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wants a taco
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Discussion Starter · #1 ·
Since im not super familiar with igh's Id like to get some opinions from those who actually have some experience with them.

Im a tech at a lbs and we had a customer bring in his new (less than 20 miles) S7 hub saying he isnt getting the entire gear range and that he noticed from sram's drawings that their was this plastic locater piece missing. We call sram, they send us a new one quick, I put it in and adjust the hub according to srams directions. It shifts great in the stand but when you actually ride the bike the only way it will shift is if you stop pedaling entirely, it will not shift under even a very light load.

Once again called sram and they are sending us a new hub and we are just going to swap the internals over and send the old one back to sram.

Sounds like everything should be pretty straight forward but In talking with the customer he mentioned the bike he test rode with the same hub was doing the same not shifting unless you stop pedaling entirely and I went and rode that bike and he was right.

My main question is, do all sram S7 hubs work this way or is this just a weird coincedence. I know the alfine hubs we have do not have this problem and really it doesnt sound like something one should have to just deal with or get used to and I want to make this right but dont know how. Sram warranty is as always great but I just want to know if the new hub has the same problem if its just the nature of the beast or if I should keep bugging sram and going through hub after hub.

Thanks for any input :thumbsup:
 

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Bike Dork
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1,365 Posts
When I worked on these hubs a ton 10 years ago this was a problem when they got a lot of miles on them. Usually it was that the grease would thicken up or get gunked up and you had to pull the things apart and get ALL the grease out and lube everything with Phil's Tenacious.

That wouldn't be your problem unless it's a older NOS hub with congealed grease. It could also be caused by shifting under load causing small burrs on the edges of the gear teeth. I've found older Sram and S-A have serious problems with shifting under load that can damage the teeth.

I haven't pulled apart a Sram hub built in the last 6 years, so I could be missing something new.
 

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wants a taco
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498 Posts
Discussion Starter · #3 ·
Wow, got to say serious props to sram customer support. Got the replacement hub in and swapped the internals, same thing. So I get on the phone and talk pretty extensivly to Ed, the main internally geared hub gurus, who was a serious help. He basically told me that the s7 hub was never designed to be able to shift while pedaling and admited that sram did a bad job making that point clear in marketing and to try and keep our customer happy he sent me everything I need to convert his bike to their nice i9 hub minus rim and spokes, he is also letting us keep the old wheel all of this free of charge. I have never seen a company as good with customer support as these guys in my life and just wanted to spread some sram love.
 

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Frt Range, CO
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2,576 Posts
That's nice SRAM is punting, OTOH, the i-M9 is no walk in the park. I have an i-M9 and an Alfine. If I was in your position, I'd sell the i-M9 and buy and Alfine...my i-M9 is freezing up below 20*F. Now I need to disassemble it and clear out all the old grease and see if I can get it to work in what I would consider mild winter weather. Bought it new last summer from Harris. My Nexus/Alpine is sitting outside (Chicago) and it just works. Took it out in 0*F and shifts fine.
 

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119 Posts
I have a P5 and an S7... I say it's a minor inconvenience to stop pedalling momentarily... the shifting is otherwise flawless... Both the P5 and S7 have a solid track record for durability, so I expect to have these hubs for a long time. I do notice that I can shift and pedal on upshifts... it's the downshifts that require a hesitation in my pedal stroke.

Even the old Sturmey Archer 3-speeds seemed to have a delay in shifting... no big deal.

I have an Alfine 8-speed... it's awesome... smoothest shifting ever... Even so, despite what Shimano claims, it doesn't really shift well under load... not that a derailleur necessarily does either... I say adjust your shifting and pedalling to suit the transmission and you'll barely notice it...

BB
 

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Derailleurless
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9,122 Posts
I run an i9 on a folder and a S7 on my wife's cruiser, plus a Nexus 7 on my pavement pounder.

The S7 is a crappy shifter when downshifting, but is spring loaded and drops into gear the moment pedal pressure is reduced. Upshifts are no problem.

The Nexus is OK -- nothing to write home about, but no real problems, either. Not smooth, kind of notchy.

The i9 shifting is awesome -- smoother than my Rohloffs, in fact. I'm amazed how quiet this hub runs.

Everything I've heard about the Alfine is that it's even better shifting than the i9 (and lighter, to boot!), so I've got to make a point to ride one and judge for myself (I don't have a bike to put one on, so I won't be owning one any time soon).

It's great there are so many IGH choices, and that the industry is evolving them in a positive direction.
 

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Eff U Gee Em
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159 Posts
hey tmm

themanmonkey said:
It could also be caused by shifting under load causing small burrs on the edges of the gear teeth. I've found older Sram and S-A have serious problems with shifting under load that can damage the teeth.
I built up one of these a few years ago, and it seems like it always had this tendency to momentarily autoshift and the smallest tweak of the barrel adjuster was too much. A couple days ago I finally noticed (I rarely use this bike) that it only happened in third gear and after reading your post I'm suspecting I may have a burr on the gear. How difficult would you say it is to pull out the guts and potentially identify the "bad" gear and remedy the situation?

Thanks
 

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Bike Dork
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I don't think it's hard at all, but I've been getting paid to pull apart IGHs for 20 years. If you don't want to do it yourself and your LBS doesn't do it you can send it to Aaron's Bike Repair in Seattle and they can do it. Val Kleitz is the IG master that taught me and works there on Sundays, Aaron himself ain't no slouch either.

The problem may not be a burr. As I also stated it can be congealed grease. Flushing the hub with degreaser and then Phil's or 90-W gear oil might solve your problem without a full overhaul.
 

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MTBR Member
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In my experience, the Shimano Nexus systems tend to be more reliable. Working at a beach bike shop, I see a lot of them. Have a customer that rides a handcycle and he has been having problems with the longevity of the Sram S7 system. He typically tears them up in a couple of months. We switched him over to the Shimano Nexus7 and he has had zero issues with it. I do agree that the nexus is more clunky, but I think it holds up to heavy use better.
 

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SRAM S7 vs Shimano Nexus 7

ncfisherman said:
In my experience, the Shimano Nexus systems tend to be more reliable. Working at a beach bike shop, I see a lot of them. Have a customer that rides a handcycle and he has been having problems with the longevity of the Sram S7 system. He typically tears them up in a couple of months. We switched him over to the Shimano Nexus7 and he has had zero issues with it. I do agree that the nexus is more clunky, but I think it holds up to heavy use better.
I'd say that's a pretty credible source (not that we'd ever doubt the word of a fisherman :)
Service records don't lie, and a beach bike shop would certainly put IG hubs to the test...

I'm planning to build up an old cruiser (with an early 60s JC Higgins frame), and I am looking for a reliable IG hub with drum or roller (not coaster) brake. The Inter-7 can accept a drum, so maybe I'll give that a try... (In addition to my Alfine, which is doing extremely well handling lots of offroad abuse, but perhaps overkill for the cruiser, I already have a P5 and S7 in service, so I'm considering either a Sturmey-Archer or the Nexus).

Thanks for the great info.

Peace,
BB
 
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