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First Components Cassette Expander Cog
(8)

First Components Cassette Expander Cog

Item #: CS201Z00
USD$44.99 SAVE 36% USD$69.99 msrp
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First Components Cassette Expander Cog

First Components 10 Speed Cassette Expander Cog

Go Big!

For those of us running 1x10 setups and looking for a wider gear range out of our cassettes, First Components throws another option into the ring. This cassette expander cog will turn your Shimano 11-36 XT or XTR cassette into an 11-42 allowing for a much lower climbing gear. This is accomplished by removing the 15T and 17t cog in your cassette, installing the expander cog and the 16T where your 15T and 17T came off. First Components kindly include a longer B-limit screw to allow your derailleur clearance to enter the 42T cog. Note: A longer chain will most likely be needed post installation. Go big and KEEP PEDALING!

Features

  • Material: Anodized AL7075 (42T), Stamped Chromoly (16T)
  • Teeth: 42T (+16T)
  • Compatible with Shimano XT M771 or XTR M980 11-36T cassettes Only (will not work with SLX or Deore Cassettes)
  • Weight: 96g (42T) +23g(16T)
  • Includes longer B-limit screw.
2.9 / 5.0
8 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
1
3
1
0
3
Great addition to a 1x10.
Set up was easy. Shifting smooth so far.
September 18, 2016
Location:
Bend, OR
great value
was fast
October 27, 2016
Location:
MIAMI
Good product for the price
Delivery was on time
August 23, 2016
Location:
Winnipeg
Great innovation
Happy to change to 1x10 not so expensive
September 23, 2016
Location:
MIAMI
Works well, but must use a 1mm cassette spacer
I got this to work nicely with shimamo xt shadow +
But only after putting a 1mm spacer between this cog and the one next to it.
Cheaper than oneup which I could not get to work well.
September 28, 2016
Location:
SoCal
First component exspader cog
This cog only will fit certain hubs it will touch the spokes on many wheels and if you add a spacer then all the other cogs
Won't fit so know your type hub and spacing before you order this .
January 11, 2017
Purchased
5 months ago
Location:
Midwest
Absolute garbage
U took a chance on this and what a mistake. Paired to a new chain, cassette and chainring it skipped so bad it was unusable. Spend the extra $20 and get a wolf tooth or on one.
September 4, 2016
Location:
michigan
Doesn't fit on a Stan's Crest rear wheel
The product was delivered on time.
September 5, 2016
Location:
Seattle, WA

Q & A

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Browse 1 question Browse 1 question and 1 answer
I've been unable to mount the product, using no spacer the expander cog hits the spokes when tightened and with the spacer from the xt cassette you cannot get the lock ring on. Am I missing something? I'm going to track down a tiny spacer and see if it works but so far I am extremely unimpressed.
Ondras on Aug 31, 2016
BEST ANSWER: You need a spacer to make it work. The spacer prevents cassette from rubbing. I took mine off and ordered the wolftooth components expander cog instead i am impressed with wolf tooths drop stop chainring so id rather have matching rear.
Sent from my Verizon, Samsung Galaxy smartphone

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Free Shipping Offer

Get free Standard Shipping with your $50 purchase today! Just choose Standard Shipping during checkout.

Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items.