Help! Stuck Schlumpf Shifter Button

[GizmoDuck]

Hurrah! I got it unstuck today, using Spencers double nut technique. I had to go to the bike shop first to borrow their ISIS crank puller. Once I got the crank off I was able to tighten the two nuts against each other, and then unscrew the stuck button on the other side.

The surprising thing is how easy it was. I hadn't actually tightened it all that hard. I think the trick is to only do the buttons up finger tight. And NEVER tighten them against each other with the Schlumpf two pronged tool on both sides. I think that's why it got stuck. I happen to have two tools because I have two Schlumpfs.

[CoreTechs]

Glad you got it all unstuck. I was getting a bit worried that you'd have to send it back to Schlumph.

[GizmoDuck]

It never ends!!!!

I just tried shifting it manually and if you don't push the shifter in far enough you get to some deadzone where the thing will freewheel constantly without engagement. Is something broken in my hub? If I push the button all the way in, it engages and that's not a problem, but if it's stuck in the half-shift zone it just spins away like a freewheel

That terrifies me. Is that normal?

[Klaas Bil]

Hurray for you for being back in business!

Originally Posted by GizmoDuck

I think the trick is to only do the buttons up finger tight.

You mean do the little screws only finger tight? Because the buttons you don't tighten at all, you adjust their position to make them flush with the crank when pushed in. They're not tight because you could screw them in further. This adjustability is needed because you never know exactly how far a crank ends up the taper (square or ISI) when tightened.

Originally Posted by GizmoDuck

And NEVER tighten them against each other with the Schlumpf two pronged tool on both sides. I think that's why it got stuck.

You should indeed never do that, but your statements makes me think you're appraoching it the wrong way. You shouldn't tighten the buttons at all. They're somewhere 'halfway' the thread. Fixing them there is done with the little screws. Read your Schlumpf instructions on how to position and tighten your buttons.

Originally Posted by GizmoDuck

I have two Schlumpfs.

Cool. How many people can say that apart from Schlumpf himself? Does anyone know?

[Klaas Bil]

It may have to do with how you adjusted (or NOT adjusted) the buttons, in that the shifter shaft can hardly go in far enough to engage the other gear because the button holds it back. There should be some play when pushed in, i.e. you must be able to push it somewhat further. It is important to get this right. My Schlumpf instructions bolden that part.

Originally Posted by GizmoDuck

It never ends!!!!

I just tried shifting it manually and if you don't push the shifter in far enough you get to some deadzone where the thing will freewheel constantly without engagement. Is something broken in my hub? If I push the button all the way in, it engages and that's not a problem, but if it's stuck in the half-shift zone it just spins away like a freewheel

That terrifies me. Is that normal?

[semach.the.monkey]

Originally Posted by GizmoDuck

Hurrah! I got it unstuck today, using Spencers double nut technique. I had to go to the bike shop first to borrow their ISIS crank puller. Once I got the crank off I was able to tighten the two nuts against each other, and then unscrew the stuck button on the other side.

The surprising thing is how easy it was.

Yay! I knew it would come good in the end

I hadn't realised that I had just expected you to have removed the other crank, so probably didn't make it clear that you needed to do that to get to the thread .

Glad it worked out. And as Klass says, check the instructions for button adjustment. Mainly by luck, mine seem to be really well positioned so they're easy to shift (when I want them to), and never shift by accident, and it's almost impossible to get to the half-shifted-freewheel stage.

STM

[tholub]

Originally Posted by GizmoDuck

It never ends!!!!

I just tried shifting it manually and if you don't push the shifter in far enough you get to some deadzone where the thing will freewheel constantly without engagement. Is something broken in my hub? If I push the button all the way in, it engages and that's not a problem, but if it's stuck in the half-shift zone it just spins away like a freewheel

That terrifies me. Is that normal?

As Klaas Bil notes, if you tighten the button too much on the shaft, it won't be able to push all the way and the hub won't function properly. I had some coasting falls when my crank got loose and pushed the button out.

Loosen the lag bolt (the 2.5mm one that you stripped), and unscrew the button until it's sitting far enough off the hub; usually, the base of the button being about level with the outside of the crank is right. Then lock the button in place with the lag screw.

The way the lag bolt and the Schlupmf slot tool work is, the tool holds the button while you tighten the lag bolt. The slot tool should be applying pressure in the opposite direction from the lag bolt; you are locking the lag bolt to the button, not locking the button to the shaft. Twist them in opposite directions until they are snug.

[joemarshall]

I only use the schlumpf tool for loosening the buttons. I just use allen key and fingers to tighten each one up so they're snug, then tighten the allen keys whilst holding the other end button still with an allen key in that. I've not had any problems with buttons, either losing them, or getting them too tight since starting to do it this way. (I've had one stuck button - put on too tight in assembly before I bought it, and one lost button - my fault for not checking).

Joe

[corbin]

Originally Posted by GizmoDuck

It never ends!!!!

I just tried shifting it manually and if you don't push the shifter in far enough you get to some deadzone where the thing will freewheel constantly without engagement. Is something broken in my hub? If I push the button all the way in, it engages and that's not a problem, but if it's stuck in the half-shift zone it just spins away like a freewheel

That terrifies me. Is that normal?

No; I ran into this same problem -- with two different hubs. The first time, it was due to failed bearings, allowing the center shaft to move and have the gears not align. The second time, it seemed due to my improper frame (hand-dremmeled bearing holders), applying uneven pressure on the bearings. It also seemed to be caused by me tightening the cranks down too tight, causing something on the shaft to catch on the the little inner lip until I hit the button again or loosened the button. The solution for RTL was to use different cranks, and to not tighten them down as much.

However, I think it should never be possible to get the hub into this state -- I think you should email Florian/Chris and let them know about the problem. I tried to detail the issue to florian when I was at RTL, but it was difficult to systematically reproduce, and we couldn't reproduce it while in a KH frame. Hopefully they can solve the issue, as freewheeling is bad!

-corbin

[osmundo]

Originally Posted by GizmoDuck

It never ends!!!!

I just tried shifting it manually and if you don't push the shifter in far enough you get to some deadzone where the thing will freewheel constantly without engagement. Is something broken in my hub? If I push the button all the way in, it engages and that's not a problem, but if it's stuck in the half-shift zone it just spins away like a freewheel

That terrifies me. Is that normal?

I had the same problem with this hub on the Triton 36er frame. I emailed KH who put me in touch with Corbin. Based on his advise, I loosened the hub and cranks a bit and added some locktight to the crank shaft. It seemed that excessive tightening of the cranks was putting some pressure on the hub. Every now and again it would just pop into the "free mode" on the downshift 1.5-1, (never the upshift). It hasn't happened since that action and I've put in several hundred miles. For a while I was really hesitant to downshift at any speed because I had some painful UPDs as a result. I hope you get the kinks worked out.

[corbin]

Originally Posted by osmundo

I had the same problem with this hub on the Triton 36er frame. I emailed KH who put me in touch with Corbin. Based on his advise, I loosened the hub and cranks a bit and added some locktight to the crank shaft. It seemed that excessive tightening of the cranks was putting some pressure on the hub. Every now and again it would just pop into the "free mode" on the downshift 1.5-1, (never the upshift). It hasn't happened since that action and I've put in several hundred miles. For a while I was really hesitant to downshift at any speed because I had some painful UPDs as a result. I hope you get the kinks worked out.

Cool; I'm glad that worked!!

-corbin

[GizmoDuck]

Originally Posted by corbin

No; I ran into this same problem -- with two different hubs. The first time, it was due to failed bearings, allowing the center shaft to move and have the gears not align. The second time, it seemed due to my improper frame (hand-dremmeled bearing holders), applying uneven pressure on the bearings. It also seemed to be caused by me tightening the cranks down too tight, causing something on the shaft to catch on the the little inner lip until I hit the button again or loosened the button. The solution for RTL was to use different cranks, and to not tighten them down as much.

However, I think it should never be possible to get the hub into this state -- I think you should email Florian/Chris and let them know about the problem. I tried to detail the issue to florian when I was at RTL, but it was difficult to systematically reproduce, and we couldn't reproduce it while in a KH frame. Hopefully they can solve the issue, as freewheeling is bad!

-corbin

I'm not sure if I have either of those problems. I don't think it's bearings because it doesn't happen all the time...only intermittently. And I don't think it's the cranks being on too tight, because they are fairly loose.

Here's a video of the problem. I'm too terrified to ride it for a 100mile race this Sunday...I took it for a spin and had a couple of freewheeling episodes when shifting. One minute you're trying to shift, next your legs are going around in circles without engagement. Funny sort of feeling.

Here's a video if anyone is interested:

[Klaas Bil]

Ken,

please check the following:

For both positions of the shifter shaft, it must be possible for the pushed-in button to be pushed in a little farther when pressed with a finger, typically a mm or so. It will spring back that same mm when released. If the button can not be pushed in farther at all, I suspect that your buttons are improperly adjusted and this may well be the root cause of your problem. I and others tried to describe this in an earlier post in this thread, to which you haven't responded (AFAIK).

[GizmoDuck]

Originally Posted by Klaas Bil

Ken,

please check the following:

For both positions of the shifter shaft, it must be possible for the pushed-in button to be pushed in a little farther when pressed with a finger, typically a mm or so. It will spring back that same mm when released. If the button can not be pushed in farther at all, I suspect that your buttons are improperly adjusted and this may well be the root cause of your problem. I and others tried to describe this in an earlier post in this thread, to which you haven't responded (AFAIK).

Oh, sorry. I think that might be the problem. But I don't want it sitting too far out...that's how I broke the last Schlumpf button, and also in case of accidental shifts. I think I'll have to add a spacer between the crank and the hub to push it out a bit. The Quax cranks are quite thin as well as straight.

Will try that tomorrow.

Cheers,

Ken

[joemarshall]

Your buttons look way into the crank. You only need a few mm of movement - you could have it further out than that without messing things up or making misshifts likely.

The correct position according to Schlumpf is roughly with the bottom of the button level with the outside of the hole in the crank when it is out, and the top of the button level when it is in. You can play around with it a bit from there, but putting it as far in as you've got it might cause problems.

The manual, including this stuff is at
http://www.schlumpf.ch/Montageanleit....engl.08.2.pdf

Putting a spacer on before the crank might not help - on the standard schlumpfs, the problem is because the back of the button sticks on the crank, however, I think on isis, you might be able to do it, as the isis axle is roughly the width of the button no? If not, then you need to use pedal extenders (little bits that attach between the pedal axle and the crank), or cranks with q-factor.

Joe