# turns on steep terrain



## KeithNorCal (Jun 7, 2016)

Okay, climbing turns versus switchbacks versus insloped (bermed) turns. These are basically the terms used in Trail Solutions: IMBA's Guide to Building Sweet Singletrack. I'm currently working on a trail on my own property. It's just about 5 acres and I'm hoping to get a loop that is about 3/4 mile with about 200 feet of climbing per lap. It's pretty steep terrain. I'm just working on the first section now, which seems to have a fall-line of about 20% grade on average. The trail has to descend that slope and then climb back up, but I want to be able to ride it in both directions for variety and I'm mostly a single-speeder so I'm trying to keep the grades pretty moderate. IMBA recommends only using "climbing turns" on slopes that are 7% grade or less, meaning that the vast majority of my turns will have to be either switchbacks or insloped (bermed) turns. Switchbacks have the advantages of being able to create turns in very tight areas and on very steep slopes, but they slow the flow of course. Insloped (bermed) turns require a greater turning radius than switchbacks but I'm not a huge fan of bermed turns just because they look particularly unnatural to me unless they somehow incorporate the natural topography. For reasons I can't explain, I find wooden bermed turns more visually appealing than high earthen bermed turns. I'll probably have to build switchbacks in some places but want to minimize them for the purposes of flow. For now I guess I just have a couple of questions about insloped (bermed) turns. For a bi-directional trail, what is the steepest fall-line on which you would recommend building a bermed turn? What is the minimum radius you'd recommend for a bermed turn? Thanks!


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## Cotharyus (Jun 21, 2012)

You should look up Switch-berms.


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## eb1888 (Jan 27, 2012)

I've read the IMBA manual(interlibrary request) and watched the dvd and I wasn't impressed...with the techniques presented for building challenging fun singletrack. That info appears vetted by lawyers. Aimed at flow for getting from one point to another, not about the journey. You're building a loop, not getting to the next town.
The turn construction segment has some basics and just stops. You'll have to move past what they offer so as not to sanitize your terrain too much, imo.
Managing the water is primary in getting technical features worked into slopes. If you can copy a tech feature from a trail you like I'd use that as a foundation and skip the 'manual'. 20% grade is a valuable resource but is near 12* angle. 20* angle is a 36.4% grade. IMBAs 7% grade is a 4* angle. Who wants to ride that.


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## Harryman (Jun 14, 2011)

There's a lot of "depends" in the answer to your question. You can build any sort of turn on any sidehill if you're willing to pay the price in constructing it. I've seen really nice bermed turns built on very steep side hill using what I call Omega turns, where the two legs are close together, necessitated by the steepness, but the turn itself is built into and out onto a turning platform. It's shaped like an Omega fwiw. You need to move a lot of dirt to do it though, a consideration if you have to do all the work yourself and by hand.

This is the shape, although this is pretty flat obviously and the ones I'm talking about had a smaller radius, 4-6 ft maybe. Still big enough to easily roll through.









Since it's on your property, you don't have to worry about a ton of traffic screwing things up, which opens up possibilities on the design side for being able to push the envelope of sustainablility.


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## KeithNorCal (Jun 7, 2016)

Harryman said:


> Since it's on your property, you don't have to worry about a ton of traffic screwing things up, which opens up possibilities on the design side for being able to push the envelope of sustainablility.


Very true regarding minimal traffic, and you make good points about moving dirt by hand too (which I have to). Once the trail is built I don't want to have to frequently repair water damage, so proper drainage is the biggest sustainability issue I'm trying to plan for. For example, I'm trying to incorporate grade reversals into every turn.


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## cmc4130 (Jan 30, 2008)

https://forums.mtbr.com/trail-building-advocacy/bermed-corner-photos-381772-2.html#post8141387


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## feral (Feb 10, 2007)

Have you measured your side slope with a clino to verify your 20% slope? If not, get a clino (and a friend) and figure out what it actually is - that's important and good data to collect.

Next, I would second the bermed turns for your loop. Much less work than creating switchbacks with climbing platforms and a lot more fun to ride. Plus you can ride them in both directions: going up hill you'll just be down towards the inner side of the berms. The diagram posted above by cmc4130 is good from an instructional view, importantly noting the drainage outlets. For esthetics (since you noted you weren't keen on how berms look), you could use plantings to mask the berms - but also note that the berm walls don't necessarily have to be giant: they might only be 18"-24". Also, you can minimize the size of the berms if you locate them in spots where the slope is slightly less.

For most permanence, use rocks for the core of the berms, not logs. Those will decompose. And build the berm up in "lifts": bottom layer, add fill, compact, add more, compact, repeat. Sculpt and compact.

Sounds like a fun project!


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## KeithNorCal (Jun 7, 2016)

feral said:


> Have you measured your side slope with a clino to verify your 20% slope? If not, get a clino (and a friend) and figure out what it actually is - that's important and good data to collect.


Yes, measured with a clinometer.  I measured the fall line at the diameter of every turn that I flagged and they range from 17% - 23%. I also measured the slope of all of the interconnecting trail segments and most are in the single-digit range, although a few are in the low double digits.


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## endo_alley (May 28, 2013)

We with the local mtb trail group have been building a lot of trail recently with the USFS. We have been asking and getting mostly shot down about berming our climbing turns on forest service land. The forest service only allows out sloped turns. Just last fall they began letting us berm the turns occasionally. When bermed in conjunction with a grade reversal at the top and another at the bottom, the berms hold up better than the out sloped turns. That (previous)graphic tells it all. Grade reversal at the top of the turn is important for shedding water. Out slope the trail everywhere it is possible. A lot of our western Colorado terrain is pretty steep in the back slope. We use a lot of fairly big boulders in the berms (200-500 lbs). Set them battered so they appear to want to roll uphill or into the turn. This counters the outwards pressure from trail users in the turn. Use a chord to make a perfect semi circle if possible. We try to make climbing turns about 15' to 18' in radius if terrain allows.


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## Walt Dizzy (Aug 18, 2003)

You didn't ask, but I'm going to give you my opinion anyway. What you should be thinking about before the way things look, is how much labor you are willing to put into building a turn. Switchbacks require building a substantial crib wall on the downhill leg, and moving a lot of dirt to fill behind it. 

The old standard, the IMBA rolling crown switchback averages about 80 hours of hand labor to build, and that's assuming the material is available nearby. A less rigorously designed switchback turn should take less time to build.

Insloped (bermed) turns have caught on not only because they are more fun to ride, but they require less labor to build.

I don't know what the generally accepted limits are for the hillside slope for bermed turns. My guess is you can mitigate the shortcomings/limits of bermed turns to a degree by flattening them out. Dig the upper leg back into the hillside and use the spoils to build up the lower leg. Make a kind of a hybrid between an insloped turn and a switchback. Perhaps this is what Cotharys was getting at?


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## ZigaK (Sep 9, 2009)

https://springsladelodge.co.uk/wp-content/uploads/2015/11/Cannock1.jpg


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## endo_alley (May 28, 2013)

Switchbacks are used on the steepest hill gradients. They can be impressive features when done well. We usually budget a full day for an experienced six man crew to build a switchback. The last one we built even required a gas powered jack hammer to get through some giant boulders. And of course lots of rock bars and boulder carriers. But our well made bermed climbing turns which overlay a solid rock structure, with the proper grade reversals and drainage are holding up year after year also. One issue we are always going over with the USFS is to lay the trail out such that the turns are on the flattest terrain possible. But that often conflicts with other objectives and directives they have. Also the local USFS trail people seem to dislike grade reversals. They prefer lots of nicks and drains. We in the local group are little by little trying to advocate incorporating mountain bike standards on the layout of general purpose trails. It is pretty obvious to the USFS, that when they need work done, it is mountain bikers alone who show up to help. No other user groups show to repair trails. The forest service personnel are trained in standards which date back decades, long before mountain bikes. And everything we build must be engineered to hold up under horse traffic.


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## dirt pirate (Feb 26, 2009)

This is one of several I built over the summer. As stated in posts above, find the flattest spot on the slope and be ready to spend some time making it right. Short cuts make for years of misery.


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## KeithNorCal (Jun 7, 2016)

Must be nice to have the mechanical friend. I'll be building my trail by hand. :-(


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## hankthespacecowboy (Jun 10, 2004)

I've found the Omega shape to be one of the most critical factors in making enjoyable, sustainable turns. The "V" shape of traditional switchbacks is just plain awkward on a bike, unless you enjoy trials-style hop turns, and a "U" shaped turn needs a steep, skate-park style berm/bowl construction in order to work effectively. The Omega shape leads riders into a more correct riding form of counter-steering before the turn to make a more consistent radius. As a singlespeeder, I've found a slight berm platform helps carry more speed into climbing turns, v. trying to hold your line on an outsloped turn. Keep in mind these berms don't have to be steep-walled BMX/Dual slalom type berms. Think of something more like the tilt of roulette wheel. All you really need is reverse the standard outslope of the tread into an inslope to make the turn more effective in both directions.


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## endo_alley (May 28, 2013)

The tight switchback is necessary in very steep terrain where it is nearly impossible to create a wide bench or proper backslope grade. As in slopes along cliff bands, or slopes over 35 degrees. The best way to avoid this is to lay out the trail in such a way as to avoid turns on steep terrain. But when the land is owned by someone else, such as the US government, you must build the trail on the land they allot for the trail. By omega turns, I assume you mean a C shape where the diameter of the turn is slightly bigger than the distance between the entrance to the climbing turn and the exit from the turn. This creates a natural grade reversal at the entrance and exit. But this is in complete contradiction to US forest service guidelines.


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## Le Duke (Mar 23, 2009)

hankthespacecowboy said:


> I've found the Omega shape to be one of the most critical factors in making enjoyable, sustainable turns. The "V" shape of traditional switchbacks is just plain awkward on a bike, unless you enjoy trials-style hop turns, and a "U" shaped turn needs a steep, skate-park style berm/bowl construction in order to work effectively. The Omega shape leads riders into a more correct riding form of counter-steering before the turn to make a more consistent radius. As a singlespeeder, I've found a slight berm platform helps carry more speed into climbing turns, v. trying to hold your line on an outsloped turn. Keep in mind these berms don't have to be steep-walled BMX/Dual slalom type berms. Think of something more like the tilt of roulette wheel. All you really need is reverse the standard outslope of the tread into an inslope to make the turn more effective in both directions.


This is one of the best, most concise and well thought out trail building posts I've read here.

Definitely helps me picture how, and just as importantly WHY, to build/fix turns on steep terrain.

Sent from my XT1585 using Tapatalk


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## KeithNorCal (Jun 7, 2016)

Le Duke said:


> This is one of the best, most concise and well thought out trail building posts I've read here.


I concur. Kudos to hankthespacecowboy. That's a good description of the strategy that I'm leaning toward, basically building in grade reversals before and after every turn. Fortunately, the slope is "only" 20% and it's my land. I've already rerouted a couple of turns but I have lots more to do before I do any benching at all. Thanks to all for participating in this thread.


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## hankthespacecowboy (Jun 10, 2004)

Thanks for the kind words! Glad to help make the trail building learning curve less frustrating for others! 

One of the most recurring mistakes I made in figuring out turns was making the radius too small. An 8' radius seems enormous when you are flagging it out on foot, but once on a bike, it feels rather cramped. A 12' radius is a good baseline to work from. Keep in mind that a larger radius with a slight inslope makes it easier to keep your speed when climbing, and doesn't require as much deceleration force when descending. 

The other tricky thing about new turns is how much slower, and tighter the radius will ride when it is soft & unpacked v. how much faster & wider the radius will ride once it gets grooved in. Even with diligent tamping & packing, the line will shift further towards the outside of the turn as the trail becomes more defined, and the rider's lean angle will increase in the turn. 

Keep the increasing lean angle in mind when picking out turn anchors. Locally, we have an Open OHV area with several generations of user-created social trails weaving in and out of junipers. The junipers often serve as pivot points for the turns. In the initial phases, when the trail is soft, speeds are slow, and riders pass through the turn in a more upright position, making minimal contact with the trees. As the trail becomes more packed, and riders carry more speed through the turn, lean angle increases, and riders make more contact with the tree. At first you only brush up against a few needles; as speed & lean angle increases, the needles are torn off, and the branch becomes a knuckle-swatting, brake lever-grabbing stick. Maybe not entirely applicable in the OP's case, but something to keep in mind when picking out turn anchors.


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## endo_alley (May 28, 2013)

We try to use a 15 foot radius as minimum for a full turn. Or even a little bigger. If you build a boulder crib around the outside of the turn and inslope the bench of the turn, it shouldn't go anywhere.


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## KeithNorCal (Jun 7, 2016)

hankthespacecowboy said:


> One of the most recurring mistakes I made in figuring out turns was making the radius too small. An 8' radius seems enormous when you are flagging it out on foot, but once on a bike, it feels rather cramped. A 12' radius is a good baseline to work from. Keep in mind that a larger radius with a slight inslope makes it easier to keep your speed when climbing, and doesn't require as much deceleration force when descending.


Agreed, and this is exactly one of the things I've been trying to solve in building the trail on my own land. In order to maximize the length of the trail, as well as hopefully being able to ride the sloped land in both directions on a singlespeed, I'm incorporating lots of turns. The first section I'm working on descends to a corner of the property and then has to climb back up. The way I have it flagged out now, as you descend into the corner, almost every turn has a radius less than the turn before. So, starting at the top, I've started adding grade reversals to improve flow while simultaneously expanding the radius of the turns. As I get further down the slope, and therefore closer to the corner, I may have to completely reroute the trail since some of the turns I've flagged are so tight. Regardless, I feel like I'm making decent progress.


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## KeithNorCal (Jun 7, 2016)

Walt Dizzy said:


> Insloped (bermed) turns have caught on not only because they are more fun to ride, but they require less labor to build.
> 
> I don't know what the generally accepted limits are for the hillside slope for bermed turns. My guess is you can mitigate the shortcomings/limits of bermed turns to a degree by flattening them out. Dig the upper leg back into the hillside and use the spoils to build up the lower leg.


Excellent point Walt! Right now I'm just in the process of re-flagging the turns with a larger radius and raking the new path (I did a couple more turns today) but when it comes time to bench the trail tread I can always go a little deeper on the uphill side and build up the downhill side to reduce the grade in the center of the turn.


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## cmc4130 (Jan 30, 2008)

Vail, Keystone and Winter Park

I agree with y'all. This type of swtichback is not fun on a bike:








(I took this pic at Vail).

This was roughly a 10 foot radius berm and it was too tight for the speed (although at a slower speed, I'd say it'd be fine).









Here's an interesting way of doing a turn on a side slope:

















Must Ride: The Australian Alpine Epic Trail, Mt Buller ? Flow Mountain Bike










Grade (slope) - Wikiwand


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## jeffscott (May 10, 2006)

We have lots of old school trails....

Tight switchbacks on very steep grades...

challenging to ride up and down....

Don't see why ever thing has to b dumbed down or eliminated so everyone can ride it.


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## jeffscott (May 10, 2006)

endo_alley said:


> The tight switchback is necessary in very steep terrain where it is nearly impossible to create a wide bench or proper backslope grade. As in slopes along cliff bands, or slopes over 35 degrees. The best way to avoid this is to lay out the trail in such a way as to avoid turns on steep terrain. But when the land is owned by someone else, such as the US government, you must build the trail on the land they allot for the trail. By omega turns, I assume you mean a C shape where the diameter of the turn is slightly bigger than the distance between the entrance to the climbing turn and the exit from the turn. This creates a natural grade reversal at the entrance and exit. But this is in complete contradiction to US forest service guidelines.


Why is 35 degrees not acceptable you just have to learn to ride the tight switch back....lots of our trails double as skiing up tracks and 35 degrees is an ideal ski slope.


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## endo_alley (May 28, 2013)

jeffscott said:


> Why is 35 degrees not acceptable you just have to learn to ride the tight switch back....lots of our trails double as skiing up tracks and 35 degrees is an ideal ski slope.


 You can skin up a much steeper trail on skis than you can climb on a mountain bike. So it usually doesn't make sense to climb a bike trail on skis. Tight switchbacks are very slow turns on a mountain bike. And a lot of effort to build. A proper switchback has a nearly level bench on which the turn sits. On a very steep slope, this bench requires a well engineered crib wall to support the bench. And a lot of fill material. Climbing turns are less steep and are usually considered more enjoyable to ride on a bike.


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## jeffscott (May 10, 2006)

endo_alley said:


> You can skin up a much steeper trail on skis than you can climb on a mountain bike. So it usually doesn't make sense to climb a bike trail on skis. Tight switchbacks are very slow turns on a mountain bike. And a lot of effort to build. A proper switchback has a nearly level bench on which the turn sits. On a very steep slope, this bench requires a well engineered crib wall to support the bench. And a lot of fill material. Climbing turns are less steep and are usually considered more enjoyable to ride
> on a bike.


My point not all trails should follow your rules no a switchback does not require a level bench and a well engineered crib wall....to function well and last without maintance.

Secondly they can be very enjoyable to ride both up and down.

Some people actually use wax to skin up 35 degree slopes using switch backs and traverses...indeed was the most popular way for a very long time, and still has lots of people doing it.

Not all trails need to or even should conform to your "rules"


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## endo_alley (May 28, 2013)

jeffscott said:


> My point not all trails should follow your rules no a switchback does not require a level bench and a well engineered crib wall....to function well and last without maintance.
> 
> Secondly they can be very enjoyable to ride both up and down.
> 
> ...


If the bench is not nearly flat, then it is not, by definition a switch back. If the turn is inclined through the apex of the turn, it is by definition called a climbing turn, not a switchback. "Not all trails need to or even should conform to your "rules" Yes, all trails should conform to sustainable engineering standards. If not they will erode. I certainly didn't invent sustainable practices. But I have done enough supervised trail building to realize how important such practices are.


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## jeffscott (May 10, 2006)

endo_alley said:


> If the bench is not nearly flat, then it is not, by definition a switch back. If the turn is inclined through the apex of the turn, it is by definition called a climbing turn, not a switchback. "Not all trails need to or even should conform to your "rules" Yes, all trails should conform to sustainable engineering standards. If not they will erode. I certainly didn't invent sustainable practices. But I have done enough supervised trail building to realize how important such practices are.


What a crock

These trails have been around for many years in some cases approaching a hundred years...

Go ahead re define terms, go ahead promote rules that must apply...even though plenty of experience shows that the rules are not the same for deferent terrains and applications.

The switchbacks I refer to are switch backs and no the are not flat benches...and no they are not climbing turns and no they are not berms...and as before they have lasted intact for many years.


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## endo_alley (May 28, 2013)

I am not the one defining these terms. They have been around for many decades. As with any technical term, it pays to be specific.

Trail Construction and Maintenance Notebook - 00232839 - FS Publications - Publications - Recreational Trails - Environment - FHWA

Check out the IMBA manual. It will answer a lot of your questions and give you some good direction. https://www.imba.com/catalog/book-trail-solutions

Why are they not climbing turns you are making? Sounds like they are very tight climbing turns. All of the pictures in this post are climbing turns.

We in the local mountain bike organization have been rebuilding dozens of old poorly constructed trails in conjunction with the local forest service, the BLM, and private land managers. If a forest ranger directs us to build a switch back on a particular turn, and we wind up making a climbing turn instead, we get chewed out. Words have meanings.


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## J.B. Weld (Aug 13, 2012)

endo_alley said:


> If the bench is not nearly flat, then it is not, by definition a switch back.


That's the definition I've heard as well, the name "switchback" originated from trails cut to allow trains to pass. A train going up would continue on a flat area past the turn until the caboose/engine got to the corner and then the "caboose" would switch back and drag the train the other way.

Anyway that's what I read some time back while reading some trail gurus site (forget who) and he said that what most people consider a switchback is really a climbing turn, and that unless the topography is carefully utilized a massive amount a material is required to be moved to build one properly.


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## indytrekracer (Feb 13, 2004)

*Hand Built turns*

1st, I like all kinds of different turns, From wide radius banked turns you can rail at full speed down to tight turns that require you to bunny hop around.

On hand built trails in areas of steeper side slope, it is pretty hard to move enough dirt for wide sweeping turns and true switch backs require you to bunny hop around.

In the old days, climbing turns were viewed as bad because water could flow down the trail, through the turn, and then keep going down the lower leg of the trail.

If you are pay attention to water management and in some cases add some rock armoring, climbing turns can be very sustainable.

So on Intermediate and expert level, hand built, single track trails, I tend to build climbing turns.



















The keys are to

1. Build grade reversals at the entrance to get water off the trail before entering the turn.
2. Bank the turn which pushes water to the inside of the turn. So the inside of the turn is a drain. 
3. As you come out of the turn, add another grade reversal or armored drain to get water from the drain across the trail.

Typically I start with the crib wall that anchors the turns banking. Then pull dirt from above to lower the top trail and build the bank. If the turn ends up being too tight for you liking, just keep increasing the top radii of the turn, and pulling the dirt down to raise the berm.

The climbing turn in the picture about took 2 of us about 4 hours to build.


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## endo_alley (May 28, 2013)

When we lay out our turns, we usually establish a center point. and then string line a near perfect circle from that center line. Usually someone will have a piece of rope with knots as markers. The first knot is at 15 feet from the beginning of the rope. Then one at seventeen feet. And another knot at twenty feet. We go for the widest radius the terrain will permit. It works out best when the turn is a greater arc than a half circle (more than a C shape). More like two thirds of a circle for the arc. For this to work, the diameter of the turn must be greater than the distance measured from the entrance to the turn to the exit from the turn.


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## endo_alley (May 28, 2013)

That looks like nice country. I bet it is nice in the fall.


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## indytrekracer (Feb 13, 2004)

endo_alley said:


> That looks like nice country. I bet it is nice in the fall.


It is nice in the fall. Photo is of the Bobcat Connector at Brown County State Park. We have really good clay to work with and just enough rocks to armor and build features.


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## jeffscott (May 10, 2006)

J.B. Weld said:


> That's the definition I've heard as well, the name "switchback" originated from trails cut to allow trains to pass. A train going up would continue on a flat area past the turn until the caboose/engine got to the corner and then the "caboose" would switch back and drag the train the other way.
> 
> Anyway that's what I read some time back while reading some trail gurus site (forget who) and he said that what most people consider a switchback is really a climbing turn, and that unless the topography is carefully utilized a massive amount a material is required to be moved to build one properly.


People have been skiing for a much longer time than they have been building rail lines...the term switchback (and in whatever language as been around a lot longer than trains....

The situation missed by the definitions is steep turns on rock or any other hard material...the turns are the ones where you have to brake stand to get the rear around, or kick turn while skiing...to dismiss that type of turn is to say that lots of slick rock trails should not exist.


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## endo_alley (May 28, 2013)

An uphill climbing "kick turn" is a lot lot an mtb switchback. As one is ascending a slope and one wishes to turn back across the slope, one creates a flat stance with one's skis. Then brace ones poles, and lift the uphill ski around 180 degrees on the flat track. Parallel to the downhill ski. Next one lifts the downhill ski and brings it around 180 degrees on the flat track, above the uphill ski. Parallel to and just above the previous uphill ski. In both biking and skiing, a switchback is done one a fairly flat bench or track. And with a very tight radius.


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## J.B. Weld (Aug 13, 2012)

jeffscott said:


> People have been skiing for a much longer time than they have been building rail lines...the term switchback (and in whatever language as been around a lot longer than trains....


Not that it matters any but maybe it's both.



> switch·back (swĭch′băk′)
> n.
> 1.
> a. A sharp bend in a road or trail on a steep incline.
> ...


I'm not a skier but I would think a skiing switchback would be a little different thing than what would be considered a switchback on a trail?


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## endo_alley (May 28, 2013)

J.B. Weld said:


> Not that it matters any but maybe it's both.
> 
> I'm not a skier but I would think a skiing switchback would be a little different thing than what would be considered a switchback on a trail?


Not so much different when climbing on skis. A switchback is a turn on a pivot point. A climbing turn is an arc shaped turn. Of course this has nothing in common with turns used when descending on skis.


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## cmc4130 (Jan 30, 2008)

endo_alley said:


> When we lay out our turns, we usually establish a center point. and then string line a near perfect circle from that center line. Usually someone will have a piece of rope with knots as markers. The first knot is at 15 feet from the beginning of the rope. Then one at seventeen feet. And another knot at twenty feet. We go for the widest radius the terrain will permit. It works out best when the turn is a greater arc than a half circle (more than a C shape). More like two thirds of a circle for the arc. For this to work, the diameter of the turn must be greater than the distance measured from the entrance to the turn to the exit from the turn.


I don't quite understand what you mean by 15, then 17, then 19. Are you talking about different turns going down the slope?

Or are you talking about an increasing radius through the single turn......? (Because, if so.... I have thought of doing the same thing on a hillside. The rider is increasing speed going down the slope.... so why not increase the radius as the turn progresses? )

If you watch skiiers creating turn patterns on a hillside... none of those arcs have a circular radius....

Physics Of Skiing




























The Complete Encyclopedia of Skiing?EpicSki Skiing Glossary - EpicSki Community

.


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## endo_alley (May 28, 2013)

No. A single uniform radius per turn if possible. The various lengths allow one to build turns of various radii. Where larger radius is usually better. But not always possible.


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## cmc4130 (Jan 30, 2008)

endo_alley said:


> No. A single uniform radius per turn if possible. The various lengths allow one to build turns of various radii. Where larger radius is usually better. But not always possible.


Right. I've built a lot of berms https://forums.mtbr.com/trail-building-advocacy/bermed-corner-radius-sizing-724304.html and try to study exactly how much speed corresponds with what turn radius.

But, another factor is that in pump track and dual-slalom, situations it's easier to have steep faced "bowl corner" style berms. But out on minimal-maintenance trails, you can't expect the steep face to stay that way over time. So, with less "lean," you end up needing a bigger radius.



















Video: 40 MPH Down a Concrete Bobsled Track? On a Mountain Bike! | Singletracks Mountain Bike News


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## J.B. Weld (Aug 13, 2012)

cmc4130 said:


> The Complete Encyclopedia of Skiing?EpicSki Skiing Glossary - EpicSki Community


I couldn't help but notice that extensive glossary didn't mention anything about switchback turns.


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## endo_alley (May 28, 2013)

I think the EPICSKI thing is about going downhill skiing on moderate slopes. The switchback idea is about skin climbing climbing steep slopes.


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