I run a schlumpf and a dingle. 33-25 (33 is the smallest ring you can run on a 110 BCD) and a 35-22. The speed drive is indeed a big jump but not at all that un-welcome, especially if you come from single speeding in the first place. I have no idea who is running around with the massive spacing of the high-speed or mountain drives, boggles my mind, although recumbent riders tend to be a little weird.
If you are looking to set one of these up I would have a couple suggestions...1. Aim low on your gears. 27 tooth (or more!) cogs might just be the money. Super spinny but nice on tech single track and the over drive is always there to bail you out when it's at all smooth. If you aim for good single-speeding gears your overdrive becomes wholly unusable. One other added bonus to the easy gearing is the cogs and chainrings will be more alike in diameter which makes slack in the dingle less of an issue. 2. Consider running a 2 tooth drop on the dingle instead of 3. I found that my 35-22 overdrive was too tall for almost anything other than a monster tail winds. If you really feel like you want to rip at 27+ mph then buy a rohloff. The 2 speed gets shifted quite a bit where the dingle is only shifted once in a while (actually wore holes in the heels of my shoes where they hit the button). Dingle almost acts to 'tune' the 2 speed shifting of the Schlumpf.
Things I like about the set-up...1. Still the lightweight (relatively speaking) of a single speed. a Rohloff puts lbs (yes pounds) of weight on the rear axle = no fun. 2. Reliable. These things have been tested to go the distance with little maintenance. No tensioners...just almost every bit as reliable as the single. 3. Sexy. Still the elegance of your single. If you forgo the schlumpf crank arms and chain rings only the most trained eye can see what's going on. Not even the cable of a Hammerschmidt. The button shifting makes it super clean. Someone had mentioned that it's hard to shift...not true. Hard at first to figure out where in your stroke to pause and kick but after a couple days (if you own one I hope you ride it more than a couple days) it's second nature.
Thing's I don't like. 1. There is some play built into the drive in the direction of the circumference of the chainrings that allows for shifting, but also allows for the chain ring to play or rattle independently of the cranks when downhilling. Probably no biggy for recumbent riders, but on tech sh#t, it's annoying. Surprisingly this doesn't seem to affect pickup at the back wheel. (no need to buy a noisy King hub with 2wice the number a pawls) Side-note: Whatever schlumpf is advertising...don't run this thing on your fixie. You'll be out a grip of cash and your tight 'fixed to the wheel' feeling will be gone. 2. Spendy as hell. Unless you're really into single-speeding already (for reasons that are beyond most) you probably wouldn't understand why buy one of these over an Alffine. If single speed riding doesn't make sense to you, $800 for 2 speeds (4 with the dingle) will seem equally ridiculous. The dingle on the other hand is a no brainer on the cost side of things. 3.My crank arms come loose but that's probably a personal problem. Also a chronic issue with square tapers.
The following was something i blogged after running Tour Divide this year with the set up...actually a snowbike with 2 non-offset 135 spaced wheels so i was actually able to carry 4 cogs (2 dingles). With a couple master links I was able to switch front to back without breaking the chain.
33-22 was the other ratio I carried in my dingle….the easiest of the 4 cogs on the bike and I didn’t change for most of the remainder of the ride. Once for a short bit in Canada but that was it. That ratio combined with the 2 speed BB planetary gear was the money. It also happened to be the easiest gear I carried…go figure.
For those of you who don’t know, a Dingle, or dingle speed, is a double-single speed bike. It basically a single speed bike that carries two gear options. The magic of the dingle is that the gears have and equal number of total teeth. That is, (in my case) 3 tooth difference in chain rings and three tooth difference in cogs so that by simply removing the rear wheel and switching the chain from one cog/chainring to the other I have another gear option, same number of teeth means no retensioning. The boys at BlackSheep are the ones that got me hooked. Does this disqualify me from the single speed catagory? YES. Most certainly.
On top of the dingle I carried two rear wheels because the bike is a snowbike with spacing in the front fork for another rear-spaced wheel. On that wheel I carried another set of 2 cogs with a 3 tooth gap between them. They were more practical single speed gears but were unused the entire ride because combined with the 1.65 rise of the 2-speed Schlumpf bottom bracket, overdrive was wholly unusable. Better cogs could certainly have been chosen.
I would say the dingles add little advantage over those running single speed bikes as I only shifted it a few times on the entire ride but the 2-speed schlumpf allowed me to run a much easier gear that would be practical had I not had overdrive to compensate on the high end. I shifted the BB hundreds of times a day. My shoes have the holes to prove it. (shifter button is on the bottom bracket spindle itself) My opinion, don’t DQ yourself on the SS catagory just to run a Dingle. The Schlumpf however, is worth it. Wheehw.
Little wordy but if your have enough of a bike-boner to be looking up running Schlumpfs with Dingles than you probably found in informative.
