# Dura ace 7900 hubs: "simple" click-adjustment



## philg123 (May 16, 2009)

You can read about this wonderfully simple method of adjusting the 7900 hubs EVERYWHERE on the internet. But you cannot find any info on what it is; where it is; or how you do it ANYWHERE on the web.

Can someone please enlighten me on how to perform this "simple click-adjustment"?

Thank you.

Phil


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## 11.4 (Mar 2, 2008)

The ends of the axles fit a pair of allen keys. Loosen them, then the cones are more or less knurled so you can grip them with fingers and turn them to adjust bearing preload. That's so you don't need to have cone wrenches. There's not a lot of magic to it. Instead of slots for cone wrenches you have some knurled surfaces so you can turn with fingers instead. If it's jammed or stuck, it's a bit of a pain. Frankly I could do anything I wanted with slotted cones anyway and rarely needed cone wrenches; if I did need the cone wrenches, it was a plus to have the slots on the cones. 

It seems that there's more shielding of the bearings in the newest design (knurled). One assumes you have a couple allen keys around, so the whole no-tools thing is a bit of a crock.

Great hubs, though. Hard to do better unless you want to go to Alchemy's hubs.


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## cmg (Oct 27, 2004)

loosen the skewers to turn the non-drive side of the hub end cap or remove the wheel. the tend cap may have a flat side or tab to grab on to. Grab and turn clockwise, if you feel contact with the bearing stop back off an 1/8 of a turn. the idea is that there should be some play when the wheel is in the frame, not more than 1-3mm when light pressure is applied. if you remove all play and adjust after contact is made then the bearings and more importantly the bearing surface inside the hub will wear quickly. while it is easy to adjust it is easier to over tighten as well.


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## philg123 (May 16, 2009)

Huge thanx for that guys. I was searching for hours on the web and got a bit frustrated (especially with lack of info on Shimano's technical docs site as well as no customer support contacts in the UK). 

Agreed 11.4, these are great hubs. They also have an elegant look to them.

thanks cmg, I now have less than 1mm of play with the wheel on the bike. Hope this isn't too little.

I'm off for a test run now. Thank you RoadBikeReview ))


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## wim (Feb 28, 2005)

*Play?*



cmg said:


> the idea is that there should be some play when the wheel is in the frame, not more than 1-3mm when light pressure is applied.


Not sure where this comes from, but am willing to listen to an explanation. Traditionally, 1 mm of play is considered excessive for a ball-and-cone hub bearing if measured at the installed hub; 3 mm would be completely unacceptable. IMO, zero play tending towards looseness should be the standard.

According to the Shimano HB-7900 / FH-7900 technical documents, the adjustment procedure for the cone is simply to, quote, "tighten the cone onto the hub axle until it has no looseness." The tech docs also state that, quote, "since the hub is unaffected by the binding pressure from the quick release, it is unnecessary to allow any play when adjusting the axle unit."

/w


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## philg123 (May 16, 2009)

That makes sense. I was led to believe that you could adjust the tightness without undoing anything. I still think that "Easy digital click bearing adjustment" is a bit misleading.

thanks for the info.


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## wim (Feb 28, 2005)

philg123 said:


> I still think that "Easy digital click bearing adjustment" is a bit misleading.


I agree. No personal experience yet, but it seems like an "indexed" type of adjustment which might not enable you to get it perfect. Kind of like those saw-tooth seatpost adjustments. But just guessing now.


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## Mike T. (Feb 3, 2004)

wim said:


> I agree. No personal experience yet, but it seems like an "indexed" type of adjustment which might not enable you to get it perfect. Kind of like those saw-tooth seatpost adjustments. But just guessing now.


Yeah I agree with your thoughts. I don't have experience with the 7900 "click to adjust hubs" (I've got lots with 8500 and other cone-wrench hubs) but have read up on the 7900 adjustment procedure. I'm down on saw-tooth seaposts (I wouldn't own one) but the 7900 hubs might be a good idea for most people. Perfect adjustment with 7900 might be possible if you hit it lucky but then I'd rather have free play rather than cones being too tight and this might make their adjustment method better, or simpler, for most people, than juggling cone wrenches.


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## wim (Feb 28, 2005)

Mike T. said:


> this might make their adjustment method better, or simpler, for most people, than juggling cone wrenches.


You're probably right. Better frequent and not-so-perfect adjustments than no adjustments at all. And truth be told, my "perfect adjustments" after a re-greasing usually are a bit out of whack after a few months anyway.


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## Mike T. (Feb 3, 2004)

wim said:


> And truth be told, my "perfect adjustments" after a re-greasing usually are a bit out of whack after a few months anyway.


I'm with ya on that one too. I'll adjust mine to the n'th degree - a gnat's whisker actually - and agonize over the adjustment for ages (without any rush) and days/weeks later I'll find too much play and have to start all over again. It beats me what the hell happened. Nothing loosened off. So maybe the 7900's quick & easy method (repeated often, as needed) is better than the more laborious cone wrench method. And it's not that I'm a cone wrench newbie.


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## BlurRoubaix (Jan 8, 2005)

*I can't seem to get my rear hub loose*



11.4 said:


> If it's jammed or stuck, it's a bit of a pain.
> It seems that there's more shielding of the bearings in the newest design (knurled). One assumes you have a couple allen keys around, so the whole no-tools thing is a bit of a crock.
> 
> Great hubs, though. Hard to do better unless you want to go to Alchemy's hubs.


I can't seem to get the little knurled nut to turn - any ideas how to loosen?


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## Pnzr (Sep 3, 2011)

BlurRoubaix said:


> I can't seem to get the little knurled nut to turn - any ideas how to loosen?


Same here, i could seem to turn the dial. Any advice?


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## valleycyclist (Nov 1, 2009)

Pnzr said:


> Same here, i could seem to turn the dial. Any advice?


On the rear hub you can remove the non-drive side end cap, slide off the black piece that locks the cone position, and then turn the cone.


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## Pnzr (Sep 3, 2011)

valleycyclist said:


> On the rear hub you can remove the non-drive side end cap, slide off the black piece that locks the cone position, and then turn the cone.


Thanks to your advice i did it with ease, i only turn it 1/8 counter clockwise of a full rotation. It starts to wobble for anything more than 1/4 turn .

Thanks again


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