I volunteer at an inclusive cycling group. They have a wheelchair bike with Sturmey Archer / SRAM S7 hub gear. The Clickbox is loose so the trike is stuck in first gear. The thumbscrew is screwed in tight but the clickbox doesn't grip. Any ideas please.

is there an extra washer or a different axle nut in use?
those bell cranks are pretty basic units... i'm assuming "Click Box" is what someone has chosen to call the bell crank...

sounds like the thumbscrew isn't catching the end of the axle.

fender mount on axle?
extra washer/s?
a torque washer on the wrong end of the axle, maybe?
an oddball axle nut?
poorly re-centered axle after a rebuild or servicing?

shimano bell cranks attach to the axle nut, and positively locate via a 12 point spline .... a better setup.

Thanks for suggestions - will check these out

The S7 click box is considerably more complex than a simple bell crank.
To the OP. Are you sure you have all the parts? There should be a red plastic locating tab that correctly orients the outer shift sleeve.
If you are not sure what I mean, I can dig one out later when I get home and post a photo

yet another reason i avoid things branded as SRAM...

there seems to be a red plastic part that clips over the axle end, as Dan asked about... if it's missing, it probably broke and must be replaced.
contact a SRAM dealer with any info you can find on your hub.. there are a couple differing models with the same basic name.
good luck.

i've worked on dozens of other enclosed gear hubs/shifters... they use a simple bell crank design at the axle, or the classic rod and tiny chain, ala sturmey archer.... apparently, SRAM felt some need to re-engineer the wheel... again.

This is what it should look like when properly installed.

When the clickbox is removed, there should be a red locating sleeve on the axle.

There should be a rod and an outer sleeve protruding from the axle. The inner tab of the red plastic locating sleeve engages with the slot in the shift sleeve to properly orient the fingers in the click box to engage the shift rod and sleeve.


If any of these parts are missing or broken, the click box will not work.

Many thanks for your help - this is really useful. I'm due back in next tuesday and will take another look and compare photos. Yes it does have the red plastic sleeve which locates OK. It looks like there's a groove that the thumbscrew should go into but for some reason the assembly isn't pushing on far enough for the thumbscrew to reach the groove. Or else the end of the screw is somehow broken off. I'll let you know how I get on.

The idea is to allow the wheel to be removed and replaced or the chain to be adjusted without having to adjust the gear cable every time. Also the indexing is in the clickbox rather than the shifter. I'm pretty sure it pre-dates SRAM's ownership of Sachs.

i guess you missed the SRAM name splashed on the parts, huh?
the design was revised after SRAM bought sachs.

PS, the bell cranks found on Shimano IGH systems don't require re-adjustments after removal/re-installs.... they shoulder onto the end of the axle....

the S7 hubs are fairly common in Europe... they've received limited use in the USA.
the vids online are mostly not in english....

most of the bikes i saw fitted with S7 hubs feature a "roll cage" for the click boxes, similar to the ones the box store bikes use to protect the tourney derailleurs... the click box hangs too far out, in harm's way.

i'll be advising Not using a clickbox hub.

i bet those red plastic pieces snap easily when they get older...

Ensure the shifter is in the first gear position before trying to install the click box.
If it resists going all the way on, you may have to turn the input sprocket a little bit to allow the rod and sleeve to push into the axle.

The S 7 was inherited from Sachs, as were the 3 and 5 speed hubs.
You are incorrect about the indexing. It is in the shifter, not the click box.
Rohloff hubs are indexed in the hub.

dan.. do you happen to know who owned Sachs when the latest, updated clickbox was introduced?

Servicing a Clickbox... and it shows MOST of the cable replacement too.. except PRE-Setting the cable length, Disassembly/reassembly of the Twist shifter (The tube Clicks into the body, and holds the whole thing together, Remove the Bar clamp to access the tabs), etc...... !
Remember to wind the cable TWICE.around the clickbox bellcrank,,,, Err, "Reel"..

https://www.bing.com/videos/rivervie...BC81C9B7762202

I don't really know the answer to that question. I am aware of three versions, but who actually developed the newest one I can't say for sure.
Sram acquired the gearhub business from Sachs in 1997, but production under the Sachs name continued for a couple of years I believe.

The need for an exacto knife and glue is a pretty good clue that it was not intended for that level of disassembly.
Shift cable replacement is not too difficult as shown here.

But did not originate at SRAM, hence my comment.

Ah thanks, I misremembered, I've maybe dealt with those a couple of times, a long time ago.

All fitted and working well now. Thanks again for your help

was something misaligned?
this tread will help others in the future.
anything you found may become the answer for dozens of folks.
glad it's working for you!

For some reason the clickbox wouldn't seat properly but after judicious wiggling a reassuring click was heard and I was able to push it home and tighten the thumbscrew into its groove.