Currently I am in the mood for discussing (I appreciate the “seat holding”-thread ) so I want to discuss seat heights for MU and here especially technical Downhill and technical XC.
I was used to have my seat REALLY low (knee was bent way more than 90° when the pedal was on it’s highest point) to have more leg suspension. For XC this wasn’t usable since you had absolutely no chance to ride uphill with the seat that low. But I thought it was very good for technical downhill even if I needed a lot of leg strength because I could never sit down for a few seconds (when sitting down with the seat that low it was just too exhausting to ride).
Since I am into unicycling again after my injury break I have raised the seat at about 2cm. Now it is even more suitable for XC and also on downhills I think I have improved on technical bits. That confused me because I thought more leg suspension was superior to less leg suspension.
So what are your experiences with seat hight for technical MU?
I have a hope quick release clamp on my MUni since I am ALWAYS changing seat height, depending on what I’m doing. For example, if I’m riding a steep uphill section, I always have the seat high for more power and a fuller pedal stroke. Conversely, the seat is much lower for technical stuff and hopping, jumps and all that.
Good question. As most of us know the The KH seat tube is 27.2mm I.D. But you have to order from Hope based on the Outer Diameter (O.D.) of the seat tube, since that’s how they size their clamps. The KH is approx. 32mm OD, so you would order their 31.8mm size.
That seems pretty low. I have mine set low (everyone tells me it’s low) and my leg is about 80° from the vertical.
I like a low seat post because I feel like it gives me a lower center of gravity (hence better balance and faster turning capability) and I have less far to fall during an unplanned dismount, so it feels safer. I also bend over a bit when riding so I’m lower. It doesn’t hurt my knees at all.
I understand it’s more tiring to climb hills, but I figure I’m getting a better workout that way.
I lowered my seat down about 2 inches to practice hopping in my driveway. The next time I rode, I hit the trails, forgetting I had a lower than normal seat. Within 30 seconds I could tell something was not right. I got the “I’m going to regret riding too long like this” feeling. It was hard to keep my weight on the seat and off my legs.
I was glad I had my hex wrenches with me and could raise my seat.
I need one of those clamps like Terry has. Or two. I change my seat height for the terrain. High for climbing or easy riding (though if it’s that easy I’ll use my Coker), and low for technical, steep downhill or unknown terrain.
I ran the seat very low for the Downhill race at Unicon. Even though it was technically not as hard as it might have been, less technical means faster pedaling. To ride at top speed on bumpy surfaces you need room for your legs to absorb the bumps without maxing out and either coming off the pedals or bouncing you off the seat.
I had the same thoughts when I lowered the seat. But now with the seat a bit higher it seems that I have even more control than before. Maybe because now I can hold the seat in position with my tighs too and not only with my hand.
Like mentioned before that’s interesting because it seems I have more control with the higher seat and don’t even need the suspension (Maybe because in winter technical trails are not as technical as in summer without snow). On my favourite trail I thought the seat was bouncing me off the pedals because of less suspension with a higher seat. But I found out that you can compensate that when you concentrate even more on the trail and try to “read” it.
Also thanks John, for my new sig line (from another thread)
While we are talking here it would really be interesting what’s a high or low seat for you, so if someone is bored and has time he could measure it
Having recently started using a Hope Quick Release seat post clamp, and favoring a rolling (as apposed to hoping) riding style I have definitely found it of great benefit to lower my seat for bumpy descents. A lower seat allows me to roll over much larger obstacles without being pushed off-balance by the seat as is the case with the seat at my standard height.
I have found however that a too low seat can be counterproductive, giving me a feeling of less control. On reflection I think you may be correct that this is due to the additional support provided by the thighs.
The Hope seat clamp works a treat. The saddle can twist slightly with a heavy fall but it’s so easy to correct that it’s not a problem. My saddle is up and down all the time now, it’s great!
I’m with Joe on this one- i never attack trails statically (with hops etc) and find that with my seat at a height that gives me about 2 inches of clearance when my pedal is at its lowest point suffices for all terrain. Any more clearance than that is not really useful-For any seizable drop where you need more than that 2-3 inches it is possible to rev your cranks mid air to the 3/6 o’clock position and land that way.
It seems to be a unicycle oddity that we describe seat clamp sizes with nominal measurements based on the inside diameter rather than an actual measure of the outside of the frame. So a “27.2mm clamp” means nothing without knowing the thickness of the frame tube and the paint. An aluminium frame will probably have a thicker tube than a steel one, so it can make a big difference.
It would be nice for every unicycle frame to be marketed with its seat tube O.D. and for clamps to be described the same way as bike clamps with the size of the frame, not the seat post.
Sorry - back on topic. Like Joe, I have my seat a few cms lower than for non-bumpy riding but I wouldn’t change it mid-ride.
That seems to be quite low I estimated seat clearance today while riding and with the cranks horizontal I have 4-5 inches clearance. When the pedal is at it’s lowest point there was no clearance at all. I think I could lower it about 0,5inches more but more will not be useful. I also recognized that I can pedal a lot faster with the higher seat which makes some of the steeper sections easier to ride.
I don’t know that a lower center of gravity improves balance. It’s definitely easier to balance tall things than short ones. But it does allow you to turn quicker, or in less space (less countersteer). It’s all a matter of what you’re trying to do.
I imagine it’s less bumpy if you are riding on snow. Otherwise, my idea of a low seat may be quite a bit higher than yours. I come from a Freestyle background, where we mostly rode with the same seat height (leg extension) you would use for a bike. But the faster you go on bumpy terrain, the more space you need to compensate for “surprises” along the way. My example was a race situation, where you’re going as fast as possible and taking chances. Not that this can’t be fun when it’s not a race too…
Measure what, our legs? It’s kind of like a tire pressure thing. The correct answer is not a number, unless you weigh the same, are using the same rim and tire, and riding the same way on the same type of terrain. Instead, it’s more of a thing where you have to figure out what works best for you. Clearly the higher seat is working, so maybe try it a little higher and see how that works.
I’m thinking of the difference between riding a normal unicycle and a giraffe, as an extreme example. For some people, riding a giraffe is harder (to some degree) than riding a normal unicycle. It’s easier to correct an imbalance on a shorter unicycle. People are on top of unicycles, not beneath them, when riding.
Ideal seat height would be the same on a giraffe as on a smaller unicycle. The pedals on the giraffe are raised, so that changes the center of gravity, but the seat still needs to be the same distance relative from the pedals. While the rider is on top- he controls the beneath of the unicycle through pedaling, so the height still affects the balance- with taller being slower to fall and allowing more time to react. Giraffes certainly make MU interesting- watch out for branches and roots at the same time!
I hate riding with my seat too low even for MU. Just a little bit of room for surprises is good and then I want my leg nearly straight at the bottom of the pedalstroke.
Relative center of gravity on a giraffe is much different from getting your seat height right on a MUni. Sure the center of gravity is different, but the most important thing about getting the seat height is efficient pedalling. Any MUni will have a relatively low center of gravity when it is not a giraffe, regardless of if you put your seat down a couple of inches too low. In my opinion lowering your seat an inch does not lower your center of gravity enough to make it worth squat riding everywhere. I’d rather ride at a comfortable height and sometimes be bumped off than always need to stand up in the pedals to apply power.