Trail damage analysis for Fat Tires?- Mtbr.com
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  1. #1
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    Trail damage analysis for Fat Tires?

    Has anyone done a Trail Damage Assessment comparing fat tires with "standard" mtb tires? I feel certain fat tires would do substantially less damage than a 2.3” or narrower tire. This could be a HUGE selling point for these bikes. Heck, parks that close with the first sprinkle of rain may even think about changing their policy on closing the trail if it can be shown fat tires don’t cause a problem…I can even see a time when ONLY fat tire bikes are allowed on some (many) trails.

  2. #2
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    I think we have all noticed how much less impact our tyres make. There's quite a few pics in this part of the forum to illustrate that.

    It would be good to see a formal study made. Maybe the big fatbike companies could sponsor this. More trails open = more fatbikes sold.
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    Yup, On our trails "FAT TIRES" act like steam rollers and mush down the ruts. They are a great trail maintenance tool!

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    I'm not an expert on trail maintenance, but I don't think fat tires would not damage a wet trail. There's no doubt it will do less damage than a normal tire The wider tire would put less pressure on the trail, but the dirt would still be compressed under the tire. The dirt that you just rode over is now lower than the dirt around it and will hold water. The rules should stay cut and dry where if your tires leave a mark get off the trail and if it's raining, get off the trail. People don't stay off of wet trails as it is now. We don't need to give them the excuse of "Oh well I'm on a fat bike so it's ok."

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    If there were going to be some sort of discrimination based on tire width, it would also need to be based on rider/bike weight as well. A 98lb person on 2.1" tires at 20psi will probably leave as much of a mark as a 300lb person on 4.5" tires at 8psi. Good luck getting the park to ban fat people.

  6. #6
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    Quote Originally Posted by Chrispy009 View Post
    ...The rules should stay cut and dry where if your tires leave a mark get off the trail and if it's raining, get off the trail. People don't stay off of wet trails as it is now...
    We leave even less of an impression than a person on foot. So if they are going to ban anything, start with the heavy booted people.
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    This will be a topic of ongoing discussion at our local N. Mn bike club meetings. We are closely allied with a state trail here and experience with the resource (soil type, current conditions, expected traffic, etc.) will likely guide some evolution. Some of our trails dry out literally in minutes, others not so much.

    Riding prepared and maintained singletrack is a relatively new thing for me; I started so far back that there were NO purpose-built MTN bike trails anywhere, let alone the midwest. You took potluck; but because there were so few of us it was hard to imagine much damage taking place. Because MN is a wet place with lots of surface water, I would actually like to see some research done into the MTN bike equivalent of the mud bogs that ATV and FWD folks seem to like.

    Cyclocross comes close, but I'm not looking for a race, just recreation.

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    Long rant below...



    I believe I started a thread about this same topic a while ago, and even brought it up on my local forum for which I was thoroughly reamed for thinking I deserved special treatment because my bike is "different". I even went through the trouble of taking pictures as evidence to prove my hypothesis. Following the scientific method and what not. In the end, it's all about the club maintaining a "consistent message".

    Here's the thread from my local forum (you may have to join to read): Friends of Off Road Cycling

    I was on the brink of quitting the club after that episode. If the trails were that bad I would not have ridden, since sloppy trails aren't fun to ride anyway. But some people thought it was important to make an example out of me (for whom I don't know since it was a members only forum).

    Here's some more links, most which I participated in:
    https://forums.mtbr.com/fat-bikes/le...ce-764342.html
    https://forums.mtbr.com/fat-bikes/tr...rs-689389.html
    https://forums.mtbr.com/fat-bikes/fa...ge-686077.html

    Some pics from my ream ride:

    A "rutted" sloppy section before fat tires


    After my fat tires, Larrys obviously


    Clearly the fat tires have a steamrolling effect on the trails. But don't argue this with anyone. It's best to just keep your mouth shut and ride based on your best judgment.

    In the future, as fatbikes catch on, we may see the mountain bike community split into 2 groups, people who ride fat and people who don't. However, it is important that everyone keep the peace and continue to work together to keep land access and trails maintained.

  9. #9
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    Quote Originally Posted by Northender View Post
    If the trails are wet you don't ride on them. It doesn't matter whether your tires are fat or skinny. Any tires will cause damage and your pictures illustrate that very well. I find it both Interesting and insulting that you would use the scientific method to justify your riding of wet trails and breaking club policy. My inner scientist commends you for this, but rules are there for a reason. Quitting the local club because you didn't get your way might be viewed as childish and petty. Just respect the club, its rules and its members and ride your bike. Simple. I'm sure fatbiker's will carve out their own niche in the cycling community, but there will be lots of people who still ride multiple disciplines with fat biking being the newest flavour.
    Northender, if you read the linked thread you would see I had permission to ride from the trail steward as he was as interested in the results of my experiment as myself. In any case, the trail system was officially open and that was the point that ultimately ended the thread.

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    I ride my Mukluk on walking trails all the time. Occasionally, I encounter walkers, who question my right to be there, and all I say is 'Have a look at your footprint, then have a look at mine...' 99% of walkers actually go 'Oh yeah!' And because I was polite we end up in a conversation about how awesome my bike is and how so many more people should ride them...

    I don't think talking about this issue helps, going out and riding and having people realise is where it's at...

  11. #11
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    Quote Originally Posted by Northender View Post
    If the trails are wet you don't ride on them...
    Over here that means you don't ride a bike except for the one day of summer.

    Fortunately we have the right to access and do not rely on permission in Scotland.
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    Quote Originally Posted by dgw2jr View Post
    [IMG]
    Clearly the fat tires have a steamrolling effect on the trails. But don't argue this with anyone. It's best to just keep your mouth shut and ride based on your best judgment.
    www.ottawavelo.com - MTB & Gravel lifestyle in Eastern Ontario

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    My experience has been this: On fresh thawed mud, where the ground has thawed down 2 or 3 inched but it's still frozen hard underneath, it doesn't matter if your tires are 1" or 5", yer gonna be leaving ruts.

    It's a tough one. We all want to ride and we all want to believe OUR bike isn't the one doing the damage. But wet trails and mud can be damage waiting to happen. If there's standing water on the trail, yer probably better off not riding.

    I'm going with this from now on: if it would piss me off that someone else was riding on the trail in the condition it's in, I probably shouldn't be riding on it either.

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    yesterday the unusually warm weather around here brought out huge numbers of people. The trails were muddy and the hills were swampy. I had to wade through hundreds of pedestrian footprints dug way down into the mud before I got there. On a steep climp on damp, I leave almost no mark. But yesterday I left a rut only a fat bike could make - a real dinger! I think the only reason there werent alot more marks like that was because everyone else HAD to walk their bikes. So to be fair, I can get into way worse than they....

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    Quote Originally Posted by roobydoo View Post
    yesterday the unusually warm weather around here brought out huge numbers of people. The trails were muddy and the hills were swampy. I had to wade through hundreds of pedestrian footprints dug way down into the mud before I got there. On a steep climp on damp, I leave almost no mark. But yesterday I left a rut only a fat bike could make - a real dinger! I think the only reason there werent alot more marks like that was because everyone else HAD to walk their bikes. So to be fair, I can get into way worse than they....
    I think that's kinda the blessing and curse of fat bikes- you CAN ride through stuff that would make guys on standard MTBs turn back.

    I don't want to argue boot prints vs tire tracks with anyone- I think that's a distraction. Unfortunately, people don't see bootprints and foam at the mouth like they do with tire tracks.

  16. #16
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    Quote Originally Posted by buckfiddious View Post
    My experience has been this: On fresh thawed mud, where the ground has thawed down 2 or 3 inched but it's still frozen hard underneath, it doesn't matter if your tires are 1" or 5", yer gonna be leaving ruts.

    It's a tough one. We all want to ride and we all want to believe OUR bike isn't the one doing the damage. But wet trails and mud can be damage waiting to happen. If there's standing water on the trail, yer probably better off not riding.

    I'm going with this from now on: if it would piss me off that someone else was riding on the trail in the condition it's in, I probably shouldn't be riding on it either.
    There's even more to it than that though. The percentage and type of fibrous content in the mud makes a huge difference.

    Then there's also the question of what actually constitutes 'damage'? Is an extremely shallow, broad, BFL trench actually less of a negative regarding trail quality than deep foot/hoof prints in the trail? It's certainly more visually appealing to us, but what is the actual, physical negative effect on the trail, not just our subjective user experience?

  17. #17
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    This is a picture of a section of track that had several thousand bikes racing over it in wet boggy conditions a few weeks earlier.



    The biggest damage is recent from a horse ridden on it.
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    Quote Originally Posted by sean salach View Post
    There's even more to it than that though. The percentage and type of fibrous content in the mud makes a huge difference.

    Then there's also the question of what actually constitutes 'damage'? Is an extremely shallow, broad, BFL trench actually less of a negative regarding trail quality than deep foot/hoof prints in the trail? It's certainly more visually appealing to us, but what is the actual, physical negative effect on the trail, not just our subjective user experience?
    Agreed.

    But you know how it is, "my footprints aren't the problem, it's your tracks!"

    I remember all these arguments from the first time we had them and we lost access to so many trails. Hope we don't lose more.

  19. #19
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    Quote Originally Posted by sean salach View Post
    Then there's also the question of what actually constitutes 'damage'? Is an extremely shallow, broad, BFL trench actually less of a negative regarding trail quality than deep foot/hoof prints in the trail? It's certainly more visually appealing to us, but what is the actual, physical negative effect on the trail, not just our subjective user experience?
    Indeed. The trail itself is "damage", so defining trail damage is mostly in the eye of the beholder/user...

  20. #20
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    I've found that skidding around corners, my fat tires dig in less then my skinny tires. Also, when I slide to a stop, the fatter tires slow me down quicker, leaving less of a skid mark.

  21. #21
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    Quote Originally Posted by buckfiddious View Post
    I think that's kinda the blessing and curse of fat bikes- you CAN ride through stuff that would make guys on standard MTBs turn back.
    I believe the saying here in Wisco is: "four wheel drive means you just get further into the woods before you get stuck."

    Quote Originally Posted by buckfiddious View Post
    I don't want to argue boot prints vs tire tracks with anyone- I think that's a distraction. Unfortunately, people don't see bootprints and foam at the mouth like they do with tire tracks.
    The salient difference is that once it rains again, footprints tend to make puddles and tire tracks of any width or depth tend to make rivulets. My experience with much of the soil in south-central Wisco makes this a plausible argument.

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    Quote Originally Posted by MauricioB View Post
    I believe the saying here in Wisco is: "four wheel drive means you just get further into the woods before you get stuck."



    The salient difference is that once it rains again, footprints tend to make puddles and tire tracks of any width or depth tend to make rivulets. My experience with much of the soil in south-central Wisco makes this a plausible argument.
    Funny- my dad used to tell me that all the time growing up in Indiana...

    And that's the same experience I've had up here in Wisconsin.

  23. #23
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    If there is a trail that you can see...that is the damage! However, any trail can be damaging to the surrounding environment, or not. For instance a jeep trail through a salmon fishing stream probably wouldn't be good. A well maintained jeep trail through a large forest might have little to no affect on the surrounding area. If we are going to use our parks we have to be able to respect that some areas will have to have no traffic and others will have managed traffic.

    I think trying to justify one tire size over another is not really going anywhere...the management of it would be too cumbersome. Would someone have to measure tires like they do at the start of cyclocross races? What about motorcycles with large low volume tires? Sometimes its just easier to have black and white rules...and then fight to get areas dedicated to bicycles with proper maintenance and trail building.

  24. #24
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    I hike AND bike, as do most of the folk I know.....

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    Almost all the walkers I come across are nice friendly people as are the people on horses.

    Besides, I regard a ride as a bit of a failure if I haven't had to get off and walk at some stage.
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  26. #26
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    Quote Originally Posted by Velobike View Post
    This is a picture of a section of track that had several thousand bikes racing over it in wet boggy conditions a few weeks earlier.



    The biggest damage is recent from a horse ridden on it.
    Similar story here:

    A huge fuss was thrown about this massive destruction of trail. There's one fat tire track, my Nate track at the top of the image...


    And after one large group ride on a nice sunny 70 degree day...


    Yea...

  27. #27
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    Quote Originally Posted by Velobike View Post
    Almost all the walkers I come across are nice friendly people as are the people on horses.

    Besides, I regard a ride as a bit of a failure if I haven't had to get off and walk at some stage.
    That is my experience with walkers and horseback riders as well.
    Latitude 61

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    .................................................. .....
    Last edited by Northender; 03-15-2012 at 09:45 AM. Reason: Sick of this thread

  29. #29
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    Quote Originally Posted by Northender View Post
    Well I guess I'm 0:2 with you guys. My experience with hikers isn't as pleasant as the rest of you. I've seen hikers damage trails, but walking on them too early in the season, litter, destroy trail features and trample through closed off reclamation zones. In my neck of the woods its the cyclists who maintain the trails and hikers who poach them.
    Hikers are friendly around here. We (the cyclists) do the trail maintenance as well. The equestrians are the most destructive, least friendly, and don't do anything to maintain the parks in our area. Their behavior has them on the brink of banishment. They should really take a step back, look at how their user group is behaving and realize they may soon lose access to the one park in the city that they have the PRIVILEGE to ride.

  30. #30
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    muddy pug by mbeganyi, on Flickr


    muddyvale by mbeganyi, on Flickr


    pugsley and mud by mbeganyi, on Flickr

    I'll have to stop and take a few snaps from the soggy soupy mess that has been cut up by boots and what look like cross tires back in the woods.


    I've been flattening out some 'regular' MTB ruts in the local woods. In some cases, and in certain types of terrain, I can see 'fat' being a far less damaging tire choice on sensitive trail.

    I really wanted some Nates this morning. A worn Endo in the rear was sliding around, and the Larry upfront can get pretty slippy.

  31. #31
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    Could we get a fat-tire trail groovyness study? Like does a trail get more groovy, when visited by fat-bikes?
    owner/raconteur at fat-bike.com

  32. #32
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    Riders locking their rear wheels when riding downhill can rip up vegetation and leave visible scars even when riding off-trail. The fact is that many disc brakes, especially the hydraulic variety, are too powerful and do not have the progressive control needed in order to prevent wheel lockout. Also some riders seem to think its clever to deliberately lock up their rear wheels.

    In wet and muddy Britain the subject of damaging well used trails is less contentious than damaging moorland and downland. This is because many trails are ancient and the worst of the erosion was caused centuries ago by the droving of livestock and the effects of horse and carriage. Some are so eroded that the lanes are now deeply sunken down to the bedrock. Or into the bedrock in the case of chalk

    Today on well used trails, after the horse riders, motorbikes, 4x4s, local deer and walkers have all churned up the mud the minimal effect of the bicycle wheels makes little or no difference. I do take the point about wheels creating erosion channels, but water mainly settles in the flat areas and dips, whilst slopes tend to drain naturally.

    Mudbike - The 1982 Cleland Aventura - YouTube

    Around here walkers are mainly concerned with cyclists riding too fast or not signaling their presence when approaching silently from behind. Walkers don't much like muddy conditions, but with such a wet climate there is little choice apart from careful route planning.

  33. #33
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    Quote Originally Posted by GrahamWallace View Post
    Riders locking their rear wheels when riding downhill can rip up vegetation and leave visible scars even when riding off-trail. The fact is that many RIDERS do not have the progressive control needed in order to prevent wheel lockout.
    Sorry, but it's nothing at all to do with the technology. I've used all sorts of hydraulic disk brakes, from the cheapest to some of the blingiest and they are all "progressive" enough for fine control.

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    Quote Originally Posted by druidh View Post
    Sorry, but it's nothing at all to do with the technology. I've used all sorts of hydraulic disk brakes, from the cheapest to some of the blingiest and they are all "progressive" enough for fine control.
    My idea of "progressive" braking is when the braking can be set to begin as soon as the brake lever moves and lockout occurs just before the lever touches the handle bar. The input/output ratio of any brake system could be designed to emulate this but its tricky because the difference in disk brake shoe position, between effective braking and locked out is so very small.

    I own six off-road bikes and only one of them fully meets this demanding criteria. This bike is fitted with cable activated, disk cooled, Shimano Roller Brakes. Inside they have a cam the shape of which precisely controls the leverage being applied to the rollers.

    To quote from derbyking.com: "Shimano Roller brake, one of the best modulated brakes of all times." Hayes 9 modulation is awful, though I am sure that there must be some well modulated hydraulic disk brakes around?

    There is a very long steep hill nearby with a dense line of bushes at the bottom, so no possibility of missing them if the bike builds up too much speed. I watch the local riders try to ride down this hill but they always chicken out. Like wise my friends have tried and decided that its to dangerous.

    Trail damage analysis for Fat Tires?-roller-brake-testing.jpg

    Despite never locking the wheels, I choose not to ride down this hill to frequently because of the damage I may be causing to the chalk downland grass. However the real advantage of using these brakes is their ability maintain control when descending steep muddy trails that are commonplace around here.

    The point is that well modulated brakes can reduce trail damage. But are fat tyres less likely to lockout than narrower ones?
    Last edited by GrahamWallace; 03-15-2012 at 10:33 AM.

  35. #35
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    Comparison - normal mtb, fatbike, footprint.

    The fatbike tread has flattened out a previous groove. The footprint and the other mtb are much deeper.



    Tracks that were liquid mud last month are now smooth and flat.
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  36. #36
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    Looking at the much bigger 'original' photo on flickr:

    The normal tire track to the left of your's looks deeper, but everything to the right of yours, including the footprints, looks to be the same depth or shallower. Meaning the mud depth is inconsistent across that section of the trail. Meaning there is no meaning to the depth of the tracks, compounded by the fact that noone knows the weight of the people who left the other tracks...

  37. #37
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    Good point.

    I think I'll make up an implement for measuring the gloopiness of mud.

    The surface in the middle there was much softer than the right hand bit with the shallower tracks.

    The footprint is mine. I was wanting to see how firm the surface was, so a footprint was used as a Gloopometer for comparison.
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  38. #38
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    I wonder what the trench(however shallow) we leave would look like if someone came out with a tire that was 'pinched' every foot of tread or so? So that externally, it would look like a lofty down jacket, only it wouldn't have the baffles. Would it flatten out enough to negate the pinches, or would it leave an interrupted trench that water couldn't flow down?

  39. #39
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    Or maybe something like this to confuse the ramblers...

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  40. #40
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    Quote Originally Posted by Velobike View Post
    Or maybe something like this to confuse the ramblers...
    This gives the term "lacing your wheels" a whole new meaning.

  41. #41
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    Here's a picture of myself (115 Kg) on the tephra ashes of Eyjafjallajökull (the Iceland volcano that blew its glacier top two years ago) on my Sandman Hoggar Ti fatbike with 3.8" Surly Larry tires inflated minimally - just 0.8 bar.



    The erratic tracks on the right were made by my friends riding regular bikes equipped with Schwalbe Fat Albert 2.35" tires. They weigh a lot less than I but they sank in very deep and had trouble staying their course.

    The "damage" is temporary because tephra ashes blow away like snow in a storm, but the picture demonstrates clearly the minimal impact, as well as the greater biking comfort.

    I even biked on the glacier itself, and over boulder fields full of volcanic glass (obsidian) without running a flat (regular bikes ran into trouble with both).

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