# Chain compatibility with an Alfine 8 sprocket



## dfuse (Feb 8, 2013)

Hi,

I will be converting my singlespeed Surly Straggler to an Alfine 8. However, if possible, I'd like to keep my front setup, CX-1 cranks with a direct mount Wolftooth narrow-wide 42t ring. The Wolftooth only takes 10-speed or higher chains. For the Alfine sprocket the Shimano website advises to use a 9-speed chain. I have been bitten before by wrong combinations of front ring and sprocket so I'd like to make sure now. 
I could replace the CX-1 with the Alfine cranks but preferably not.
Any advice?

Another question related to the gear ratio, I ride a 42x17 now. I require a bit more range both above and below that, that's why I'm going to the Alfine. What sprocket would I best use? Here it recommends to have a 19, 20 or 21 sprocket but it seems that the Alfine sprockets only exist in 18,20t. I just don't know if for example I pick an 18, how many gears do I have above and below it, ie what's the starting gear for a given combination?

Many thanks.


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## Wombat (Jan 25, 2004)

I think you'll be fine with a 10 speed chain. They are the same internal width as 8 and 9 speed chains.

For your 2nd question, 5th gear in the 8 speed hub is 1:1. This is taken from here: https://bike.shimano.com/en-EU/product/component/alfine-s7000s700/SG-S7000-8.html. If you use a 17 tooth sprocket, it will give 4 gears below and 5 above. You can use Nexus sprockets on Alfine hubs.

Gear ratio_1	527
Gear ratio_2	644
Gear ratio_3	748
Gear ratio_4	851
Gear ratio_5	1
Gear ratio_6	1223
Gear ratio_7	1419
Gear ratio_8	1615

Tim


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## dfuse (Feb 8, 2013)

Thanks a lot!!


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