Shimano Non-Series Cranks
Many newcomers and even experienced riders do not know that Shimano produces lower-priced 'non-group' cranksets. The quality and finish are optically similar with some minor technical differences to 'group cranksets'. They have been designed and produced by the same company and should work with the groupsets flawlessly at a much more competitive price...
Why non-series FC-RS500 and not series FC-R7000? Costs...
I did not opt for the modern and higher-priced Shimano 105 FC-R7000 group crankset, even though it is lighter. For me, this crank has a significant drawback: the Shimano-specific 4-arm 110 mm bolt circle diameter (BCD). In case of an exchange or replacement, you have to purchase the same specially designed chainwheels at often premium prices.
On the contrary, the non-series Shimano FC-RS500 'traditional' 5 arms/110 mm BCD pattern is tried, true, and widely available as a spare at much lower prices. To save some weight, there are even CNC-machined chainwheels available, bolts could be replaced with titanium parts.
Price Difference
While I am typing this page, the price,
- the non-group FC-RS500 costs NT$1,600 (US$ 57.44, 2021/8/10)
- the group FC-R7000 retails for NT$3,700 (US$ 132.83),
a whopping 230% (!) price difference for the pure crankset without the bb bracket!
Purchase
The FC-RS500 crankset was the first part I purchased for my 'new' old bike built. During COVID-19 it was generally not that easy to purchase scarce Shimano parts. I've used the same crankset in black on my other road bike built - ridden over several thousands of kilometers, hundreds of them with full camping gear. It performed flawlessly. When I saw the same cranks online in a silver-blueish finish, I could not help but purchase a brand-new crankset in a rare original blue Shimano box at a great price.
Technical
-Model: FC-RS500, Shimano Non-Series
-Tech: Hollowtech II Technology
-Chainring Specs: 110 BCD, 5 chain bolts
-Combination: 52/36 T
-Crankarm Length: 175 mm
-Q-Factor: 146mm
-Intended Use: Road
All 'big' manufacturers have drawings of the products they manufacture/offer available. They offer important technical data in the case of parts or modifications. Shimano stopped the link, but I've tried to post the original screenshot below:
The FC-RS500 chainwheel is available in three different chainwheel combinations:
- Compact: 50/34 chainring size
- Mid-Compact 52/36
- Standard 53/39
As my original plan was to build a better racer, the offered mid-compact (52/36) crankset came in quite handy. Compared to a compact crankset (50/34), It should increase my speed on flats while the larger 36 inner chainring would make the steeper Taiwanese hill climbs still manageable.
Weight
My scale showed a slightly higher manufacturer specification of 807 grams vs. the manufacturer's 800 g for the complete crankset incl. cranks, chainring, and bolts but without the bottom bracket.
Experience
From the aesthetics, the silver FC-RS500 looks great to me! The machined chainwheels in the 'silver-grey' raw machined finish look almost 'utilitarian' compared to modern 'sleek' parts.
The montage of modern cranksets or chainwheels are quite forward. You have to screw the outboard bottom bracket in my BSA-threaded frame, lead the chainwheel through the frame, put the crankarm on the other side of the tube, and fix it with the clamp bolts and the crankarm fixing bolt. The crankarm fixing bolt is, unfortunately, made of plastic. I later replaced it with an alloy-made part.
In the technical department, the shifting with original Shimano 105 (ST-R7000) Dual Control Levers, Ultegra FD-R8000-F front derailleur, and the 105 (RD-R7000-GS) medium caged rear derailleur worked, as expected, flawlessly. The SunRace CS RX1 rear cassette with the KMC 11-speed chain worked unnoticeably accurately - a good indication of the quality of the non-Shimano parts incl. the non-series crankset.
Conclusion
For sure, there are higher graded, lighter, and much more expensive cranksets out there, but the original FC-RS500 as part of my Shimano 11-speed setup makes the FC-RS500 crankset not only a breeze to install but it also works smooth and reliably after thousands of kilometers.
Shorts
+plus:
+reasonable priced
+ available in various chainrings and crank lengths
+ reasonable weight
+ good shifting
+ widely available 110/5 BCD chainrings, good looks
-minus:
- the plastic crank arm fixing bolt
Ride carefully, Gerhard
A Word of Caution
Always ride with a helmet and in a way that you are in control of the bike and not the other way around. Ride responsibly and defensively, and be prepared for a worst-case scenario! It is senseless to gain some seconds but spends weeks to recover in a hospital and/or at home for a stupid action!
You, your body, your parents, your family, and your friends will surely appreciate your precautions before, during, and after a bike ride.
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