2018 Chisel 1x with SunRace CSMX8 11-speed 11-46
The stock NX 11-42 cassette works great. But on a few super steep trails, I was wishing for one more granny gear. So I finally broke down and bought a new SunRace CSMX8 11-46 cassette ($57) and installed it. Also installed a brand new KMC X11 chain ($30). Plus bought a cool tool, the Park Tool Master Link Pliers ($15) to open and close quick links.
To change the cassette, you need:
- SunRace CSMX8 11-46 cassette ($57)
- KMC X11 chain ($30)
- Park Tool Sprocket Removal / Chain Whip ($27)
- Park Tool Master Link Pliers ($15)
- Park Tool FR-5.2 Cassette Lockring Tool ($6)
- spanner wrench
Also, about an hour of time.
You might want to reference YouTube for cassette replacement.
Also, Sram has excellent quick directions here:
https://www.sram.com/sites/default/...default/files/techdocs/95-7518-006-000_rev_d_1x_mtb_derailleurs_user_manual.pdf
This PDF was super helpful for sizing the chain and tuning the derailleur.
I did NOT have to change the alignment of the derailleur. It shifted perfect. But I DID adjust the "B-Screw" to create more space between the large 46 tooth cog and the top derailleur cog (need 15 mm).
Weight & Ratio Comparision: SunRace is 73 grams lighter than NX and 150 grams lighter than eagle cassette.
Original NX (PG-1130) 11 speed cassette is 538 grams
11, 13, 15, 17, 19, 22, 25, 28, 32, 36, 42
New SunRace (CSMX8 ) 11 speed cassette is 465 grams
11, 13, 15, 18, 21, 24, 28, 32, 36, 40, 46
NX Eagle (PG-1230) 12 speed cassette is 615 grams
11, 13, 15, 17, 19, 22, 25, 28, 32, 36, 42, 50
Ratio comparison. Low/high gear ratios.
NX 11-42 with stock 30 front chainring: 0.78 / 2.99
SunRace 11-46 with stock 30 front chainring: 0.71 / 2.99
NX Eagle 11-50 with stock 32 front chainring: 0.70 / 3.19
*Note: same lowest gear ratio between SunRace and Eagle for climbing.
Why I Changed The Chain.
Initially, I used the original chain. But the derailleur looked super stretched due to the bigger large cog. I did not want to ride it that way and over pull the derailleur spring. I choose to get a new chain and resize it based on new larger cog. Added 2 inner and 2 outer links. Looks and shifts great now.
Ride Quality of SunRace.
After 2 rides, VERY happy with the new cassette. It runs very smooth with the SunRace cassette. I only needed the granny gear twice. Once on super steep "East Wall" ride with tons of lose rocks, ruts, and loose dirt. Kept slipping with old NX. Now easier to grip on steep and able to keep cadence. Second time was on a slow moving ascent up mixed rock garden with big and small boulder clusters. Other than that, the 2nd gear of SunRace is basically same as 1st gear NX. So you are just adding a granny gear. The SunRace progression through gears is well thoughtout with smooth increments.
Tested the new cassette/chain on a 13 mile ride today with 2,000 feet of climbing. Rode Alderfer/Three Sisters/Dedisse Loop. MTP project rates as intermediate (blue), although few sections of 3 Sisters are advanced (black).
New combo did great ... and bike rocked it to the top no problem.
And was a blast jumping off 6-18 inch rock and root drops and flying over gaps while racing downhill. Made all tight switchbacks up and down.
So if you are thinking about getting 12 speed eagle, consider quick fix of SunRace 11-46. SunRace is lighter and has a lower granny gear (equal to new 2019 NX eagle set up).
Not sure if I mentioned: I LOVE THIS BIKE. Specialized really made something special with the Chisel. My red rocket rips.