Bike Build Story: Part Five, the crank. As in Part One already explained, we try to build a bike "Made in Europe". As a rule, the drive components come from the Far East. There are some exceptions with the cranks. We decided on a Tune Smart Foot.
If you look for the Smart Foot crank on the Tune homepage today, you will despair. It was the same for me and the logical consequence was to pick up the phone. I was incredulous when I heard that the production of the Smart Foot was being discontinued because they wanted to focus more on other products, such as hubs and wheels. It's a shame when a product disappears, but on the other hand we can't deny that the Smart Foot caused us problems. If you spend more than 500 euros (the recommended retail price is 599 euros without bottom bracket) for an aluminum crank, you also want it to work perfectly.
The Tune Smart Foot in detail
We ordered the Tune Smart Foot with a spider for a 76 millimeter bolt circle, which also fits Sram XX1 chainrings with a length of 175 millimeters. The bottom bracket was for BSA threads, the chainring was a 30 tooth Narrow Wide. Regarding the weight: ready for assembly, the crank weighs 592 grams with screws without bottom bracket, of which 51 grams can be traced back to the chain ring. The crank arms are made of hardened 7075 aluminum. The milling direction is parallel to the aluminum rolling direction, which is intended to replace forging the crank.
The straight crank arms and the cranked chain ring spider supposedly guarantee an undisturbed flow of power. To optimize durability, the crank has a super-smooth surface with no grids, corners or edges, which is intended to minimize the risk of breakage. The Tune Laser inscription is in a protected place, so that abrasion of the inscription and weakening of the surface by the engraving is avoided. The 30 millimeter thick axle can be accommodated in a variety of frame standards thanks to the "Smart Spindle System" and various bottom brackets. Details such as high-strength, special screws, for example to ensure the necessary preload of the clamp of the crank arm on the axle, speak for the thoughtfulness.
Light and shadow
You can feel the low weight of the crank as soon as you make contact with it. The feel of the surfaces is also convincing, as is the black anodised finish. During assembly, I was bothered by the fact that special tools were required. In my opinion, it does not necessarily have to be your own bottom bracket wrench, there are already many variants that you could have used. To mount the crank bolts you need a 17mm Allen key, not common, but at least you can order it in many places. As with almost all Orange bikes that I know, the chain line is optimal if you move the crank slightly to the left. This was also the case with Stage 6.
I decided to switch the Spider from boost to non-boost. This could also only be done with a special tool, a lot of patience and a heat gun. The assembly of the left crank arm on the axle also required a lot of effort. Also, both clamping screws had to be removed and the crank opened up by screwing in opposite directions against a coin.
Tune says: "The result is a crank with a perfect compromise between low weight and practice-oriented stiffness behavior." You can put it that way, but overall I found them just too soft. When pedaling out of the saddle or during compressions on the descent, e.g. in the berm, I thought I could feel the crank twisting under my (admittedly quite high) body weight. The final end for the Tune Smart Foot was the noise from the bottom bracket, reminiscent of a coffee grinder. After about 150 kilometers, that simply shouldn't be the case, especially since the crank is approved for all disciplines from XC to DH.
White Industries M30
So the Smart Foot had to give way and another crank came to the Orange Stage 6, which is also very popular with handmade lovers: The White Industries M30. The crank and the bearing are Made in the USA, which admittedly doesn't perfectly match our Made in Europe idea, but White Industries also does as much as possible itself and doesn't try to relocate individual work steps or even production to a low-wage country.
In terms of weight, the White Industries M30 can't quite keep up with the Tune, although it's still okay overall. We weighed: crank left 175mm 241 grams, crank right 175mm 242 grams, axle for BSA 101 grams, bottom bracket BSA 82 grams, chainring narrow-wide 28 teeth 54 grams. But assembly is child's play. It fits the same bottom bracket wrench as for example Race Face, the chainring is fixed with an old bottom bracket wrench, as required for Shimano etc. Nothing sticks, nothing pinches, everything fits very well and sits snugly. We reveal how the M30 crank finally performed in the test of the construction story.
