Building Trails

tomato paste

Active member
Mar 18, 2019
220
142
Germany
I'm hoping there are some smarter more experienced folks here that have an answer.

I'm building a trail for beginners (we have none here), and I had thought I had chosen a fairly mellow but intelligent line through the woods, which I proceeded to clear. After a brief rough in, I tried riding it, and found I am not accelerating, I decelerate to a stop and must pedal through it all. Obviously as the line is benched and compacted, friction should decrease, and I should see more acceleration. But does anyone have a good rule of thumb on how to judge whether a line may be 'not steep enough'?

If I calculate the gradient per short section, I'm seeing stuff like this:

20m, 4%
5m, -1% (upslope)
20m, 6%
15m, 0% (flat)
5m, -1% (upslope)
40m, 2%

And, I'm starting to think, regardless of how compacted I can get the dirt, this thing may actually be much too mellow, and the sections where I though I'd bleed off speed are irrelevant because people won't be going fast enough. Anyone have insight to offer?
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
13,805
20,498
Brittany, France
I only do it based on feel and eye. I wouldn't have a clue how to put that into computational explanations or rules.

It's probably harder the easier you're trying to make them ? As the relevance of too fast to too slow is very close in the scheme of things, compared to just making things "challenging" .

So no, no insight .. but it's a bump .. :)
 

Mart-e

Member
Dec 13, 2020
66
36
Australia
Where you notice the trail line features naturally fall away, here will be where the trail offers for flow.... ideas with adding for flow creates momentum.... checking out how pump trails work, another mtb skill for progression that you then can splice ideas with your new trail..... adding berms to will also hold for flow.... where other trail features occur, another natural fall away place a jump backed behind this natural fall away as a lander, create some rollers and see where this takes you.
Enjoy the being dirt art of creativity.
 

tomato paste

Active member
Mar 18, 2019
220
142
Germany
Have you asked a beginner for feedback? :unsure:

I'm a beginner :LOL:.

I can't ask for feedback because the trail is not authorized (long story: the new trail replaces an existing trail that is labelled for beginners but was built entirely along a fall line, and it has become so steep, rutted, and rocky that its not safe to ride for entry learners, local land management is unfortunately so complex, due to intersecting land boundaries at multiple levels of government, that its impossible to get approval from all parties to correct the trail).

I thought my eyes would be sufficient to judge where the line should go, but the rolling friction factor of a roughed-in trail is substantially higher than a completed, compacted, benched, bermed trail. I need some kind of heuristic that tells me 'going X fast on rough trail = Y velocity on a finished trail', so that when I ride a rough-in, I know the line is sufficiently steep.

Figuring out those approx gradients, comparing them to IMBA recommendations, really doesn't tell me anything useful at the moment. Because the trail is not authorized, I really need to get the line right the first time, to minimize impact to the land.

I'm thinking the best way forward ATM is simple to finish the first few sections entirely, and then see what the difference is from the original rough-in deceleration. If the 100% finished section doesn't actually work, abandon the project at that point, as additional clearing to correct this error should really be approved first.
 

Slowroller

Well-known member
Founding Member
Jan 15, 2018
494
496
Wyoming
You've built a nearly flat trail, so yeah, you'll need to pedal on it. You can build a beginner trail all at 6-8%, and it'll be easy to ride if it's wide and smooth, harder to ride if it's narrow and rocky. My point is that grade isn't the only factor in difficulty.
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,523
2,407
La Habra, California
I'm a beginner

and it has become so steep, rutted, and rocky that its not safe to ride for entry learners,

A beginner does not have the right to alter an existing trail because it is too difficult for him to ride. He should strive to develop his skills so he can ride the trail like everyone else. Creators of "P-Lines" are respected by few, and despised by many. Don't be that guy.
 

tomato paste

Active member
Mar 18, 2019
220
142
Germany
A beginner does not have the right to alter an existing trail because it is too difficult for him to ride. He should strive to develop his skills so he can ride the trail like everyone else. Creators of "P-Lines" are respected by few, and despised by many. Don't be that guy.

If there are no trails for people to learn on, skills can't be developed, and the sport won't grow.

More importantly, the state of the existing trail is independent of any rider. People who are high-skilled don't use the trail, because it's a poorly constructed trail (15-30% gradient, straight, rutted, rocky). The trail violates IMBA standards, as its constructed along a fall line and exhibits high degrees of water damage. Beginners damage their bikes (entry level equipment) and injure themselves, which increases liability for everyone in the local area, including the bike club, all riders, medical and medical evac personnel.

I cannot disagree with your statement more. Trail construction is also a part of learning the sport. And even beginners can identify poor work of lazy 'expert' riders, who often construct trails without any intent on maintaining them for safe future use. Or, in this case, where the trail is a boundary between various districts, which meant that even if an 'expert' cleared that path the first time, they had zero input to the trail's construction--that was fixed from the beginning.
 
Last edited:

EezyRider

Member
Sep 23, 2020
43
33
Lincolnshire
Once you know where the trail will begin and where you want it to end, we found it best to scrape out a short section of trail then ride it, the more it’s ridden the more compacted it becomes.
Ideally start with a good down slope to get speed going then traverse the hill, use berms on steeper or tighter turns but keep flatter turns without berms. When your happy with the flow of the section, move on to the next.
Pump bumps and little gapless jumps will help maintain/gain speed and short, gentle uphill sections will extend the trail, ideally these will be followed by a short steeper section to keep flow going.
Once you’ve got a trail that flows how you want it you can start adding more features and berm some of the corners as necessary.
In my experience drainage is one of the biggest issues with flatter trails.

If you need to armour any areas of the trail always put a membrane down first as this will stop your chosen material disappearing into the dirt. Never use bits of dead wood or branches to build berms or features, they won’t last. Larger logs will be ok in the short term but nothing beats compacted dirt.
This approach worked well on loam over clay and chalk soil.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

523K
Messages
25,837
Members
Join Our Community

Latest articles


Top