video? 
Glad it didn’t sink on you James.
Unfortunately, no. One of my friends was supposed to be videoing, but he got caught up saying hello to an acquaintance that happened to be walking by.
As for water in the hub: while it is certainly possible, I just added grease a day or so before, so the amount of volume not taken up by grease and gears should hopefully be quite low. That, combined with the very small time it was actually in the water leads me to think that the possibility should be quite low of any harm. Hopefully it’s the equivalent of the occasional wash.
Additionally I tried corbin’s method of shifting from a few years ago by feeling the cadence from the click of the button and then doing one hard tap. It seemed much more consistent than previous shifting efforts.
I have a noob question for the expert schlumpf riders: when shifting to high gear at average pace is it: harder ? easier ? or the same as shifting when riding slowly ?
I can nail most of my shifts up and down and the few I miss are not of big consequences. However, doing the same at a good pace may make me litterally fly (not something I am looking forward 
).
It’s hard riding slow in high gear, so it’s better if you can keep your speed up while shifting. It is a little scary. And you need to back off at least a little for the shift to click in.
I am not an expert shifter, even after 9 years riding Schlumpfs. On my 29/150mm I cruise probably at 8-10MPH in low gear, and typically slow to 6-8MPH to shift. If I miss the first attempt at a shift my speed usually drops more, and it’s quite annoying to have to re-accelerate to speed from slower than 6MPH.
I agree with tholub. It’s easier to ride in high gear with extra speed, but it’s harder to hit the button when trying to go faster. I like to switch to high gear right at the crest of a hill so gravity can make the high gear easier to turn. (Caution: I am not a talented Schlumpf rider. Better riders may give better advice.)
Max RPM in 1:1 vs Max RPM in High gear. hub issue?
Hi, yesterday I gave a first real (42km/26miles) try on the g29+ I finished to build.
Here it is :
What worries me is the gap between the max rpm I can reach in 1:1 and the max rpm I manage to pedal in high gear.
I have 137/110 cranks, pedals on the 137 holes, my max pedaling speed in 1:1 is 161 rpm which makes me go at 23.2 km/h (14.5 mph)
Yesterday I managed to reach 27.8km/h in high gear (17.375mph) which makes about 125 rpm, but found it impossible to pedal faster.
My cruising speed in high gear goes between 22 to 26 km/h (13.75 - 16.25 mph) but beyond it becomes really hard to pedal faster in high gear.
I don’t know if it comes from:
-the wind or/and air resistance.
-the tire resistance at high speed (knard 29x3 120 tpi 30 PSI)
-the wheel weight (knard : 920gm + tube : 384gm+kh freeride rim).
-the hub : gear resistance
-my technique :
…-body position : not forward enough : fear to lean too much forward and falling or the handlebar not far enough from the seat.
…-my rear leg resistance : not as relaxed as in low gear (fear and new wheel size).
-the max power I can develop (power = rpm x torque).
-a combination of several of those factors.
What I can tell is that I was experiencing about the same pedaling speed limits on the 26" version of this guni.
In the other hand, you all know this unicycle genius: nora tveit who is able at 14 to reach 35 km/h on her G29 with a max pedaling speed in high gear of 165 rpm in the 10k race at unicon 18
And even at 12 she was able to reach 30 km/h (19 mph)
ok she rides with 125mm cranks but if I am able to reach 161 rpm on the 137 in 1:1 this crank length shouldn’t be a limiting factor to pedal faster than 125 rpm in high gear, at least for few seconds, in the contrary the extra leverage should make it easier (but harder to maintain for a long period).
Ok she is lighter than me, but I’m supposed to have stronger legs if this is a power issue.
So since we are speaking about the schlumpf hub by itself, I wonder if it can come from the hub.
what is a “normal” hub rotational resistance vs a hub that doesn’t spin as easy as it should?
When I had my hub in my hands without spokes I noticed (when I was turning the bearings by hand) some kind of resistance on the two external bearings in 1:1 and also a certain resistance in high gear.
It simple doesn’t behaves like the bearings of an non geared uni.
a normal bearing turns freely with a finger pinch and continue to turn by it self a bit.
my schlumpf bearing doesn’t continue to spin when I release it.
I presume this is normal, no?
Now that the wheel is built, when I put the guni upside down the wheel doesn’t spin as freely (while letting it spinning by its own after a first crank turn) as a non geared wheel (whether I’m in 1:1 or in high gear) but it still continues to spin few wheel turns depending on the initial speed I give to it.
In fact I just made a try turning by hands the cranks, in both gears and it doesn’t seams to have a noticeable resistance, even when I start to turn the cranks very fast in high gear. at least not a resistance that could explain my speed limits.
So, what is the limiting factor? my weight? (82-83 kg), my tyre, my technique? something else?
I certainly put more often than needed this special grease syringes,(about 3 or more syringes since march), considering the viscosity of this grease could it be a limiting factor at high speed? I’m a bit skeptical about that.
What do you guys thing about all of that and what difference between max rpm in 1:1 and max rpm in high gear do you experience?
I also was a little bit surprised at first, that I’m not riding 1.5 as fast as in gear 1.
My absolute maximum speed on my 24x3.0 was once 19km/h on a road downhill. On normal road I could still reach around 16km/h. (I’m not good in pedaling fast). With my 27.5x3.0 Schlumpf I could reach only 20km/h on flat road and until now my highes speed was 23km/h on flat road.
27.5/24=1,15
1.15x1.5=1.725
16x1.725=27.6
So there are still aroun 3.5km/h missing.
What I feel is, that in second gear I still need much more of theese minimal balancing movements. So I can not leave the rear foot as weightles as in gear one.
The second thing is, it’s much easier to spin fast if there is less counterforce. Not only because of max power (power = rpm x torque). Pedaling at a certain cadence you have a defined time to rise up your pedaling force from zero to max and back to zero … every stroke. To rise up your pedaling force to a higher level within the same amount of time will not be possible, so you will reach your maximum force a few degrees later and have to start relaxing a few degrees earlier.
That’s what I believe. I don’t believe it has something to do with the hub itself. I will train to pedal in second gear as fast as I pedal now in first gear but I’m sure that when I reach this goal I also will be able to pedal faster in first gear.
A more accurate number instead of x1.5 is x17/11 which is the exact gear ratio (= 1.54545454…)
So taking your numbers :
(27.5/24)x(17/11)x16 = 28.33 km/h indeed.
Interesting reflections though, Eric, that could explain the difference , but hey, Nora even when she was 12 was still way faster than we are, and now at 14 she can reach 165 rpm in high gear, so we must miss something cause she also have to deal with those fast pedal stroke corrections.
Another thing to take in account is what tire and at what pressure do you ride your G27.5 (which is nearly a 29er at max PSI) and what crank size do you use?
But I’m sure in low gear she does not ‘only’ reach 165 but even more. I guess everybody will have a difference in maximum cadence between high and low gear. As well as everybody will have a difference between flat and down hill.
And there will allways be riders who can spin incredibly fast. As I was riding 22km/h geared on my 27.5", GreenKarl could hold up with me on his 26" ungeard. I would have never been able to coordinate my feet that fast.
The only thing we can do is to practice riding on our cadence limit as often as possible and slowly trying to expand it.
P.S. I rode very low pressure and 150mm cranks.
You shouldn’t be. Here are some additional factors to consider:
[LIST=1]
Very low pressure and 150 cranks certainly limits your speed.
On my g26+, when I had 150, in high gear I could barely reach 20km/h.
when I switched to 137 I gained about 3 to 4 km/h
- on very low PSI your G27.5+ is more a G26 than a G29 which also reduces the distance you travel during one wheel rotation + the rolling resistance becomes more important at high speed.
I guess with all the races than Nora rode during those last years she can spin even faster in 1:1, especially with 125’s.
Like I said, even if I was able to increase my pedaling speed in high gear so that I can pedal in the 150-160 rpm range, I really don’t see myself pedaling that fast during an extended period of time with the 137mm cranks.
I mean, when I do that in 1:1 I must look insane, my whole body is shaking, and the uni as well, but I guess 135 rpm could be something to work on (the 30 km/h barrier).
This.
There is no free energy. However much effort it takes to ride a certain speed in 1:1, it’s going to take 50% more to ride the same speed at 1.5:1. So if a person is riding flat out in 1:1, switching to 1.5:1 will not automatically grant them greater energy/strength reserves to go faster.
This is somewhat of a simplistic way of looking at it, and there are other factors at work, as have been noted. But I notice that as soon as I shift to high gear, the pedaling gets harder, even on level ground. And I get tired/winded quicker. Just something to consider.
I guess you should not expect keeping same rpm in high gear as in low gear for many reasons mentioned above. For me the most limiting factor is fear to crash at that speed. I don’t know my exact max as I don’t believe 36km/h showed by my GPS as current speed, but I have around 200m private test segment on Strava and I got 32,5km/h average there, which sounds reasonable with tailwind and the fact that during the marathon race I was able to keep up at least one loop after the Roger’s group who were riding around 30km/h. I was on my G27.5x3.0 when I got this 32,5km/h average, so taking wheel size from http://www.bikecalc.com/wheel_size_math it gave me 234 rpm for the wheel and including gear ratio of 1.54 it gave me crank rpm of 152, which sounds quite impressive for me in high gear. I definitely don’t dare to go above that in high gear and even that was OK in good conditions just for a short term.
I was never a fast spinner, but I haven’t measured my ungeared top this way, so it’s hard to compare, but looking at speeds I would definitely say that high gear does not give you 1.5 speed gain.
wow, that’s impressive!
what was your crank size, tyre brand and PSI and handlebars configuration?
Getting inspired by nora’s handlebars setting, and because I have used long handlebars in the past, I am working on a modification of my handlebars setting, going from this :
to this:
Yeah it’s as long as a 36er touring bar, but the idea is to keep the bar ends position (sort of) of the former config and to add another possible position (2 others indeed) much more forward/aerodynamic, but it’s not only that…:
With the first setting I encounter an issue when I break, grabbing the lever from the handlebars that are relatively far away from the saddle, and this ruins my balance, especially during steep downhills that I don’t dare to ride because of this.
It’s an issue that I didn’t have on my G26’s setting cause the break lever was close to the saddle :
G26:
So the new config that I am working on should also allow me to grab the lever from a closer hand position.
At least in theory 
My handlebar setup is quite simple as I’m using it also for muni. Currently I’m using 137mm cranks with Schwalbe Rocket Ron 3.0 tyre at unknown PSI, but rather high than low as I’m riding on the road mostly.
I also did the same segment with 31,4km/h average while on Schwalbe Super Moto X 2.8 tyre, which results in 148 rpm according to the calculations.
What might impact them a bit is the fact that Shwalbe tyres are quite often bigger than other tyres with the same size.
I’ll try to measure the exact size one day or connect a bike computer to calculate it with better accuracy.
Being the fastest G29 rider at Unicon18 I have to add something.
First of all, IMHO the maximum speed might be 1,5 (or 7/11 
) times faster than on 1:1.
Many times I feel my legs doing very high cadence with almost loosing control, similar feeling when on 1:1 ratio. I think the limit factor are skills.
There is no point to speak about any kind of resistance (rolling, bearings, gear, air) as we can counteract it by adding gravity force while riding down the slopes. Maximum speed in best conditions depends on skill, including physical and psychical factors.
If we speak about factors limiting max speed on flat surface than it shall be in following order:
- Rolling resistance - when use offroad tire the resistance is very high, and you need a lot of power to counteract, but if you change to road tire with very low resistance (for example Schwalbe Big One which is claimed to be with the lowest ever resistance) it turns like propelled itself. Feeling like on 1:1.
- Wind, air resistance is not negligible when speed over 30kmph. So it is easier to ride in peleton, and the reason why Nora did not keep up while being 15 m behind peleton.
- Rider factor. Ability to pedal fast, physical strength of muscles, psychical limits.
- Hub internal gear resistance - It exists so bring some input but very small comparing tire resistance or wind.
- Wheel weight - does not influence while the constant rotating speed is applied, but impede accelerating in either way (gaining speed or slowing down).
What is my experience from Unicon18
I did same average speed on 10km and 42km race which show that I cannot go faster in 10 km due to my ability for RPM. My legs where doing job well and I did not feel I have less power than needed to counteract any resistance. There was no psychical factor as I rode on my RPM limit with moments on the scary edge. My legs were spinning very fast and it was very difficult to keep this spinning during marathon run. On the last lap, I feel less control due to upcoming cramps. Hopefully they did not come before finish.
A quick update, (sorry for double post).
Some pics from the quick test I’ve just done on the parking :
Well, I don’t know if I will go faster but the most forward hands position is pretty comfortable!
I’ve seen myself passing by thanks to a large window and my body position was pretty similar to the position of Nora on the photo (see the post number 1981. )
The parking is pretty short so I just can start to pedal in 1:1, shift up, pedal a couple of spins and shift down before arriving at a small ramp, but even in high gear this position seemed to add a plus in term of comfort, but I’ll have to be careful of not leaning too much forward if I roll over a bump or something.
I can’t tell how it goes when riding fast for now.
In 1:1 all the way it’s clearly great, but my parking is a sort of short perfect surface for unicycling, so it doesn’t worth a real test ride.
In uphill the extra leverage given by this added length seems to make it easier too.
The “normal” position that is supposed to mimic my former bar-ends position didn’t feel exactly the same, maybe because of the added weight in front, especially during the very first pedal strokes after the freemount, but once I ride it seems ok.
Some slight adjustments may be necessary, but I’m quite satisfied with this first try.
The braking (sorry for typing “break” instead of brake sometimes) wasn’t as good as I expected in downhill but better than with the former setting.
I’ll have to get the hang of it on more or less steep downhills.
By the way the brake lever fixation is broken, a large crack appears.
So the aspect of this G29+ is a bit weird now with this gigantic handlebar in front but it seems to be worth it, at less I hope my next ride will confirm that.
Anyhow, since my G29+ is a 30er that becomes a sort of 46er in high gear, it deserves a long handlebar, right? 
Edit: vookash and makym : thanks for the input!
Makym : could you tell more about your G29 configuration during the 10k/marathon?
I use the same config for Road, XC, DH. For road racing I take Schwalbe Super Moto tire, some light tube and move pedals to 117mm holes.
From top to bottom for Muni riding:
-custom handle bar with Ergon GS1 Grip
-Hope Tech 3 lever
-KH Zero Saddle
-KH Pivotal seatpost
-Token QR seatpost clamp
-Triton frame 29
-Continental Trail King 29x2,4 tire
-Schwalbe ProCore
-Derby DH rim
-Sapim Strong spokes with Polyax nipples
-Schlumpf Hub
-KH Spirit dual hole 117,136mm cranks
-SRAM Centerline 160mm rotor
-Hope E4 Calliper with shimano adapter
-DMR Vault Superlight pedals
After Unicon I changed cranks to 110/125 and seems that I will stay with them.
Thanks for those precisions.
I like the supermoto 29x2.35 , I have it on my nimbus 29er (ungeared), and by making the choice of building my geared wheel with a kh freeride rim instead of a dominator2, I know the supermoto is not an option because this rim is known to have issues with schwalbe road tires at high PSI.
But I like the Knard tyre which is not so heavy for such a big tyre and it absorbs irregularities pretty well, even at max PSI, which a supermoto or a big one can not do at max PSI.
