledge, conversation and comedy. They can also get pretty ugly, which is why we've updated our Comments Policy. If your comment isn't showing up or suddenly disappears, you might want to check it out.