# Alfine 8, going low; 29x26



## pursuiter (May 28, 2008)

I spend a week riding in Jamaica on some of the hardest trails I every have ridden. I used a 32x24 on a 29'er hardtail the entire week and the hub worked/sounded/felt fine, I only wished I had a few lower gears, I really want the equivalent of a 22x36 low gear on my Moonlander. That requires a 29T front chainring and a 26T rear cog.

I ordered a pair of 26Tx1/8 cogs from Mark in MPS. When I first installed the 26T cog on an Alfine hub, I noticed the snap-ring wasn't seated correctly, It wasn't sitting in the groove.










I inspected the situation more closely and realized the 26T cog was too thick. I used my trusty ShopSmith belt sander to remove a few 0.01" until the snap-ring seated all the way in the groove.



















For the front chainring, I ordered a 29Tx1/8"x94mmx5 chainring from HomeBrewed Components, the SS forum sponsor. Now I have the equivalent of a 22x37.5 low gear and 32x18 high gear on my Moonlander. I almost never need a higher gear, and when I do it's on the road with a tailwind.

I'll be grinding on this ratio all spring/summer, it'll be interesting to see if the Alfine 8 can hold up. Please note: I'm running Mobil 1 ATF in the Alfine 8. I smear grease inside the cassette joint to prevent water intrusion. I never shift under load.


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## Drew Diller (Jan 4, 2010)

Interested also. I don't have enough long hills in MN, but I do have lots of steep "long enough" hills as I live in a river valley, my 39x24 Alfine 8 setup isn't quite low enough.


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## bikeny (Feb 26, 2004)

*Be very careful!*

I was running my Alfine 8 with a 28t x 24t combo. Unfortunately, the hub did not last for me, and now skips in 3rd and 4th gears, and maybe others. It was fun while it lasted, but I don't think the hub is able to take that much torque. Let us know how it holds up, and I will keep my fingers crossed!

Mark


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## pursuiter (May 28, 2008)

My older son (22 years old, 6-2, 220lbs) and me (same size/weight) are riding my Pugs (31x26) and Moonlander (29x26), no problems yet. We don't shift under load, it's been several weeks now. I don't think IGHs are for everyone but it appears a careful user can run very low gears on an Alfine 8 with no ill effects.


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## bikeny (Feb 26, 2004)

pursuiter said:


> My older son (22 years old, 6-2, 220lbs) and me (same size/weight) are riding my Pugs (31x26) and Moonlander (29x26), no problems yet. We don't shift under load, it's been several weeks now. I don't think IGHs are for everyone but it appears a careful user can run very low gears on an Alfine 8 with no ill effects.


I know you've been around this forum for a while, so please don't take offense, but riding them for a couple of weeks is not really a thorough test. Mine lasted about 1 year before it started skipping. Yes I was always careful to not shift under load. Maybe my terrain had somehing to do with it. I was riding Northeast technical singletrack with lots of short steep ups and downs. I think the torque generated on the steep ups, even when in a low gear, are what caused the problems. But obviously, I have no way to prove that!

Anyway, good luck to both of you, and I really do hope they last for you.

Mark


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## Agwan (Feb 16, 2011)

I am having quite a hard time understanding the ratio's on an alfine.

can I get my 11 tooth ratio? On my current cassette I tend to use the 4 smallest gears most. I want IGH but I need power more than anything.


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## Andy R (Nov 26, 2008)

Agwan said:


> I am having quite a hard time understanding the ratio's on an alfine.
> 
> can I get my 11 tooth ratio? On my current cassette I tend to use the 4 smallest gears most. I want IGH but I need power more than anything.


What ratio you have when on your 11 tooth sprocket depends on the chainring size (obviously). Assuming that it's 44 tooth, then you have a 4:1 ratio - i.e the wheel turns four times for every full crank rotation.

So, if you used an 8 speed Alfine with the same chainring (44T) in the highest gear (internal ratio 1.62:1) with an 18T sprocket on the Alfine that would give you an overall ratio of 3.96:1 which is as near as a kick in the ass to your 4:1 ratio.

Alfine 8 internal ratios are (1st to 8th) 0.53, 0.64, 0.75, 0.85, 1.0, 1.22, 1.42 and 1.62:1.

To work out overall ratios, divide the chainring size by the sprocket size and then multiply this by the hub ratio for the gear that you want to work out. 
So, if I'm using a 32T chainring and a 18T sprocket on the hub and I want to know what overall ratio 6th gear will give me then - 32/18 = 1.77 , then x 1.22 = 2.16:1.

In conventional gearing that would be like using a 15 tooth sprocket with my 32 tooth chainring (32/2.16 =14.81).


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## Agwan (Feb 16, 2011)

Okay, Fantastic! thank you!


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## Andy R (Nov 26, 2008)

You're more than welcome :thumbsup:


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## pursuiter (May 28, 2008)

bikeny said:


> ...please don't take offense...


I'm not offended, and I am not sure what your message is. The vague description of your "results" you provided doesn't make me think I need to stop or that my results will be the same. As for your discounting my results to date, you have no idea what kind riding we've subjected the hubs yet you make a point of attacking those results.

You didn't even open up your hub and take a few snaps so we could see if there's any damage. It would be interesting to try and understand what happened before you declare the hub dead. Shimano would recommend that you clean and lube the internals before you proclaimed the hub dead. In any case, it appears you are satisfied, I don't want to try and change your mind. Enjoy your derailleurs.


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## bikeny (Feb 26, 2004)

pursuiter said:


> I'm not offended, and I am not sure what your message is. The vague description of your "results" you provided doesn't make me think I need to stop or that my results will be the same. As for your discounting my results to date, you have no idea what kind riding we've subjected the hubs yet you make a point of attacking those results.
> 
> You didn't even open up your hub and take a few snaps so we could see if there's any damage. It would be interesting to try and understand what happened before you declare the hub dead. Shimano would recommend that you clean and lube the internals before you proclaimed the hub dead. In any case, it appears you are satisfied, I don't want to try and change your mind. Enjoy your derailleurs.


Unfortunately, you took my message exactly how I didn't want. I provided my results (and riding conditions) as a point of reference, that's all. Nowhere did I suggest you should stop using your hub or that your results will be the same.

I also in no way 'attacked' your results. All I said was riding the hub for a few weeks is not a thorough test, and I think that is a very fair statement.

At this point, I lack the time and motivation to open up the hub. I may do so in the future, not sure.

At this point I am happy riding my singlespeed (without derailleurs) and not having to worry about any of this stuff.

I will reiterate that I truly hope the hub works for you in the long term.

Mark


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## pursuiter (May 28, 2008)

When going low, I have found a few key points:
- The lag for a downshift to occur is longer with respect to crank rotation. I have to lighten up on the pedals for almost 1/2 crank rotation before the shift from 2 to 1 takes place.
- The downshift lag is going to be exaggerated if the lube is thick from age or cold.
- Any lag on the cassette mechanism will destroy the hub, a low friction cable routing and well geared cassette joint is critical for super low gears.
- If the hub's seals have been compromised and the hub has H2O egress, shifting will suck and all bets are off (that's why it's important to open up failed hubs).

Just adding a big cog to an Alfine isn't going to work well for long. Replacement of the stock lube with oil is critical as is lubing the cassette joint. I realize that some may think an annual service to an IGH is proof Shimano Alfines suck, I don't mind working on my bikes, I find it therapeutic. Even with all these precautions I am prepared for the Alfine to fail.

If/when the Alfine fails, I will document the actual service condition of the hub and what failed inside the hub.



bikeny said:


> I know you've been around this forum for a while, so please don't take offense, but riding them for a couple of weeks is not really a thorough test...





bikeny said:


> ... I lack the time and motivation to open up the hub. I may do so in the future, not sure...


Well, OK then...Thanks for your contributions to this thread!


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## pursuiter (May 28, 2008)

Update: I've been beating on this hub with the 29x26 on technical single track designed to IMBA standards and weekly hill climbing to the top to the local sledding hill.

- No damage climbing in 1st and 2nd gear on inclines that cause me to stall out to a stop.

- My fitness is increasing and my weight is dropping, now I'm making it to the top of the sledding hill by standing and grinding with every last ounce of power in my legs, 210lbs/6-2.

- The only drawback is the left side axle nut comes loose, I need to tighten it after every ride.

Test will continue but if my fitness continues to increase and I can make it to the top of the sledding hill in 2nd gear, I'll change to a 29x22 to help the axle nut issue.

Short review, it's hanging in there and it's fun to have a 17" gear on my Moonlander :thumbsup:


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