Schlumpf gear change - how best to adjust your cadence?

I’ve been riding my new KH/Schlumpf for a few weeks now and am still in the process of mastering gear changes. I can have a couple of dozen changes go smoothly for me and then encounter a change that feels like the wheel doesn’t engage for ages. These “long engagement” changes generally throw me off.

I think the problem may be due to changing at certain cadences. I’ve experimented and am pretty convinced that if your cadence hits a certain rate, that you can easily travel quarter to half a revolution before engaging again. This is certainly enough to throw you off if you are expecting an earlier engagement.

The question then becomes, how should you adjust your cadence when changing? Pedal faster or slower?

I suspect that if you change and then instantly accelerate your cadence, this will result in the quickest engagement.

If you decelerate hard at the moment of changing, it is actually possible to hold your cranks level while momentarily coasting along, until the wheel rotates into the engagement position. This is a very weird sensation but may not be a bad method to use either.

What works for other people? I’m keen to get to a 100% success rate on gear changes as UPDs slow me down.

the key is in where the freewheeling comes from. If you use your hands and shift up, pressing back slightly on the pedals in one direction results in immediate engagement while the other will freewheel for about a quarter rev. The same is true for shifting down except the directions are reversed. This is why shifting up is generally easier, because you tend to be putting force on the pedals forwards resulting in immediate engagement.

I know that chuck uses the decelerate method to shift down, seems to work for him :slight_smile:

I haven’t had enough time on one to learn how to shift well for myself, I just know that’s how the hub works.

I have the opposite problem. I find it really hard to shift up, but never have any trouble shifting down. With very little resistance on the low gear, it’s hard to hit the shifter button on the upshift, but it’s never a problem on the downshift.

I find shifting down tends to engage easily but I get more freewheeling when shifting up. Perhaps it depends which way you put your hub in the frame?

Apparently I run my hub around the opposite way to most people. My high gear is when the snifter button is on sticking out on the left side.

Just by the very nature of the hub, I doubt that 100% success rate is possible, but it’s certainly possible to get fairly close. I’ve now reached the stage where I hardly ever UPD, but it’s always possible, so I’m still wary about changing gear in busy traffic or anywhere that a UPD would not be favourable.

I think your observations about how the freewheel kicks in are pretty accurate. I don’t think there is much that you can do to avoid this, or predict it, but the more you shift, the more you get used to it, and the easier it is.

I will always slow down to a moderate pace before shifting. That way I’m ready for the gear to kick in strait away, or for half a rev of freewheel, or anything in between. It’ll then take one or two revolutions before I’m up to full speed on the higher gear.

Talking to Florian at RTL, though, he said some of the faster riders will kick the button, but keep pressure on the cranks for a couple of revolutions, and then when they’re ready for the gear change, just ease off for a second, ‘click’ and then they’re in high gear at a fast pace to start with. I don’t think this would work for a mere mortal like me though :smiley:


I found that the gear engaged a lot better and more consistently and predictably when I stopped using the ankle/slide method. I now twist my heel out and give the button a good kick with the inside of my shoe, instead of just tilting the inside of my foot to the button as it comes around.

Also, sometimes I do tend to sort of stop pedalling (let my feet float on the pedals) when I shift as it seems to engage better.

When I get my hub back from Florian I will try to experiment some more with shifting, but I think that a combination of either putting more force into the pedals after you shift or putting less force into the pedals after you shift will engage the gear better.

We put the gold button on the right, sticking out in low gear. So in high gear, the silver button is sticking out on the left - same as you! I think all or at least most of the local Gunis around here are setup that way.

Personally I’ve only done a couple of real rides on it and am not up to full-speed shifting yet. It’s getting better though and I was able to shift without looking down once on the first ride.


I always use the “decelerate” method, where I stop pedaling and let the wheel catch up. It works pretty reliably for me.

If you’re going to be using the stop-pedaling-and-let-the-wheel-catch-up technique, it will help sometimes to “throw” the wheel forward underneath you as you go into the freewheel; then, even at the maximum worst-case freewheeling duration, you’ll always click into the new gear almost immediately. I don’t know how else to describe the throwing of the wheel… I just jut the wheel out in front of me (sometimes quite violently!) and the wheel goes “swishCLICK!” (a process that takes maybe 1/5 of a second, maybe less if I’m trying to make it fast) and it’s engaged. The whole process is like… “chinkswishCLICK” and involves jutting the wheel about at the beginning of the “k” in the word “chink” if the chink is the button press to initiate the shift… lol. Such imprecise language!

That helps me a lot when I’m shifting up, and it makes shifting down something that I don’t even have to think about. (Shifting down is easier for me.)

I think that those of us who pause pedaling to let the wheel catch up are the ones who find it easier to shift down, and vice versa. I toyed around with both approaches (spin-cranks-really-fast, and let-it-catch-you) and found that unless I pedaled REALLY fast to catch up to the wheel, I’d end up pedaling WITH the wheel and I’d stay freewheeling for far longer than that 30 degree maximum, because I’d be always in the freewheeling state, cranks turning just fast enough to stay there. I’m to the point where I can’t even imagine shifting the spin-cranks-real-fast way…

Sorry I’m so wordy; the answer requires far fewer words than I’ve written! :slight_smile:

I talked to Bronson about this when I built my last wheel; if you build it this way, you will be properly looking at the KH signature on the hub in the “right” direction. So, this is the standard way to build it :slight_smile:


Also, read my old thread on this subject:

As others have said, the hub won’t disengage if you keep power on it; however, I don’t rely on that, and would always let up slightly right when I shifted.


Bronson :sunglasses:

Ha ha, actually it’s a different Bronson.


( bringing back this dead thread )

I learned that there is a reason, besides riding preferences, to shift from low-to-high gear with the right foot.

After losing 2 gear buttons in the last 3 months I realized that gear buttons should follow a logic similar to the pedals. When you go forward and you shift gears, the button should not “unscrew”, instead it should try to fasten itself.
And the correct position is:

  • From low-to-high: should be on the right foot

So, be careful when you shift going backwards. You might loose some gear buttons :stuck_out_tongue:

Hmm, that’s an interesting thought; should one of the buttons be reverse-threaded? It’s not getting pedaling force directly but it does have twisting forces when it’s rubbing against your foot.

makes sense to me

I did more tests this morning, and apparently my setup (from low-to-hi in left foot) doest not “unscrew” the button when I press it while going forward.

My “research” is this:

  • The button is sort of "attached" to the wheel... so it rotates in the same direction/speed as the wheel.
  • The left button rotates, when going forward, in the "unscrew" direction, but by just rotating the wheel the button is not unscrewed.
  • When I press the button I am, in a way, making the button going on the other direction... in the fasten direction
  • But my foot is also rotation, since it is on the pedal. So I might not be fasting the button.
  • Am I rotating my foot faster than my pedal ? I don't think so.

So, for the moment I don’t know the cause of why I lost 2 left buttons in 3 months.

2Nm torque for buttons

From KH Schlumpf guide:

Screw in the gearshift button about two full turns. Push the button. Screw in the button until it is flush with the crank. Install the other button on the same way. Check that there is some play underneath the button when you push it (this play allows the gear to engage if you push it a little bit more).

Use a 2.0 mm Allen wrench to firmly tighten the gear shift buttons. Use the little wrench that comes with every hub to hold the button against rotation. Check to make sure you cannot loosen the buttons by hand. If you have a torque screw driver at hand, use a torque of 2.0 Nm and you have a live (sp. life?) long warranty against lost gear shift buttons! Also available as accessory.

Important: When you push one button, its surface should be flush with the face of the crank, while on the other side, the back face of the button should be flush with the face of the other crank. When you are learning to shift, it is very tempting to make the buttons protrude further than this. Don’t do it! It is actually easier to shift if they stick out the correct amount, and they are less prone to damage or falling off.


that is how my buttons were installed. I’ve almost rubbed the gold paint off. :o I would be interested to hear your experience with getting replacements. How long did it take? I have not needed them yet (thanks to my $50 torque screwdriver) but Bronson assures me he keeps an extra set on hand stateside.