Geared Coker thoughts...

I am a 50/50 Coker/technical Muni rider (36 and 24) and like them both equally.

I ride a 36er with 125mm cranks and can cruise around at 13mph all day long and do some moderate technical terrain with it too (up stairs, small drops, etc.)

I bought a Schlumpf Coker a few months ago thinking it would bring a whole new world of big wheel riding but I am still not feeling it.
It seems like the standard Guni Coker setup is longer cranks which bring the gear ratio down then add the Schlumpf which brings the ratio back up. It seems to me the net benefit of this is about a 15-20% higher speed in high gear and maybe a 30% advantage in the 1:1 gear. (It is a myth about doing insane speeds – Unless of course, you keep very short cranks on there…).

There is the complication of actually changing gears on the fly too and loss of dexterity. On my fixed Coker, you can navigate crowds easily by stopping and hopping and still standing till you have an opportunity, then riding off again. This is very hard to do in high gear on a 36” wheel. I can see the geared Coker would be an awesome machine on the very long distance all-flat-terrain riding but that does not happen much in the real world.

Anyway, I am inclined to buy a KH26 Muni and swap hubs so I will have a multi-purpose super machine that can go as fast as my Coker and also drop some trails too. It seems like that would be a far more useful uni. I have riden 24” and 29” Gunis and find that it gets much harder as the wheel size goes up.

I am posting this in case I am missing something about the virtues of the Guni Coker and someone can educate me before I go to that expense. I can always switch back of course. I would keep both.

Any input appreciated. Thanks…

650b? :smiley:

Seriously though, since you already have the schlumpf, I’d definitely throw it in a smaller wheel. With the current step, a 26 would be a great wheel size for it. If we can ever get the mythical 1.33:1 step (don’t hit me guys), a 29er would be the cat’s PJ’s.

Unless a downgear became available (which will never happen), I wouldn’t put a schlumpf in a 36er.


If you have ridden a G24, G29, and G36 I think you have a pretty good idea of how a G26 will feel.

I have a G26 and love it, even though it is geared a bit higher than a 36 in high gear I don’t quite get the same average speeds, though it is close. I have yet to try a geared 36.

Catastrophic failure

Thanks Saskatchewanian (and Killian)
I actually used your gear ratio charts to formulate my thoughts - Very helpful.

I am not a superstitious person but I think my blasphemous thoughts may have angered the Guni Gods…
I was out riding the Guni Coker today - and going at top speed - when the cranks became spontaneously disengaged from the wheel and I slapped down HARD. Two bloody knees, one bloody elbow and two sore palms. I am surprised I did not break anything.

I can literally free-spin the cranks now while the uni is standing still - I am sure that should not happen.
I need to do some reverse engineering here but I think this would be fall under the category of ‘catastrophic failure’.


What serial number is your hub? I am wondering if it was one of the ones that was recalled back in 2008.

I strongly suggest you call up Florian and explain what happened. He would probably want to have a look at your hub.