Mountain Biking - #%@*! Tree Roots

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View Full Version : #%@*! Tree Roots


indygreg
05-05-08, 06:03 PM
Okay, so I am fairly new to the MTB thing (a roadie at heart). I will always be somewhat limited by fear (just my nature) so it is not like I am bombing through the local trail at top speeds . . . but I am a decent rider and somewhat strong so I get around okay.

What is the deal with tree roots? I have had several near wrecks with them and today I went down hard. As in around a turn with tree roots slanting down (like opposite of a banked turn). Front tire slides out and down I go. I am fine, bike is fine, but these damn roots. Not wet or anything.

I know only practice makes me better - but any tips on roots? I ride with a guy that has little to no cycling experience and he goes over them like they are not there. Our tires are plenty similar . . . bike are both hardtails - mine a decent bit lighter but maybe a higher flex shock, our weight is similar and we ride about the same speed.


urban_rider64
05-05-08, 06:10 PM
I don't do much trail riding, but a friend who's a pretty decent XC rider told me when we went out on a local trail to remember to ride over the root with you tire perpendicular. Sounds like in your case, that wont quite work, but maybe if you go a little wider where there's less root, you can get through. Next time let him go ahead of you and watch what line he takes over them.

mtnbiker66
05-05-08, 06:58 PM
A little wider means singletrack become doubletrack. Speed is your friend, it will help you get through the roots without hanging up. If it's a section thats not too long, you can use the first root to boost over the whole section......
http://i173.photobucket.com/albums/w69/mtnbiker66/Bikes/Dupont07026.jpg


indygreg
05-05-08, 07:03 PM
in areas like that I am golden. You are right, speed is your friend.

This crash area and other areas where I have nearly crashed are harder turns with roots canting down away from the turn. One root is fine . . . sort of unweight and the back tire will slide a bit on it and all is good. This section has about 10 over maybe 2 feet in the turn. The turn is such that I cannot unweight the front over all the roots as I would go through the turn. Plus if I do not unweight far enough, I come down on a root with even more weight and leverage in a turn.

I just took it too fast today . . . at least until I get better at it. I think I lean the bike too much with me too much on top of that. I think there is some trick to leaning the bike but using the body in a bit of a counter movement to keep COG more upright. I will figure it out or get beat up.

Lebowski
05-05-08, 07:12 PM
i turn my front tire towards the root. i grip the bars hard and tense my arms but i don't lock my elbows. roots haven't been a problem. just don't rub up against them, you'll tip over.

mtnbiker66
05-05-08, 07:13 PM
Practice grasshopper, you will master you foe.......

crtreedude
05-05-08, 07:16 PM
you might be able to hop them.

M_S
05-05-08, 07:35 PM
Might be a stupid question, but what tire pressure are you running?

Cannondaler
05-05-08, 07:47 PM
Might be a stupid question, but what tire pressure are you running?

Not a stupid question, that's the first thing I thought. Pressure could be too high.

deraltekluge
05-05-08, 07:56 PM
I think there is some trick to leaning the bike but using the body in a bit of a counter movement to keep COG more upright. I will figure it out or get beat up.The side-to-side position of your center of gravity relative to your tires' contact patches is determined by your speed and the radius of your turn. Nothing else you do affects it. You can make the bike's frame and wheels be more upright or less upright, but the position of your and your bike's over-all center of gravity is unchanged. The resultant vector of your weight and your cornering force must intersect the line through the tires' contact patches, or you'll fall over.

indygreg
05-05-08, 08:07 PM
Might be a stupid question, but what tire pressure are you running?

I just got new tires - Kenda Nevegals in a 2.1 width. I think they call for pressure of 40-65PSI and for the maiden voyage I split the difference at 50.

pyroguy_3
05-05-08, 08:14 PM
Might be a little high, but it's your ride. I keep my Hutchinsons at a point where it looks like it's "flat", but still not flat. Hard to explain as I don't have a gauge. You can always try a little less pressure and if it doesn't bode well, jack them back up with your frame pump.

indygreg
05-05-08, 08:17 PM
I will try lower pressure for sure next time. This is a part of being a roadie I am sure . . . anything less then 110psi feels flat. ;)

I will go 40 and see what I think. This is all part of the fun - try new things. Different tire pressures. Different shock air pressures, etc.

Cannondaler
05-05-08, 08:29 PM
The trails I ride regularly ar loaded with roots. I weigh 210lbs and I run 45psi front and rear and it seems to work well for me.

DirtPedalerB
05-05-08, 08:37 PM
Usually a lower pressure in the front is what I run .. my tires say 40 - 60 I run 35-40 in the front and 40-45 in the rear.. also a larger front tire. Try turing the bars more toward the root right as you hit it ... the worst that can happen is the front gets over and your rear tire buzzes down the root...

indygreg
05-05-08, 08:40 PM
Usually a lower pressure in the front is what I run .. my tires say 40 - 60 I run 35-40 in the front and 40-45 in the rear.. also a larger front tire. Try turing the bars more toward the root right as you hit it ... the worst that can happen is the front gets over and your rear tire buzzes down the root...

Actually, my result was much worse than your worst that can happen. Some cuts, bruises and the wind knocked out of me . . .and some laughter by me.

In all seriousness - thanks for the advice. I went from a 1.95 to a 2.10 on front and back to go wider. How many folks ride a 2.3+ on the front?

ZeCanon
05-05-08, 09:12 PM
I run 24psi front and 26psi rear... that's tubeless of course, so I don't have to worry about pinch flatting, but you should be able to get down into the 30's. You will be amazed at how much better your traction is (and how much more comfortable you are!)

indygreg
05-05-08, 09:15 PM
I have considered going tubeless on my MTB . . . just not sure. Partially because I would want to get a second set of rims as I put on semi-slicks for urban riding a decent amount. I would think that kink of pressure would yield a lot of traction!

I am going to lower my and see what happens.

mx_599
05-05-08, 10:28 PM
Okay, so I am fairly new to the MTB thing (a roadie at heart). I will always be somewhat limited by fear (just my nature) so it is not like I am bombing through the local trail at top speeds . . . but I am a decent rider and somewhat strong so I get around okay.

What is the deal with tree roots? I have had several near wrecks with them and today I went down hard. As in around a turn with tree roots slanting down (like opposite of a banked turn). Front tire slides out and down I go. I am fine, bike is fine, but these damn roots. Not wet or anything.

I know only practice makes me better - but any tips on roots? I ride with a guy that has little to no cycling experience and he goes over them like they are not there. Our tires are plenty similar . . . bike are both hardtails - mine a decent bit lighter but maybe a higher flex shock, our weight is similar and we ride about the same speed.
just pedal faster!

mx_599
05-05-08, 10:29 PM
I have considered going tubeless on my MTB . . . just not sure. Partially because I would want to get a second set of rims as I put on semi-slicks for urban riding a decent amount. I would think that kink of pressure would yield a lot of traction!

I am going to lower my and see what happens.

tubeless aren't all they're cracked up to be...and this time i am not joking around

mx

pinkrobe
05-05-08, 11:04 PM
Actually, my result was much worse than your worst that can happen. Some cuts, bruises and the wind knocked out of me . . .and some laughter by me.

In all seriousness - thanks for the advice. I went from a 1.95 to a 2.10 on front and back to go wider. How many folks ride a 2.3+ on the front?

I hear ya on the whole roadie "max pressure" thing. On the road I run 120+ psi for commuting and long rides. On the mtn bikes, I rarely exceed 40 psi, especially since most good-quality tires have some sort of anti-snakebite feature. I ride with a 2.3 in the front and rear on the full-suspension bike, and 2.3 front/2.1 rear on the rigid SS. The wider tread makes a surprisingly big difference to cornering, especially on looser dirt, roots and scree. For a hardtail, I would not hesitate to run a 2.3 in the front to enhance traction.

M_S
05-05-08, 11:20 PM
Like others have said, try lowering your pressure for sure. It depends ona lot fo factors of course, but I'd be running in the low 30s in front, or lower, and maybe mid 30s in back My rule for off-road riding tends to be to run the absolute lowest pressure I think I can get away with.

My problem was the opposite of yours. A few years ago when I started riding road after having been mostly into mountain biking I thought 70-80 PSI was ridiculously high, and kept wondering why I was getting pinch flats.

Terrapin Ben
05-05-08, 11:45 PM
I've heard Tinker Juarez runs his tires at 65 or 70 psi. Something rediculous. Differnt strokes for different folks I suppose. Most likely Tinker is just a whole different breed of animal.

Chris_F
05-06-08, 06:44 AM
Practice makes perfect here. It takes a little experience to learn what your tires are going to do when they hit different roots at different angles. It's usually a good idea to take roots as perpendicular as possible, but when that isn't an option then being read for what the bike will do is a good thing.

bac
05-06-08, 06:54 AM
The bottom line is that riding technical stuff requires practice and some skill. You'll get better over time. The times you crash will work as negative reinforcement so you will not make the same mistake twice. Don't ask me how I know. :D

Good luck!

... Brad

ZeCanon
05-06-08, 06:57 AM
tubeless aren't all they're cracked up to be...and this time i am not joking around

mx

For cross country, yes they are. I'm not talking full UST setups, as those are exceptionally heavy, but a ghetto stans sealant setup with standard tires drops 1/4 lb from your wheels, eliminates pinch flats, pretty much eliminates punctures, allows you to run lower pressures, decreases rolling resistance, increases traction... the list goes on and on.
Not all they're cracked up to be? Right... Those are the words of someone who has never used tubeless, or never figured out how to reap the benefits of it. I would personally never go back to tubed tires for racing, and try to avoid tubes as much as possible during general riding as well. When you get used to 25psi, you get spoiled, and anything over 30 feels like you're riding on blocks of wood. 25psi w/tubes, in colorado, = instant pinch flat.

junkyard
05-06-08, 11:16 AM
I have read a lot of good responses. I think that many will help with the root situation. Overall, though, I think you are just overthinking it. Keep up the momentum and just stop thinking. You will glide over them. The only times I really put thought into how I'm going to handle a root is on a steep uphill with a root that is neither parallel nor perpendicular to the trail. With the lack of momentum and constant shifting of weight, these will pose problems. Otherwise, I try not to overthink.

chucko58
05-06-08, 11:39 AM
My bike takes big wide tires - I'm running Kenda Cortez 2.4s. The sidewall says 40-60 PSI, but I'm finding that 40 PSI front is a bit high, and I'm usually comfortable with 44-46 rear, even though I'm a Clydesdale (205 lbs before riding gear, probably 225 with everything). I suspect the pressure ratings are conservative on the low end.

I prefer to feel the tires give a bit in the dirt. Knock on tree roots, I have yet to get a pinch flat in 15+ years of MTB riding. The tubeless guys run pressures so low it's a miracle the sidewalls hold up.

RIC0
05-06-08, 01:49 PM
Stay light on your toes so you can easily take the pressure off the front end if need be. Tire pressure isn't going to do squat besides give you a pinch flat if it's too low, it's just one of those trail obstacles that you'll have to learn to manuveur on or around.

mx_599
05-06-08, 04:29 PM
For cross country, yes they are. I'm not talking full UST setups, as those are exceptionally heavy, but a ghetto stans sealant setup with standard tires drops 1/4 lb from your wheels, eliminates pinch flats, pretty much eliminates punctures, allows you to run lower pressures, decreases rolling resistance, increases traction... the list goes on and on.
Not all they're cracked up to be? Right... Those are the words of someone who has never used tubeless, or never figured out how to reap the benefits of it. I would personally never go back to tubed tires for racing, and try to avoid tubes as much as possible during general riding as well. When you get used to 25psi, you get spoiled, and anything over 30 feels like you're riding on blocks of wood. 25psi w/tubes, in colorado, = instant pinch flat.

you don't have to jump down my throat. i wasn't talking about DIY tubeless/conversions. ust set-ups have heavy tires!

i use low pressure in tubes with stans. i have been running 25-30, sometimes less.

mx

heckler
05-06-08, 05:01 PM
I run at 60 psi (40-65 range) 2.1s front and back (which is apparently high compared to you guys) and never have problems with roots unless it is wet. I undrstand that lower pressure will aford you better tractions, but don't you sacrifice speed?

btw I HATE pinch flats and don't mind taking a beating so 60 psi seems to work for me, but with all the lower pressures on this thread I might try something like 45-50 this weekend.

I used to get the front over them the rear would ride down the angled root, since then I have gotten better about feeling the rear tire start to slide and hopping the back up.

never
05-06-08, 05:48 PM
I undrstand that lower pressure will aford you better tractions, but don't you sacrifice speed?


It'll depend on the type of trail but generally lower pressures do not hurt speed for off-road applications. If the pressure is too high, the tires will hit trail bumps, etc. which will kill speed. Lower pressure tires will roll more smoothly over the same bumps thereby maintaining speed.

roccobike
05-06-08, 09:01 PM
I just got new tires - Kenda Nevegals in a 2.1 width. I think they call for pressure of 40-65PSI and for the maiden voyage I split the difference at 50.

I tried 75PSI.......Once......bounced all over like a que ball that was hit very hard. I run the bare minimum pressure on single track rides. On my road bike or when I ride my MTB on a MUP, I run the maximum pressure.

mx_599
05-06-08, 11:22 PM
how low can you go?

http://previews2.nvtech.com/100/tf05039/NVTech_cart0770.jpg

Feathers
05-06-08, 11:28 PM
too much tire pressure results in tire losing contact with ground via vertical travel.
lower the pressure down to the 40 p.s.i. range and you'll be faster than before with greater traction.

Fat Boy
05-07-08, 09:40 AM
Most likely Tinker is just a whole different breed of animal.

Truer words are rarely spoken.

Cheeto
05-07-08, 05:51 PM
In mountain biking tire pressures are generally low.
I was running 40 and was told it was to high.
Im at about 32 and 35 psi now.
seems to work ok.

try not to lean so much on the turns also, maybe you're riding on the sidewall fo your tire

DirtPedalerB
05-07-08, 06:21 PM
well you bought a light bike, now your wanting to slam a 2.3 brick on the front of it?? maybe soften up the fork some before adding a masher.

rankin116
05-07-08, 06:31 PM
try not to lean so much on the turns also, maybe you're riding on the sidewall fo your tire

On the sidewall? Really?