# What Standards and Tools for Trail Pitch do you use?



## zachi (Jul 25, 2006)

I am curious what guide lines different agencies or landmangers have required for pitch. Most people know IMBAs. What about USFS etc...are they the same from region to region?

Also, what techniques or tools do people use when shooting these in? IMBA recommends an inclonometer, but these seem pricey for beginners.


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## Fletcher-Love (Nov 14, 2009)

0 to 15. With 15 percent grade being the absolute max for having any chance of it not just washing away. I believe those are the grade perimeters for our USFS up here. There are all sorts of variables that come into play depending on what what your building material is and what the predominate climate is. Land managers adjust their building guidelines within that range accordingly. IMBA basically adopted the Forest Service guidelines for building hiking trails... added some bermed corners, increased the outslope of the trail tread, added some grade reversals for drainage and maybe throw in a bit of rock armoring for high use areas and then Ta Da!!!! Mt biking trail. Otherwise the standards are pretty much the same. A well built hiking trail makes a well built bicycling trail as far as sustainability is concerned and as far as I know, the clino is still the best tool for laying out grade in the field.


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## indytrekracer (Feb 13, 2004)

*clino*

If you don't use a clinometer, your just guessing. And you will guess wrong. Get the clinometer!


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## Loren_ (Dec 3, 2006)

There's a $.99 clinometer app for the iPhone that's pretty good. Sighting along an edge of the phone isn't as accurate as a real clinometer, but the price can't be beat.


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## Skookum (Jan 17, 2005)

Fletcher-Love said:


> A well built hiking trail makes a well built bicycling trail as far as sustainability is concerned and as far as I know,


Weeeeellllllll.... not really. For multi-use it really helps to have an eye for the bike to reduce conflict, improve sustainability... There is a newly built hiker built trail here that is fast becoming more popular for mt. bikes, and they made quite a few errors. One would be an outsloped turn with a ditch for drainage under the outslope.(many of them actually) Alot of these turns have poor sight lines, and they all come after a long straight downhill.

What happens then is you have bike coming downhill and you make the turn too hot, if it's wet, you slide out, progressively making more of an outslope, if there is a hiker on the bottom side now you have a rider struggling with control on precisely the worst possible spot you would want an encounter like that to happen.

What is better would be a trail routed similarly, but then before the turn you flag the trail up a hill to sap the riders speed before he get's to the turn. Then you have a keyhole shaped switchback that's insloped in the turn with a reverse grade built off the bottom side. Now you have a trail where the wheels are working with the dirt and will not erode the trail, and you also have a trail that is safe for bikers, and a trail that will reduce any possible conflict.

That is just one example of this trail there are other issues that might be passable for hikers, but are light years behind the proficiency of a good mt. biker trail builders capacity.



Loren_ said:


> There's a $.99 clinometer app for the iPhone that's pretty good. Sighting along an edge of the phone isn't as accurate as a real clinometer, but the price can't be beat.


Wow that's cool! As long as you're close to a +/- 2 degrees that ain't bad! There are trails where you want to be precise, but for a typical multi-use XC trail...


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## Fletcher-Love (Nov 14, 2009)

I stand corrected in regards to building turns. That is the biggest difference between hiking, mt biking and motorcycle trails,....how you deal with the draining the corners.


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## slocaus (Jul 21, 2005)

We work with City, County, State Parks, USFS. A couple of our land managers are sharp on trail build standards, others have no idea. Basically what others have said, use IMBA standards and adjust for your soils, ground cover, climate, etc.; -15 to +15% is what we use (rarely over 10-12% in our climate), mind the half rule, poles and a clinometer. A clinometer is essential for us in our chaparral. We look at possibilities and then go to rough flag, and our movements are back and forth until the clinometer tells us we are ok. Sometimes the pole is in two feet of brush, sometimes in six feet over 25-50 foot sections

Sighting pole to pole gives certainty on grade, we use two to three.









We use a 25 foot rope with a knot in the middle for fine flagging and mark every 12.5 feet.









Generally with our open land (central coastal CA), grade reversals every 50 to 75 feet.

















The above photos were taken at a training session in an old ranch that was just given to the city for open space. We do not typically have grasslands, but heavy chaparral.

The distant chaparral is what is typical for our area.









We use pin flags, red for trail, blues for drains at bottom of grade reversals.









For the most part, our terrains is wide open, so changes of direction are tough, or users will cut corners on trails. We do long meandering sections to avoid this.









Very few trails have enough brush to do switchbacks.


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## The Prodigal Son (Apr 22, 2008)

zachi said:


> I am curious what guide lines different agencies or landmangers have required for pitch. Most people know IMBAs. What about USFS etc...are they the same from region to region?
> 
> Also, what techniques or tools do people use when shooting these in? IMBA recommends an inclonometer, but these seem pricey for beginners.


zachi, I work with Matt, at ACE, who was up in downieville learning some mechanized trail building techniques recently. I remember riding with you back in 1995, when Steve Lyles told me to give you a call. I still have a picture of your Toyota hauling bikes with it and my suburban straight up that mountain above Downieville. I love reading about all your new trails and plan to come visit and ride everything.

I took a class on flagging in a new trail and most participants did not have a natural ability to flag a good line. They looked at where the trail begins and where they had to go and simply went in a direct line towards the top. They did try to keep the climb below 15%, but they really missed the point.

Riders prefer grade reversals as often as possible. Recovery sections, as some call them. I would never lay out a trail with over 10% grades and I would take a trail someone else thought should be 3 miles to climb up 1500 feet and stretch it out to a five mile long trail. This allows some actual downhill sections on the climb, or uphill sections while decending.

Every time I am on a trail that has 15% grades, I can spot all the increased damage to that trail by the super accellerated water flowing down it or across it and all the loose rocks that quickly pile up on the drains. Trails with over 10% grades require massive maintenance to keep them from eroding. I just cannot understand why I see so many trails built as though the builders were in a big hurry to get to the top of the mountain, when they could easily have added a mile or two and made the trail infinitely more sustainable, not to mention more bike friendly.

Keep up that great trail work whacky zachi.


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## zachi (Jul 25, 2006)

What I see that is missed in the inclonometer conversation is identifying your target audience. 

The type of person who would research and purchase a $100+ dollar sighting tool is probably not in the trail building group that would mostly benefit. In a couple IMBA trail workshops, when I asked about this, the answer both times was that Land Managers see the inclonometer as more professional. The group that would mostly benefit in my mind are not the ones who work with land managers. 

There are the people who design and build a lot of trail - this group is so familiar with pitch that the tool is barely used. And if so, to check and confirm their work rather than using it like a life line thrown out 100ft ahead of them. 
This is a mentor group and there are quite a few on this list. Great gold to each other and the rest of the categories.

The second group is the responsible trail group leader, usually a professional in another aspect of life, used to conformity with authority, rules and standards. Will invest in an inclonometer and read 'trail solutions'. Has reached the highest plateau of practical available knowledge and possibly needs to relax and get FLOW and FUN. 

The 3rd and most important group is the trail user who is inspired to build trail. Does not feel drawn to the structured IMBA environment, perhaps does not want to, or is in a position to work with land managers(illegal trails) etc... 
For this group, simple techniques to establish grade, like with a $8 sight level seems more appropriate. A friend who paces(24" steps) 50 steps across a contour can then step up the grade till his feet are in the sight line of the shooter. 5%. 
Even better is our introduction of the Beerinclonometer (Beering-clonometer) Dos equis (clear glass) works great. Go out with a friend to the proposed route, share half the beer, who ever is positioned lower (going up or down grade) holds his thumb over the opening of the beer and then with the beer held horizontal and the knuckle of your thumb near your nose... sight down the water level of the beer. Using the same technique mentioned above for a sight level. 
The introduction of techniques like these by the center or 1st group would encourage emerging trail builders to adopt pitch concepts without the purchase of a $100+ inclonometer. It would create the concept of pitch as fun and easy rather than "professional and exclusive". Better yet, the center group could utilize the 6pack beerclinometer as a way to adapt more flowy and undulating trail!

PS this is not a patented technique and is available as an
open source concept.


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## Trail Ninja (Sep 25, 2008)

$1 clinometer= 
- 1 plastic protractor from an old math kit.
- 1 plastic drinking straw taped along the straight edge of the protractor (to sight through)
- 1 piece of string hung from the center of the protractor
- 1 washer to weigh the string down.
- 1 stick with a mark on it at your eye level to sight to

Hold the protractor with the straw at the top and the curved side down. Look through the straw. Note where the string is.

Kind of hard to do with one person but it can be done.


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## Visicypher (Aug 5, 2004)

I try to stick with ±5%. max limit is ±15%. I try to stick with IMBA standards, but sometimes don't.


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## faceplant72 (Oct 25, 2009)

what is conversion between %grade and degrees?
I had always thought 100% grade was 45degrees. 
Btw growing up with on timber/cattle ranch an Abney eye level (under $50) was always the tool of choice for this type of task


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## Visicypher (Aug 5, 2004)

inverse tangent of the decimal grade....i.e. to find the degrees equivalent of a 5% grade, the equation would be inverse tan of .05

Nerd lesson is now officially over.


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## bweide (Dec 27, 2004)

We use fishing sinker/protractor "clinometers" for our trail design classes to teach measuring grade. People seem to grasp the concept easier than when using the clinometer. We find that grade measurements made with the fishing sinker/protractor "clinometers" are usually within plus or minus 2 percent of the true clinometers. This seems like a pretty wide tolerence for measurement accuracy but this would still help make better layout decisions. 

It is important to measure trail grades because it is damn near impossible to eyeball them. Awile back I was laying out trail at the mid point between two widely distance flags. I walked up and down the hillside until I found a spot that looked like it had an equally steep grade to the flags I both directions. I measured the equal grades with a clinometer, one was 12 percent and one was 4 percent.


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## digdirt (Jun 21, 2009)

Sounds like most folks are going with the target grades published by IMBA in their literature, which is great. My understanding is that these grades were adpoted from the Forest Service standards, so it's nice to have that continuity.

As far as Forest Service standards go, it depends on the designed use and trail class when looking at target grades and short pitch maximum. For example, if the designed use is bicycles, and it is a trail class 2 (typical for less developed trails) the target grade is 5-12% with a short pitch maximum of 25%. Short pitch being no more than 200 feet in a stretch. There is a maximum pitch density also that is something like no more than 10-30% of the trail meets the maximum pitch number.

So you really should know a couple of key factors like designed use and trail class in order to plan out your trail. Most land management agencies have this information somewhere in their planning documentation.

Many compasses can by found with a built in clinometer for somewhere between $30-60. Try Forestry Suppliers as a source...nothing like a tool that serves more than one function. As others have said, this is a basic yet critical tool for trail layout and design...you're just guessing without one.


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## woodway (Dec 27, 2005)

We use IMBA standards. If a land manager is not familiar with them, I give them a copy of the IMBA trail building book. Why re-invent the wheel?

If you are going to do a substantial amount of trail layout, just get a clinometer. Especially here in the woods of Western Washington, it's a heck of a lot easier to push through and over heavy brush/blowdown/undergrowth with a small clinometer then some sort of knocked together tool.

FWIW, *inclinometer* is the more general term for all devices that measure tilt. The forestry version is generally referred to as a *clinometer*. No idea why the difference, but I do know that a good clinometer sure makes trail layout a lot easier!


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## bsieb (Aug 23, 2003)

*The real thing*



zachi said:


> Even better is our introduction of the Beerinclonometer (Beering-clonometer)...


you are one SAVVY trail builder dude!


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## TrailMasonJones (Apr 24, 2011)

most good compass have a inclomerter that can be used 5 degrees is close to 10% but the dedicated clinometer is best 10% is 10%. I will use my compass inclometer while scouting new terrain but when it comes time to start ruff flaging i always come back to the dedicated clinimeter. Yep im so nerdy i carry both


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## Walt Dizzy (Aug 18, 2003)

It is important to measure trail grades because it is damn near impossible to eyeball them. Awile back I was laying out trail at the mid point between two widely distance flags. I walked up and down the hillside until I found a spot that looked like it had an equally steep grade to the flags I both directions. I measured the equal grades with a clinometer said:


> Oh man, this is so true!
> 
> I've tried the "eyeball" method too with similar results. For several years I've been fixing trail that was laid out by someone else's eyeball. A $125 tool only seems expensive until you have to go back and rebuild a couple of miles of rutted trail.
> 
> ...


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## Ridnparadise (Dec 14, 2007)

The interesting thing about grade is that the approach to it is entirely different over 1km versus 10m. Assessment of grade is so relative to what you are building. The berm thread shows it in pictures - the "grades" involved with berms (4x courses and modern AM trails etc also) are so different to XC trail that clinometers etc could get totally different readings every metre.

There is no problem with grades of up to 30 degrees unless you plan to go "straight" down them. Flowing contoured traverses as well as jumps, re-entry turns and short plummets can be enjoyed up and down. Make it right and the thrill of climbing a short and tech 25% grade may be greater than the thrill of going down it. Something you just have to conquer to feel like you've made it as a local rider.

I'm not sure that any clinometer (99c i-phone app and a 150cm stick maybe) can tell you what it feels like to ride a piece of trail. There's no alternative to careful emotional mapping of a zone. Not altitudes and contours, but "this trail should go there, so how can I do it if at all". One person cannot get this right. It takes love and one person's love is another person's jail-time. Look, look, look and learn to love the feel of the place by just hanging out there. Let it speak to you. The trail wants to be there, but it does not talk to clinometers. Perhaps it is obvious I do not have to rush what I work on, at least until the digging starts.


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