So earlier this year I installed a 42 tooth cassette cog to create an extended range setup on my 10 speed Sram cassette. It was a great upgrade to the drivetrain but I did notice very quickly that shift wasn’t as smooth across the smaller cogs. The jump from 15t to 19t was good but fair from smooth and under any kind of load was terrible. I started off with the SRAM 1070 11-32 cassette. By adding the 42 tooth cog I removed the 17 to make space. This gave me 11, 12, 13, 15, 19, 22, 25, 28, 32, 42. The 4 tooth jump between 15 and 19 was to much.
For the fair price of $14.95 plus shipping I bought the Wolf Tooth Components 16 tooth Cassette cog. Installing was super easy. After removing the rear wheel and cassette, I replaced the 15 tooth cog with the 16 tooth. Giving me 11, 12, 13, 16, 19, 22, 25, 28, 32, 42 for cogs. After reinstalling everything, first ride and putting typical shifting load through the cogs was smooth again.
In the end I suppose I shouldn’t be so surprised but the difference one cog up or down can make and the cost to sort this out is spot on. Based on the cost and the short amount of time it took to replace the cog, this is the kind of job any home bike mechanic should be doing and have on their personal to do list.
- Perfect fit on SRAM cassette
- Resolved shifting issue.
- Loss of ….. sorry can’t think of one.
Cost – $14.95
Information from Wolf Tooth Component Site below.
Shimano 10 speed cassettes
- XT 11-36t (CS-M771)
- XTR 11-36t (CS-M980)
- Other 11-36t shimano cassettes like SLX HG81 11-36t – Modification required (must drill out rivets holding the 17t to the larger cogs)
SRAM 10 speed cassettes
- PG 1030, 1050, and 1070 – 11-36 and 12-36
- X0 11-36t(XG – 1080) – Remove the 14t rather than the 17t
- See detailed instructions on our tech page: 16T instructions
- The cog is 1.6mm thick and weighs 17g
So there I am with a big grin on my face because I’m doing one the things I love, working on my bike. I had just install a new E*13 42 tooth cog, cleaned the freehub and the rear derailleur. I have decided ahead of time with this job it might be reasonable idea to install a new chain.
I had no idea how many miles was on the last one and recently shifting was less then perfect. Additionally I was upgrading from the SRAM 1031 to SRAM 1071. The biggest difference is the HollowPin saving some weight but not super light.
With the new gear setup of 32 tooth sprocket and 11-42 tooth cassette I only needed to remove a few links. Upon the removal process I notice the compound on the chain was significant. Through little research it appears to be a multitude of things. As it felt like grease the details I found called it factory oil lube. The manufacture uses a heated oil to penetrate all aspects of the chain for a few reason. Packaging, since there is no telling how long this chain will sit on the shelf waiting to start it’s life on someone’s bike the compound help moisture build up that could cause corrosion. Lube, basically primed and ready to go no additional oils or wax needed.
Dirt magnet, I wiped off as much as I could by hand. Seriously, this was like having fly paper on my bike for dirt, dust, pine needles and crunched up leaves. Logic at this point was telling me to clean this thing with degreaser or something to strip every bit of this stuff off. My drivetrain was running better and shifting well, so the combo of everything was working somehow underneath hazy powdery coating of grime. Research on cleaning/strip the chain suggested an automotive degreaser or gas. I also, found an article from Sheldon Brown. he makes some points to why it should be left on but if you feel the need to remove the factory lube he is offering a service to help.
At this point I have tried the application of wiping off the extra lube and ridding. Seriously this chain picks up everything! Keep an eye for Part 2, where I will have degreased/stripped this chain and retested whether or not it continues to be a dirt magnet.
Checkout the link to Sheldon Brown’s page.
Specifications for PC-1071 Chain
||264g / 114 links
||SRAM Force® and industry standard 10 speed systems