Riding Cambered Roads

Yeah, yesterday I rode on a cycle path which also had a lot of camber to the right, and I sat just like you and after a few hundred metres I was so twisted, I UPD’d. Since it was a one-way cyclepath, I decided to ride all the way at the top on the left at the edge, where the path was evening off. Cyclists passed me from my right without complaints. It is not often I ride with camber and won’t choose that section again.

I disagree. In my experience, it’s the other way around, round tyres are worse on camber than squarer profile tyres. I recently experimented with rim width: a large volume tyre on a skinny rim (which creates a round profile), and the same tyre on a wide rim (to create a squarer profile), and I’ve found the latter performs slightly better.

The other big factor is tyre pressure- too low pressure and the tyre becomes unrideable on camber.

My conclusion is that it has to do with tyre deformation. In order to go where you want to go, the tyre must keep the same shape. If the tyre changes shape, it will change the intended direction. If you are riding on a flat, uncambered surface, the tyre deformation is symmetrical, so it keeps going in the same direction, which is why you only notice low pressure on camber.

In terms of tyre- camber performance doesn’t correlate well with tyre profile, although I think squarer tyres work slightly better. The main factor for tyre performance is sidewall stiffness. I’ve experimented with the same tyre (Schwalbe Big One) as tubeless, as well as tubed. The tubeless required higher pressure to perform on camber, being less stiff and more prone to deformation.

GizmoDuck,
I have converted from my over simplified observation that rounder tires are better on camber and square tires are bad on camber. In one case that is true, a Coker non-skid totally round profiled tire is not effected by camber and Nightrider more square tire is quite bad on road camber. However the shape of the tire does not seem to be the whole story or maybe not any of the story. It seems to be much more complicated then that.

In this thread: New 36" tyre
OneTrackMind posted some observations and suggested that more study would be needed to better understand the issue.

Of course the other side of the whole issue is that a tire that is not effected by camber also can not make smooth turns just by leaning into the turn. And vice versa, a tire that is effected by camber can make nice smooth turns just by leaning into the turn.

Jim

Another reason I think square profile is slightly better on camber was from an experiment with my Nightrider tyre. I shaved off the side knobs (saves about 200g), but also creates a rounder profile. The tyre went from performing badly on camber, to performing even worse on camber.

I’ve not had that issue with turns.

In terms of camber it’s summed up well in the other thread, I agree that sidewall stiffness plays a part.

My idea that it is based on tyre deformation is based on:

  • tyres at low pressure perform worse on camber than the same tyre at higher pressure
  • stiffer tyres work better (eg tubeless vs same tyre tubed)
  • big volume tyres (eg Schwalbe Big Apple) are worse on camber than skinny tyres. You will find various threads where people complain about the camber performance of the Schwalbe Big Apple 2.35, but claim that the smaller Big Apple 2.0 works fine.
    Bigger volume = more air = more squishability/deformation.

In terms of tyre shape (square vs round), I think that may play a part in how stiff the tyre is, and/or the way it deforms. In my Nightrider example above, the knobs are quite hard, so there is less deformation which means the contact point with the road does not change as much.

Body position for traverses and cambered

Everybody but Todd: ignore everything that I post.

Todd:

You’re making GREAT progress.

As we’ve discussed, moving the SEAT as far over as possible against the inside leg/inner thigh will facilitate an additional few degrees of tilting the wheel over into a turn requiring less pronounced shoulder lean to compensate for balance over the center of gravity adjusted due to centrifugal turning forces (slide / slip - keeping the bubble or ball centered when flying).

Looking at your two photos, your SEAT appears to be against the outside leg/inner thigh. This requires your leg—hips—shoulder angle to become increasingly pronounced. This is a common tendency.

At least at first, you may need to mentally think your way through my preferred method (not necessarily the correct method of others) of both turning and riding traverses (camber):

  1. Put the hand on the outside of the turn (or high side of the traverse/camber) on the front seat handle (and use to control brake application if applicable).

  2. Raise up slightly, unweighting the seat.

  3. Move/slide the seat over against the leg/inner thigh of the leg on the inside of the turn (downhill side of the traverse/camber).

  4. Extend the hand/arm on the inside of the turn (downhill side of traverse/camber) as needed to maintain balance or as needed to off balance into the turn increasing turn rate (using the extended/retracted weight of your arm like an aileron).

  5. Retract your inside hand/arm back in toward your body and grip your outside hand which should still be on top of the front of the saddle gripping the handle (and controlling brake application if applicable).

As a side note this two hand placement becomes increasingly important to me as riding distance between dismounts increases. I’ll raise/lift up out of the saddle placing most or all of weight on these hands with my arms/inside of my elbows locked against my rib cage (for stability) and spin along for 40 or 50 seconds every mile at up to 120+ cadence letting fresh blood flow into my seat area parts and give seat area a short break out of the saddle.

This method of riding I perfected spinning on stationary exercise Greg LeMond trainers and unicycling on rollers a dozen years ago training for the STP.

  1. Adjust using inside arm position (downhill arm position on traverse/camber) as necessary for changing circumstances or as turn completion is reached.

I’m reposting your pictures and a recent one of me for you to compare.

Please note that my spine is close to vertical and shoulders are close to level. I’ll turn street corner and make sharp turns in this same body attitude/alignment.

Many will first claim there is no room to move their seat over. I’m a small man with narrow hips and I can. I’m only talking about a minor adjustment. Your pictures seem to reveal room for a minor adjustment. If your seat is adjusted in the wrong direction this will compound turning issues. When turning the opposite direction as the adjustment like in the picture facing the camera notice the required legs—hips—shoulder angle it requires you to make the same turn on the same camber. See how the shoulders are not level, the spine is no longer vertical, and the body is twisted.

Riding camber on a unicycle is a skill. I almost never ride anything that is truly flat. I feel sorry for anyone limiting oneself to truly flat riding—it would remove unicycling everywhere I go—sacrifice most, if not all what I enjoy about unicycling.

I learned how to ride in the steets and was making road trips before I ever learned to self mount.

As you try these body/unicycle position adjustments and if my method might work for you, I’m hopping it will open great new opportunities of enjoyment for your riding pleasure.

Continue having fun,
Joe

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I’m not as much as a camber fan as you, so I decided to ignore what you posted by not ignoring what you posted.

My ride today included plenty of odd camber situations (sometimes just steeply banked turns, sometimes off-camber turns on dirt roads while climbing/descending etc) and I paid attention to how I tackled them. I found that I more or less follow your technique, even though I haven’t really given it much thought.

So… good advice :sunglasses: .

Bungeejoe, Thanks once again for all the valuable input.

I finally got around to uploading the video that I took the couple screen shots from. It might tell more of the tale on why I fight right camber more than left.

You may very well be right. On reflection I realise that the one tyre that’s given me real problems on a cambered path also happens to be by far the lowest pressure tyre that I’ve used on-road. Strangely I hadn’t given much thought to the effect of tyre pressure.

My gut still says that a round tyre ought to be better on a camber than trying to ride on the corner of a square tyre. But I haven’t done the kind of tests that would be needed to confirm that (nor have I done anything like the kind of mileage that you have), and it certainly seems reasonable that tyre deformation would have a greater effect than tyre profile.

For what it is worth, I still find the rounder Nightrider lite way less camber sensitive than the KG, or even the former Nightrider which was more squarish.
I did not notice any issue to turn by leaning toward the inside.

My very first unicycle had a kenda nevegal 26x2.7 very squarish tire, I inflated it to its max and it was horrible, I was twisted all the time.

I think the best is thin and round, with a lot of air.

In my experience, a round tyre on a narrow rim is the less sensitive. My 29" has a Schwalbe Big One, it’s a 2.35" tire - so fairly big for a road tire. It hardly has any knobs (which is why it gets a flat per month, but that’s an other story).
I rode it for a long time on a KH 29" rim, with is what, 52mm wide if not more? It was pretty sensitive to camber. Not as bad as the Schwalbe Big Apple I had for a while, but close. When I got my new hub, I built it into a road rim, 25mm wide. It’s day and night on camber, it handles it so much better. The tire is more “pointy” and round - it actually looks smaller than when it was spread on a wide rim.

This is a bit of a side topic, but since you mention it… I have handle bars on my 32" and they car great going just forward, since my hands don’t flap about and I get bored having my hands on my back. Anyways I’ve been trying to keep my hands on the T-bar when turning, but at a 90º angle turn, I can only do it with both hands in the air. For slight bends even though I have my hands on the bar, it is my body that makes the turn, not my arms/hands.

Did you use the same tyre pressure?

My example is also with a Schwalbe Big One- using a narrow HPlusSon Archetype rim (23mm) and vs a Carbon rim (52mm). There’s not a big difference, but the carbon rim does feel more predictable and nicer to ride. I didn’t control for rim material, but the weight of the two rims are fairly similar.
I was using 50 PSI (both rims worked fine), and then I went down to 30PSI (both terrible). I rode them consecutively on the same ride (had two unicycles built up with the same setup/crank length).

Squarer tyres tend to have more tread on the side, which may lessen the tyre deformation. Oh the other hand, I’ve found round profile skinny road bike tyres (which need high PSI) excellent on camber, but they retain their shape due to high pressure (100PSI).

If a tyre changes shape, it changes the contact/friction patch, which alters the directional path of the tyre, so you have to compensate by steering. On the flat, the change is symmetrical, but it isn’t when you are riding on camber, so it wants to head off on a different vector.

Many rider report that increased tire pressure reduces the the camber effect of the Nightrider tire and others have reported no real effect. Here is my take about tire pressure on a Nightrider tire:

https://www.youtube.com/watch?v=1MPSdfdA1mU

Jim

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Great video here - JimT. And all who wrote in this thread. I’ve read it all. Forum hoover, that I am!

Going try tomorrow’s 36er ride (weather permitting) at a higher PSI than I like riding and I’ll work to deal with the bounciness in exchange for being less crooked and hanging onto the unicycle —when dealing with a super steep turning sweep of upward camber.

It’s a converted railway line and if you can picture it as one of those stretches when you can imagine that the locomotive had to put on steam to get up and round the incline. Well, I suspect that’s what was needed when it was a fully operating line. There’s a recreational steam line that follows the bike path for about 2 miles.

I can’t recall fully how I used to ride this section my my KH36 and I’m now curious how the wider 125 mm + KH spirit cranks impact camber control on my Nimbus NR set up. It’s a wider stance which I guess does make shunting the saddle / frame under one’s hips / centre of gravity more of an action than I’d have needed on the KH. But I don’t mind learning the extra muscle control here.

I’m running this wide of a set up in preparation to being “at home” with a schlumpf 125mm hub and for that I’ll run KH cranks to avoid accidental shifts.

I am curious if others find wider hubs / Q factor harder on camber sections though.

I suspect there could be a similarity with wide hubs / cranks as there is with wide verses narrow tyres and rim.

The narrow options allowing you to be more like a knife cutting through a line or your camber but requiring a lot more precision in the control.

I am certainly noticing more camber wrestling on my 36er than the other wheels I take out (G26er, BlueShift29”) :thinking:

I have found that firmly pulling up on the handle while riding tilted terrain helps to mitigate camber. Also supporting more weight on the pedals helps.

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Well I am happy to report that running 55PSI really helped a ton. I was dreading it being too bouncy or hard to manage - but it was far far more controlled, including over some of the dreaded roots and double dip ripples under tarmac I don’t like.

I rode without an angled back to cope with 95% of the camber on the stretch I ride these days.

The wheel tracked the line I needed and I didn’t need to yank it around to cope with odd off camber moments.

There is still one section where I couldn’t stay on - and that’s when the camber opens out with a downward left turn and an upward to the right curve of the path I want to stay on.

This photo doesn’t do the in real life angle of the path - it is much more slanted when you’re then and up on top of a 36er. But I sense that after a few more rides out and back I’ll nail this section.

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