Going 1x10 - what to buy

The key to getting the best out of your 1 x 10 setup is to have the right mix of components. Everything is a compromise and going 1 x 10 is no exception.

Three key ingredients

• Clutch rear derailleur
• Narrow-wide chainring
• Wide ratio cassette

How much will going 1 x 10 cost?

The cheapest setup will be around $200:

The most expensive will be almost double the least expensive and it mostly comes down to the rear derailleur cost:

What rear derailleur cage length?

A medium cage (eg. Shimano GS or SRAM equivalent) rear derailleur will work with an 11-42t rear spread.  On some bikes, a short cage (like the Shimano Zee WR version) will work with an 11-40t or even 11-42t spread.   If you've got a full suspension bike with any amount of chain growth through suspension travel, then go with a medium cage rear derailleur.

Additional items

To get the most out of going 1 x 10 you may need some additional items:

16t cassette cog

Adding an extra cog to your cassette involves removing another to keep the total cog count at 10. Normally on 11-36t cassettes the 15t or 17t is removed resulting in a big gap. To get a more consistent change in range you can remove both the 15t and 17t and replace them with a 16t. Some cassettes have a 16t so you may be able to get one from there. 16t sprockets are available from:

• OneUp;
• Wolftooth;
• cassette manufacturers like Miche; and
• Shimano.

If using a Shimano 16t then choose the 9 speed version as it will have the shift points in a position that will work better with the gap in the cassette. 

Rad cage

Shifting into and out of the 42t cog on the cassette can be compromised when using Shimano rear derailleurs. A possible solution is to use the OneUp RAD cage. It offsets the top jockey wheel so that you require less tension on the b-screw for the top jockey wheel to clear the extended range sprocket. 

Note: the RAD cage is only applicable to Shimano rear derailleurs.  The SRAM clutch rear derailleurs already have an offset top jockey wheel.

Problem solving

Issue: slow shifting into/out of the 40/42t cog

Solution: make sure your extension cog is properly aligned and that it is the right type for the particular cassette you are using.

• OneUp components 40t and 42t sprockets have two different installation positions depending on whether you are using it with a Shimano or SRAM 11-36t cassette.  It does not appear compatible with Shimano 10 speed 11-34t cassettes;
• Wolftooth Components makes two different versions of their 40t and 42t cogs for use with either Shimano or SRAM 11-36t cassettes.  Make sure you are using the right one;
• e*thirteen 42t extended range cogs, like the Wolftooth Components versions come in two different versions depending on whether you have a Shimano or SRAM 11-36t cassette. e*thirteen also produce a 40t extended range cog which is specially made to work with Shimano 11-34t cassettes.

Issue: lack of b-screw adjustment

Solutions:

• longer b-screw;
• reverse existing b-screw to make it longer;
• install OneUp RAD cage (only applicable to Shimano rear derailleur setups).

Issue: chain too tight in 40t/42t and too slack in 11t

Solution: Shimano rear derailleur? Check the orientation of your axle bracket unit and make sure it is near to horizontal - see here for some pictures of a Zee RD with the axle bracket unit properly oriented are you using a short cage rear derailleur?  If so, you

Issue: derailleur inner cage interferes with 40/42t cog

Solution: try adding more b-tension with b-screw.  If this doesn't work, then chain is too short - add links back in until it clears properly.  If using a short cage rear derailleur, then check that chain is now not too slack in 11t.  If it is, then swap to medium cage rear derailleur.

How does this compare to 1 x 11 systems?

Gear range

SRAM currently offer two 11 speed MTB groupsets: XX1 and X01.  These systems both have a 420% gear rage spread from 10-42t. At best your diy 1 x 10 will have a slightly narrower spread of 11-42 effectively losing 10% of range on the top end.

The new Shimano 11 speed system has an 11-40t cassette, so your DIY system with an 11-42t offers slightly more gear range than a XTR 1 x 11 speed setup.  The benefits of the Shimano system are that a new freehub is not required.  The cassette fits on a standard freehub.

Cost

XX1

X01 

Shimano 1 x 11 cost