Funny, but yesterday, on my KH29/Schlumpf, I switched my Ardent OUT for my Big Apple 2.0 to do a 35+ mile bike path ride. I find the Ardent harder to control on flat surfaces, and the BA much LESS squirrely. Different strokes! Anyway, just funny to hear you swapping the exact same two tires around on the exact same uni.
I ordered my Schlumpf in April, and after a couple unanswered email queries as to my order status over the last few months, it finally shipped, and arrived this morning. My LBS (United Cycle) built the wheel for my KH-29 (w T-Bar+Magura) this afternoon, and I just got back from my first ride this evening.
Wow.
I bought my first uni this last winter, a KH-24, on impulse. By the spring I had the basics down, but after years riding/racing bikes I found the 24" too slow to really go anywhere (I don’t find high-cadence pedalling appealing on any cycle). So I got a KH-29, which improved the situation quite a bit. I find the 29" at 1-1 w 150mm cranks to be just about perfect for the casual XC trails I’m interested in riding (some of the steeper hills are a bit of a challenge, but doable w practice). The 10km of paved bike paths and gravel trails to get to, and between, the trails on an average 25km ride however, are still a bit of a slog at 1-1. Schlumpf order placed.
Now, obviously, I’m still a comparative newb at this point. I mean, my free-mounting is pretty solid (but restricted to a roll-back mount), and I can roll over roots/curbs, brake down hills w the Magura, idle, and mostly ride backwards - but that’s about it at this point.
So, I figured I could start out without having to learn to switch gears with my feet, just by getting off and pushing the button and remounting. Yeah, uhh, KH-29 + high gear + rollback mount + me = FAIL. On the plus side, the Total Lack Of Movement resulting from my scrawny mass standing on the pedal seems like it could be a great way to start learning to static-mount 
Plan B. Using my heel to hit the button and shift for the first time while riding proved easier than I thought. The resulting lack of reaction from the machine given the traditional force applied to the pedals resulted in an almost instantaneous UPD. Starting with a little more speed, the fifth time was the charm. I honestly don’t know if I could have done it without the T-Bar to hold on to though.
Now, my first reaction is that it feels like someone filled the wheel with led or something. My intuition had me expecting the increased pressure required to turn the pedals, but the feeling of wheel momentum, both while starting and stopping, came as a real surprise. It feels like big heavy 43" wheel or something!
My second reaction was, WOAH ZOMG FAST! For the first time, I really wished i was wearing knee+elbow pads along with my helmet+gloves, and likely some footwear with better ankle support. Now I will stand a real chance of keeping up with casual cyclists on the bike paths, as opposed to just the joggers.
Reading here, I was worried about the amount of play/slop the gearing would introduce into the equation, and that I wouldn’t initially like the feel. I don’t know if it’s just because it’s brand new, but I barely have a millimetre or two of play in the pedals. Riding in 1-1 feels almost indistinguishable from before, aside from feeling a little heavier (due to the increased hub weight?). I did notice the slight delay of engagement during actual shifting, but when riding at speed w the T-Bar to lean on, it didn’t bother me nearly as much as I would have expected. Though that could just be due to my substantial pre-occupation with frantic pushing on the pedals while trying to keep the machine upright, and I may notice it more in the future?
The only problem I had was that I must not have torqued the one shift button in quite hard enough, because it kept rotating out, forcing me to return home (I will bring the 2mm key+tool next time).
Anyhow, just wanted to post my initial reactions, and I’m really looking forward to spending some more time on this thing now! 
Interesting…
Hey Steveyo,
That is interesting, indeed. Maybe I should switch back to the BA 2.0 and give it another go. The BA is what I started out with, and I haven’t been back since.
My rationale in going with the Ardent 2.4 was to increase the size of my footprint in order to resist twist, and to improve shock absorption. I felt like it played out that way, but maybe with a good bit more guni miles under my belt I might find the BA less squirrely than I remember. I also swear that I found it easier to climb paved paths with the Ardent in 1:1 – when it was pressured up a bit (maybe 45-50 lbs). I wonder if the fact that I am most used to riding MUni on a 24 x 3 Wildlife left me wanting more rubber on the road, and convinced it would be better?
Just curious, what pressures do you usually run in your BA & Ardent for on-road & off-road use?
Cheers,
Bert
Nice…
Hey Chris,
Yep, “WOW” pretty much describes it.
I wonder if your relatively limited amount of time in 1:1 on 1 wheel might actually help you adapt to 1:1.55 better than those of us who’ve been “stuck in 1:1” for 40 years or so?
I remember my first ride in overdrive, and how hard it was to get the blasted thing moving. A gentle downhill was essential for starting in high gear. But eventually I got to liking it – although it was not anywhere near as smooth and predictable as my 36er. Indeed, I found myself hopping off the front now and then for no apparent reason – except maybe when I came to the realization of just how fast I was going. (Fortunately with the extra height of a 29er, I almost always seem to get my feet out and under me.)
I also remember how after about an hour in overdrive on a bike path I stopped, switched back to 1:1 and could barely ride the thing. It was an absolute herky-jerky nightmare.
It’s easy to get cerebral about what is going on with learning overdrive (i.e., avoiding over-corrections that get amplified 1.55x and getting used to the play and extra inertia in the pedals), but I’m still not sure what the problem is with going back to 1:1 after an extended time in high gear.
Anybody got any insights into why it’s sometimes hard to go back to 1:1? Is it undercorrection followed by overcorrection?
At any rate, good luck with the new ride Chris, and congrats!
-Bert
Hey Bert, thanks for the bday remembrance, now if only my body wasn’t feeling so old 
Had a great birthday ride with the family, the boy and I rode muni and the ladies were on FS mountain bikes, eight miles of classes Southeast single track.
Anyway, we will be out in SLC August 18th, with free days to ride on Aug 19/20 (Fri-Sat).
I may have my 26 guni ready by then, otherwise it’ll be my tried and trusted KH 29.
I use 55 lbs or so in the BA and had probably 35-40 in the Ardent, when it’s on the guni. When I did the SingleSpeed-a-Palooza, it was on the ungeared version of the KH29, with 25-30 lbs. So they’re both pretty hard.
2011 Schlumpf hubs now with “dust guard”
I hope my master wheelbuilder does not mind me sharing this but, with my new KH36G coming soon, I am trying to stay on top of these issues so I can pull routine maintenance (a major concern of mine) when the time comes. Any insight you may provide is, as always, greatly appreciated.
To let you know, it looks like there is a potential rubbing issue on some KH frames, with the new KH/Schlumpf hub. The new hub is slightly wider with the new dust guard. As a result, there is very little gap on the inside of the bearing housing, when installed. If the weld bead at the bottom of the frame protrudes wider than the housing, it needs to be ground off to avoid rubbing. Attached is a photo showing the issue. It seems this resulted because Florian’s tester KH frames fit OK without modification, and it was not detected as a result.
Looking at the pictures (see attached) I suppose my primary concern is that the necessary modifications might effect the resale value of the frame should I ever choose to transfer my Schlumpf hub out of the 36" into say a 26" MUni frame. Will I still be able to put a normal un-geared hub into this “modified” frame or is my new frame now relegated to a “Schlumpf only” frame? Are there any other drawbacks that you can think of?
Checking.Frame.1.pdf (474 KB)
I would assume that you could return such a frame to UDC or whoever and have them replace it if you just got it new there. It is supposed to be compatible with the KH/Schlumpf hub without modification.
If your frame has been used already I wouldn’t hesitate to modify it. You could strip it too so it would be almost invisible (the modification, not the frame:) ).
And of course you could still use it for an ungeared wheel.
Have fun with your GUni!
Hey,
That’s correct, and it was a bit unforeseen.
One note: the pdf shows the entire inside face of the bearing housing ground. Really, it’s the weld bead that has a possibility to rub (e.g. if there’s any filing necessary it should be just to the weld bead).
Obviously this doesn’t help with existing frames, but moving forward, I’ll add a check to the KH frame production to make sure that the weld beads don’t extend further out than the bearing housing. Under other circumstance this hasn’t mattered so I’ve never had to do it until now. At dealers that have lots of stock it’s likely that a KH frame could be found that fit’s fine; if not it would need to be filed a bit.
Kris
stripped hex bolt
I got a bit careless today when I was changing my cranks and stripped the hex out of the secureing bolt 
Thankfully I managed to hammer a torque bit in to the hole so I could slacken it out
bummer…
Hey Alan,
Sorry to hear about your stripped bolt. I understand Florian & Kris are still trying to solve this one, but meanwhile, will be sending out a “cranksetter” bolt with the new hubs. (Correct me if I’m wrong, Kris.)
If you have yet to here of the concept of a cranksetter, you can get a description here: Schlumpf hub setup discussion thread - #71 by UPD_in_Utah
I understand from Hugo & others that you really don’t need to drill out the center of the M12 bolt, since there is sufficient clearance, but it’s not hard to do and it allows you to visually check whether the shifter rod in “in” or “out.” The main advantage is that the “standard” M12 has an 8mm hex slot, which will take the torque required to properly set/seat the crank (i.e., 40-50 Nm, or 35 ft/lbs; see page 4 of the current KH/Schlumpf manual at http://www.schlumpf.ch/hp/handbuecher/Montageanleitung.KH.engl.10.1.pdf). I used quotation marks on “standard” since it turns out that M12 bolts come in different lengths (but always the same 12mm width, with an 8mm hex slot in the head).
BTW, I routinely use a cranksetter bolt when checking crank tightness every month or so. (Like 2 days ago.) What perplexes me is why the cranks seem to loosen in the first place. (As they had since my last servicing.) Is it that the supplied hex bolt magically backs out on it’s own, or is it due to the slight wear on the cranks (in this case Moment 150mms) as they settle into their final resting place (a few years from now). Does anyone know for sure?
Best of luck,
Bert
modificaitons…
A: Yes – as explained above.
BTW: The knurled bearing cover that makes the overdrive work will necessarily “modify” your frame when the bottom bracket (bearing holder) bolts are tightened to the recommended 5-6 Nm (on that side). It forms grooves in the bearing housings on the frame! But this is normal, and critical for proper overdrive function. Plus, these “modifications” do not affect the frame’s ability to accept other wheelsets in the future, probably have zero impact on frame strength, and are inside the bearing housings, so they disappear when the bottom bracket is clamped onto the new bearing seated in the housing.
Thanks Bert
I think part of the problem has been I have been swapping cranks a lot and that constant working of the hex probably caused some fatigue… I did find the bolts loosen quite a bit…I put this down to 2 things… 1. every time you fall and the uni bouces on the road there is a high frequency vibration that will go through the whole uni causing everything to loosen…2. the contact area of the bolt head against the moment crank is tiny, I cant see any reason why it has to be so small??
[QUOTE=UPD in Utah;1470864]
Hey Alan,
Sorry to hear about your stripped bolt. I understand Florian & Kris are still trying to solve this one, but meanwhile, will be sending out a “cranksetter” bolt with the new hubs. (Correct me if I’m wrong, Kris.)
If you have yet to here of the concept of a cranksetter, you can get a description here: Schlumpf hub setup discussion thread
I understand from Hugo & others that you really don’t need to drill out the center of the M12 bolt, since there is sufficient clearance, but it’s not hard to do and it allows you to visually check whether the shifter rod in “in” or “out.” The main advantage is that the “standard” M12 has an 8mm hex slot, which will take the torque required to properly set/seat the crank (i.e., 40-50 Nm, or 35 ft/lbs; see page 4 of the current KH/Schlumpf manual at http://www.schlumpf.ch/hp/handbuecher/Montageanleitung.KH.engl.10.1.pdf). I used quotation marks on “standard” since it turns out that M12 bolts come in different lengths (but always the same 12mm width, with an 8mm hex slot in
Hi Burt
Will the bolt from another KH uni work as a crank setter?
New Schlumpf Hub
A large box arrived from Mr. Silva a few days ago. I opened it to find a nice Schlumpf hub built into a 36” wheel. I gathered the parts I had lying around my garage and assembled a 36” KH guni. It all went together well with a few torque wrenches and some care. (I am still not sure how far the buttons should protrude. Right now I can slip a paper card behind them when they are extended. I might take them in 1 mm.) I put the gold button on the right and am using 125/150 mm cranks with the pedals in the 150 holes.
I assembled the buttons with a Wiha economy torque wrench, which worked very well. It is a 2 Nm fixed torque wrench with a 2 mm hex blade for about $50 which makes the process very simple. I would recommend it:
http://www.wihatools.com/200seri/291serie.htm
The first ride was uneventful. I set it to low gear, mounted and rode around the block without any problem. I do not usually ride 150 cranks, and the tire is a bit heavier at the hub and lighter at the rim than my other 36” so the feel was slightly off, but I was easy to ride.
I switched to high gear and tried mounting. What a disaster! I usually do a rolling mount, but my pacing is all off because the cranks do not rotate with the wheel-duh!
I switched to a tire-grab mount, which got me on top of the wheel. I set off, but the tire did not and I ended up stepping off the unicycle. I repeated this comic dance several times before I gave up. The tire just does not want to move in high gear.
I regressed to an assisted mount holding onto a garbage can. Now I could get up, and starting off gently allowed me to get the tire moving. Unfortunately, my reflexes were all wrong, the tire moved too fast on my down stroke (1.5 times!) and I ended up stepping off the back. I repeated this mount several times and eventually managed to stay on for a few pedal strokes. At that point I started to get the hang of it and mounted and rode until I could ride around the block in high gear. It is much more sensitive to balance than in low gear, and I did a number of low speed UPD, most commonly stepping off the front when my attempt to accelerated failed.
The next day I rode around the block in low gear and in high gear and then tried shifting. I began in low gear with a rolling mount, and managed to shift to high gear by twisting my right ankle in until it rubbed the button. After 2-4 strokes this shifted it into high gear, and I immediately fell off. I downshifted, started again and once again managed to shift. This time I stayed on! I practiced this a few more times, mainly managing to ride through the shift.
I tried the same foot sweep to downshift and it eventually worked. I rode around the block, which includes a very small hill, and upshifted and downshifted a number of times successfully. This is a very cool unicycle!
I am shifting by positioning my heel to hit the crank. Sometimes it shifts on the first round, but more often the shift comes after a few strokes. I assume I will be able to manage it better with practice. I am shifting at very slow speed. Is this typical, or do some of you shift at high speeds? My shoe size, 10.5 (American) works fine shifting with the 150 cranks.
I am used to shorter cranks on my 36, but high gear with 150 cranks is a bit dodgy for control at this point. I basically must hold the seat so I can accelerate the unicycles out of precarious situations. I know some of you use 165 cranks for a 36 Schlumpf, and I can see why. I will stick with 150 cranks for the time being, but I am riding very cautiously.
Do you have any words of wisdom for a Schlumpf beginner?
Scott
Shifter Button Placement
Here are pictures of the shifter button positions. The silver button is too far out. I plan to move it in. Is the gold button OK, or should I move it in?
Thank you for the advice.
Scott
Scott, for ease of shifting, I recommend you keep the knobs where they are. 1mm in is just a tiny bit harder. Shifting can be smooth like butter and happen right when you think “Shift now”. It is a great feeling. I am still not at 100% but getting closer. Over the first 500 miles, progress felt slow then I got better.
Always start in low gear, even if you can mount in high gear and have to shift up right away.
When coming to a stop in high gear, get in the habit of shifting down - for practice.
Keep at it. I approached it as a new skill to learn. With over 10k miles of ungeared 36er riding experience, I was a total beginner when I got the Schlumpf. I looked at that as a good thing.
—Nathan
Scott,
You are doing well. With your progress you will soon be an expert. You might also want to check out this thread on Schlumpf Shifting Techniques:
Welcome to the club.
Geoff
I often wish I could go back to the days, starting from when i could first ride down the driveway, and experience again the joy of learning all those early, basic skills.
But short of a very “lucky” konk on the head, I can’t. I’ve learned lots of other skills in various specialty areas of unicycling, but most of those feel fairly specialized as well. Mastering the Schlumpf, especially at 36", brings me most of the way back to learning those beginner skills again. But it’s kind of better, because it’s what I consider very advanced beginning skills.
So the point is, enjoy this time, as you learn some new “beginning” skills. At first it will seem super-hard, but it will gradually get easier. The process is very rewarding, and keeps getting better for me (not counting this hiatus while I await a repaired hub). Just like learning to ride, only over a much longer period of time for most of us. 
Yes, free-mounting in high gear is also a skill, and may take a while to figure out. Generally, a 36" in high gear is a very touchy vehicle to control under 8mph or so. 10 is even better.
John, I thought for sure you would have something to say about Scott’s comments about crank length and how “he can see why some people use 165mm cranks on a 36er Schlumpf” because I took Corbin’s advice (in thread that Geoff linked to) having 9.5 shoe size and ordered the 150 cranks on my KH36G so I could “reach” the shift button. This, despite my love affair with the 165’s that I had “temporarily” put on my Impulse to prepare for the Schlumpf. Hearing Scott say the 150’s were “a bit dodgy for control” is a little worrisome. I can tell you that I loved the 150 hole on my original Impulse build and regretted the switch to 125/110’s so much (up the hills near the house) that I went full tilt got the 165’s. The good news is that I found my perfect un-geared length in the second (137mm) hole. So now, I own all three sets (165/137, 150/125, & 125/110) of KH dual hole Moment cranks. Putting the 125/110’s back on my Impulse and sticking with the 150/125’s on my KH36G as long as I can (until temptation and frustration gets the best of me and I have my LBS do the switch) hopefully without stripping the bolt (at this point, I only trust Bronson to touch my baby). More to come…