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Paging biknben, others w/mtb smarts (followup to J's post)(12 posts)
|Paging biknben, others w/mtb smarts (followup to J's post)||TNSquared|
Jun 26, 2003 11:07 AM
|Why do I keep crashing?
Seriously, how does mtb setup/fit compare to road bike. My very sucky mtb skills aside, I don't feel comfortable with my position on the mtb and think it contributes to my multiple falls (twice in 10 miles yesterday.) I bought my mtb last Sept and have a total of maybe 12 rides on it, and only one this year which was yesterday with J, J2 and gang.
My road bike has quite a bit of drop and reach from saddle to bars, and the saddle is flat - no tilt.
After some tinkering today, my mtb is setup quite a bit differently. The saddle is at the same height as the bars. The reach is shorter than my road bike and the saddle nose is tilted slightly up. I also have the saddle slightly lower to the pedals.
In short, I've lowered my center of gravity and compressed my length so that I'm sitting more upright with my weight on my butt. Somehow, this seems to make me more balanced on downhills and hairpin turns.
Am I headed in the right direction?
Vertically Challenged Todd
|How are you falling?||Dwayne Barry|
Jun 26, 2003 11:13 AM
|If you're taking headers you're braking too much and not maintaining enough momentum to clear obstacles. If you're sliding out in the corners, you might be leaning the bike too much (typically how roadies corner). On a mountain bike you want to try to keep the bike as upright as possible and lean your body when cornering or if slow enough turn the front wheel rather than counter-steering. Same is true for off-camber stuff where you might lose grip, keep the bike up-right.
And finally, crashing is part of mountain biking. If you don't are you really going as fast as you could be?
|Slow and ugly - no style points at all :)||TNSquared|
Jun 26, 2003 12:19 PM
|I do brake too much (and too hard), but no headers or problems clearing obstacles on flats and uphills. I actually enjoy root laden climbs.
I have lots of trouble with sharp hairpin turns. By slowing enough to make the angle, I feel like I can't steer the turn. I think you hit the nail on the head that I'm trying to turn like a roadie.
I also dread any steep, short descent/ascent combination. Memphis trails seem to have a lot of these, almost like oversived drainage culverts. Even when I hang my rear off the back of the saddle going into the descent, I feel like I'm too far forward and about to go over the bars. Then I hit the ascent with my weight still back, and the front tire is in the air.
In both situations, I usually end up falling to one side or the other. My balance sucks, which is what made me think my position on the bike is not correct. I'll work on the turning technique, sounds like that will help with my first problem.
Any suggestions for the second problem?
I realize crashing is part of it, but somehow I don't think I should be spending more time splayed across the trail than in the saddle. (BTW - my skiing nickname is Yard Sale.)
|Drainage ditches are tough...||biknben|
Jun 26, 2003 12:45 PM
|They require a quick transition of weight from back to front. They are all different so it is hard to pinpoint axactly what to do.
Think about this solution. As you get to the bottom, with your weight back, attempt to pull a wheely. This will thrust your weight forward for the uphill portion and unweight your front wheel so it doesn't get hung up at the bottom.
|Slow and ugly - no style points at all :)||Triphop|
Jun 26, 2003 2:00 PM
|Hairpins can be difficult, especially when a water bar is thrown in. I assume your trouble is on the descent? The technique that gets me through best is to lean the bike into the turn, but keep my body upright, and keep my weight centered front to back.
As for the steep downs into quick ups...you are starting out well off the back of the saddle, but when you reach the transition into the flat, move your weight forward, and let the bike roll underneath you, in the middle of the flat you should be centered over the bike, so when you hit the next transition uphill, your weight is not over the front wheel, let the bike roll up under you, then as you begin to rise up the other side, you can move your weight forward and pedal.
I just saw your comment about feeling like you aren't far enough back, if you lower your seat that may help, but if it is really steep, you just got to hang on, otherwise you will end up with tread in your rear. This kind of riding sounds like what I used to ride in Illinois, since these descents are steep and short, just hang on until you reach the bottom, chances are you are back far enough.
Oh, most importantly, relax!
I hope that helps some.
|That's a tough "ditch"||SpecialTater|
Jun 26, 2003 7:52 PM
|especially on the first run through. I misjudged it too.
The number one thing I've learned for trail riding over obstacles like the ditch is speed rules. (I know I'm one to talk...I fell on the easiest part of the trail...) It's tough to have enough confidence to go fast through some of that stuff but the momentum created by speed gives you a higher margin of error. It doesn't seem logical and it takes a denial of your self-preservation instinct, but it helped me tremendously when I was riding a lot in Georgia.
Personally I think some of those turns they've put out there do not make for a good MTB trail. There's not enough flow from one corner to another and many of them don't make sense to me or they are just too sharp. Just my opinion. J2 seems to like them, but the other trail we know seems SO much better.
Good luck in the race. Let me know if you want a partner in suffering again next week.
|Slow and ugly - no style points at all :)||pawistik|
Jun 27, 2003 1:48 PM
|Did this the other day going through a deep (20') drainage ditch with a v bottom. My weight was back for the descent and I was a bit slow bringing forward for the ascent. I ended up going over backwards & landing on my back in slow motion. A very smooth landing though!|
|I didn't see the second biff||JS Haiku Shop|
Jun 26, 2003 12:02 PM
|but that first one was caused by your left hand.
on the mtb when crossing deep dry streams like that one (with logs & stuff in the middle for "traction"), get yer rear over the back wheel as/after you cross the lip of the creekbed, don't even think about using the front brake, and use the rear only to "modulate" speed--not to stop. you want to carry as much momentum as possible through the gulf of that crossing, so you can get up the other side.
keeping the front wheel light and using flexy elbows helps to get over those obstacles in the creek bed.
giving a little umph with the engine coming out of the crossing helps stay upgright and continue momentum.
you might have noticed J2 go directly from trail to crossing back to trail without any hesitation. two things came into play there: experience, and ultra-low IQ. of course i'm working on my smarts, so i of course pulled up to look at that crossing and sweat a little. but, once you start riding more with J2, you'll learn that either you do it, crash, go back and do it again until you get it right, or walk it, and listen to his "good-natured ribbing" for the next forty-two years.
did you walk the rock garden that second lap around?
I didn't see your second grav-check.
sounds like you've got your bike setup more appropriately now for mtb riding, especially technical/tight/slow stuff. i had flipped my stem to a negative (downward) angle and lowered the seat, and removed the bar-ends for that first 'cross race last year, and i paid the price for it last night. my stem will be flipped back to a 2-3" higher position (closer to saddle height) and the rest setup as appropriate for this particular trail.
more than anything else, dirt time will help you become more proficient and able as your confidence grows.
crashing sucks. i purposely didn't spend much on my mtb 'cause (1) i dont' mtb much, and (2) when i do, i trash the bike (and rider) against mother nature. it's mostly stupid risks, but sometimes it's lack of confidence, but committing anyway.
|My left hand is stronger from all the work it gets..||TNSquared|
Jun 26, 2003 12:37 PM
|cracking that snare drum!
Yeah, I hit the front brakes, prompted mostly by the small tree that jumped in front of me as I started into the crossing. (Picking a good line is not one of my strengths, either.) Still, felt like I should have been able to save it if I had one iota of skill.
I traversed the rock garden "no hay problema" on the second lap. More than anything, it just caught me offguard the first time coming around that blind corner.
Second bail out/biff was even dumber than the first. Found my bars headed for a tree on one side or the other as I flopped through a hairpin.
I think my failing as a mtb rider comes from an overly intense self-preservation instinct.
|Don't sweat it...||biknben|
Jun 26, 2003 12:39 PM
|Your "position" is certainly contributing to the falls but not the way you think it is. The setup you describe is typical for most MTB riders. A shorter TT and higher bars is the way to start. This puts your weight further back and increases stability. Although I keep all my saddle heights the same, lowering the seat allows you to move back off the saddle easier when you need to.
The bike fit will determine your position when you are just pedaling along. That's great when you are riding on smooth, flat hardpack. More than likely, the terrain is constantly changing and your position has to change with it. Weight distribution or body position is key. As you approach an obstacle or significant variation in conditions you have to distrubute your weight in advance. A lack of proper postioning is what leads to lose of control.
This is most likely a matter of experience. As you ride more you will find what works for you.
-When approaching a tight turn, move forward onto the nose of your saddle. This will increase traction at the front wheel. Watch a motocross rider take a tight turn. They sit on their tanks as they hit the turn.
-If approaching an obstacle, you move back and unweight the front wheel to absorb any impact. The less impact you absorb, the more the bike slows down. If the bike slows down too much, you are going over the bars. This is a factor in most crashes.
-Up a technical climb? Jam the nose of the saddle up your butt. Literally!!! This moves your weight forward and keeps your front wheel on the ground. At the same time, you maintain traction at the rear tire because your butts still in the saddle.
If you are moving at a good clip you should be moving around constantly preparing for all types of terrain variations and obstacles. The fit of the bike plays a smaller role.
|It depends on the type of mtbing you do||Atombomber|
Jun 26, 2003 6:26 PM
|I have 3 mountain bikes.
XC bike has saddle such that I have the same leg extension as on the road bike. The bars are even with the saddle.
Freeride bike has the option to lower the saddle for descending. For climbing, it is the same as my XC bike, but I can lower it about 6 inches. The wider bars are about 1 inch higher than the saddle at the highest.
DH bike has a really low saddle and high wide bars. Saddle is about 8 inches lower than the XC bike, and the bars are about 9 inches higher than the saddle.
|re: Paging biknben, others w/mtb smarts (followup to J's post)||Mazinger|
Jun 27, 2003 5:03 AM
|When I'm on a MTB I don't put as much weight on the front tire as I would on a road bike. You just have to be very light on the front tires.
As far as sharp turns. Try to stay straight up. Don't try to lean on the turns.