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  1. #1
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    Why do I keep crashing?

    Hi All,

    I recently bought a Kona Hei-Hei 29" full-suspension. I went with 29" because lots of folks around where I live are riding them. However, I've recently had a couple of bad spills (5 stitches in elbow; 3 broken ribs; road rash best measured in ft^2) that for the first time in my riding life I can't really explain. And I've never really crashed this often before. Terrain wasn't technical. Best I can describe is that my front wheel just kind of went where it wanted to, flipping me over the bars head first both times. I was thinking that this might be related to lateral rigidity, in which case the torsion on the wheel/fork got to the point that it just overtook my bar control. I'm wondering: is rigidity (or lack thereof) a sensible explanation? If so, what can I do to help fix it? Different wheel set? Forks? Stem length?

    Here's what I'm running:

    • WTB SX23 29" rims with QR
    • RockShox XC 32 TK 100mm
    • Kona stem - 90mm (not sure of the angle)



    Thanks for any and all thoughts!

  2. #2
    Formerly of Kent
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    Literally none of the things you listed are what come to mind.

    How about:

    Tire selection
    Tire air pressure (tubeless?)
    Fork pressure

  3. #3
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    Didn't feel like a traction issue (wheel didn't slide, but riding with Tioga Psycho Genius 2.25 with tube at ~ 32psi). Fork pressure was 95-100, and I weigh 155lb. How might fork pressure explain?

  4. #4
    It ain't easy being Green
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    OTB crashes are typically cause by too much forward weight transfer happening too quickly; there are a many potential causes, here are a couple to look at:
    1. If you still have your old bike, measure from the tip of the saddle to the stem/bar interface; repeat on your new bike. Significant difference?
    2. Are your new brakes more powerful than your old ones? Many OTB crashes are caused by poor brake discipline; particularly when a ride suddenly acquires new hydraulics that actually work.

    Anyway, try getting your butt way back in the saddle on descents and don't "death grip" the front brake; if your front wheel stops rotating and your weight is too far forward you'll get pogo'd OTB every time.

  5. #5
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    Thanks for the tip. I'll check out suggestion #1. I'm pretty good about keeping my weight back (lessons from experience, Colorado, 1999), my new brakes actually aren't as good as my old ones, and, as I recall, I wasn't even braking for crash #2.

    I was thinking a shorter stem would help, but I'm not sure how that would affect handling?

  6. #6
    West Chester, PA
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    Maybe slow down a bit until you get used to the new bike?

    Or, maybe its just a bad stretch. Bad crashes come in bundles for me. I might go years without hitting the deck hard, but when I do it's usually a few in a row. I have some significant scarring from summer 2011. But nothing since except some minor scrapes.

  7. #7
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    A shorter stem isn't bad for handling, just a bit different so takes a bit of getting used to. The only thing to really mind is that you don't make the cockpit too short.

  8. #8
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    Here's something else to check. I ride hard tail and had a couple unusual crashes. Turned out to be my rear wheel was not fully tightened and would move slightly under pressure. This upset steering balance enough to cause the falls, without warning or noticeable cause. For fs I would also check all suspension points for any slop..

  9. #9
    Fat-tired Roadie
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    Is your riding position different from on your previous bike?
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  10. #10
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    Lots of good suggestions here. Tire pressure was my first thought; I've found that I need lower pressure with my 29er than I did with my 26er. Fork pressure, too - and also compression damping if you can adjust that. Years ago I did an OTB on my first ride with a new fork because it compressed so much deeper into its travel on a trail I was very familiar with. I was used to keeping my weight back, but it wasn't enough because the fork behaved differently; it just took some more rides to get used to it. So you may need more compression damping, or maybe more air pressure. (My wife had a similar experience with a new fork; I needed to adjust air pressure and compression damping.)

    One other things that might put your weight farther forward - are your handlebars lower (farther below your saddle) than on your old bike?

    Also, I do find it pretty common to crash with a new bike, even when things are well adjusted. Maybe it's just that body position isn't quite the same, and it takes a while to adjust. I think it's a good idea to ride a bit more conservatively until you get a good feel for the new bike.

  11. #11
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    Personally Im leaning on its a completely new bike. 26 going up to 29er put me otb at least once on each of the trails I know around here, same instance as you, front went where it wanted it seemed and down I went. Got used to the new bike and was better and then started paying attention to how bike reacted to what. Did it at a bit slower speeds and then higher speeds (sections where minimal trees and plenty of grass if I went down) to learn the bike. Error on the the side of riding slower then you normally would and pay attention to the bike and adjust your riding technique, few rides later youll be back to riding your normal speeds and not even realize it. 26" riding habits cause pain when you expect a 29er to do it the same. Also adjust stem/bar height and maybe lengths slightly for more/less response as you feel is needed. Remember 29er as more leverage against your input on the bars thus can overcome you more easily, learn and adjust accordingly.
    Trek Marlin 29er

    Like It, Love It, Want Some More Of It!

  12. #12
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    Thanks, these are all good suggestions. Enough to think about while I wait for bones to mend.

  13. #13
    Carbon & Ti rule
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    I just about never crash, Twice in the Last 3 years, (only times I have been over the bars in 3 years ) I have had a day that I have gone over the bars twice in 1 day.

    So over the bars 4 times total & every time it was on a bike with a much lesser dollar fork than my good bikes.

    A real good fork may not stop all your crashes, but man I have lost count of how many times a very good fork has saved my but.

  14. #14
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    In a nutshell:

    A 26er goes where you want, a 29er goes where you are looking.

    Just about 100% of my 29 crashes end up being right into the hazard I was staring at.

    You need to force yourself to look PAST the gap in the rocks, the downed tree, whatever. Just like when you first learned how to drive a car.

  15. #15
    JHH
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    The only thing I can add is Stem height......Is your stem still stacked with spacers above the headtube? I was having handling issues that lead to a few moments and a crash until I got this sorted on my bike and lowered my stem to sit on a single 2mm spacer. THis lowered my weight distribution over my front tire and now I feel much more confident cornering.

  16. #16
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    Quote Originally Posted by JHH View Post
    The only thing I can add is Stem height......Is your stem still stacked with spacers above the headtube? I was having handling issues that lead to a few moments and a crash until I got this sorted on my bike and lowered my stem to sit on a single 2mm spacer. THis lowered my weight distribution over my front tire and now I feel much more confident cornering.
    There are heaps of spacers. How did you know how low to go? Trial and error before cutting? This bike also has a longer stem (90mm) than my last (60mm). I don't really like being so far over the bars, so maybe I should just go for a shorter stem?

  17. #17
    offroader
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    1) Slow Down
    2) Learn to ride
    3) Know your limits
    4) Rinse and repeat

  18. #18
    JHH
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    Quote Originally Posted by djap View Post
    There are heaps of spacers. How did you know how low to go? Trial and error before cutting? This bike also has a longer stem (90mm) than my last (60mm). I don't really like being so far over the bars, so maybe I should just go for a shorter stem?
    I ride a 100mm stem I've got long arms. Riding position is completely personal. I knew from previous bikes that my hands liked to be lower than the nose of my seat when pedaling up hills (dorpper post changed the game on that one on descents) And I could tell taking tighter corners that my hands and body felt high in position thru a corner. In off camber corners I could really feel that I wasn't getting the pressure loaded the way I needed to. So I started lowering the stem. 29'rs headtubes are taller than a 26" so I knew there was room to drop the stem height. I began taking out half the height. Handling improved. I dropped it all the way no spacers, but I started getting some wrist/hand pain. I bumped it up 5mm felt to high. went down to 2mm AHH just right. Bike handles as I expect and no wrist/hand issues. It may seem like small movements but if your looking for answers small changes often have biggest effects. And with body dynamics in cycling it's small incremental changes that can have the biggest impact on performance.

    I cut down the steer tubeion the fork only when I found the final riding position. I also left about 5mm of spaces on the top just in case I need to go higher and that why don't have to buy a new fork.

  19. #19
    1*14*29*2.1 & 1*1*29*2.4
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    Quote Originally Posted by squareback View Post
    In a nutshell:

    A 26er goes where you want, a 29er goes where you are looking.

    Just about 100% of my 29 crashes end up being right into the hazard I was staring at.

    You need to force yourself to look PAST the gap in the rocks, the downed tree, whatever. Just like when you first learned how to drive a car.
    This is what I was thinking....when you say your front wheel just went where it wanted to, do you mean you couldn't change your line or change your mind? My sus fork Ht is a lot more like that than my rigid ht. There are things you can do to help but it's more about adapting to your new bike and thinking ahead. Your bike will quite possibly roll over a lot of stuff better than a more "nimble" bike so you may need to think of that instead of weaving through stuff at the last minute.

  20. #20
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    Quote Originally Posted by finch2 View Post
    This is what I was thinking....when you say your front wheel just went where it wanted to, do you mean you couldn't change your line or change your mind? My sus fork Ht is a lot more like that than my rigid ht. There are things you can do to help but it's more about adapting to your new bike and thinking ahead. Your bike will quite possibly roll over a lot of stuff better than a more "nimble" bike so you may need to think of that instead of weaving through stuff at the last minute.
    I've been riding bikes all my life, and mt bikes for about 16 years, and this experience is new to me (which probably points to the 29" and a new cockpit geometry, since I haven't had this problem on other 26s), but by the front wheel going where it wanted to, I meant that I had a straight line and the wheel overtook me, once turning left, once turning right, and in both cases putting me OTB. I've had similar loss of control when I've hit a root, or small stump that was sticking out of the trail deflecting the wheel, but here there wasn't anything obvious on the trail.

    I'm going to try out a much shorter stem and play with the bar height, see if that helps anything. Of course, getting used to the limits of the bike will help too. Thanks for your thoughts.

  21. #21
    1*14*29*2.1 & 1*1*29*2.4
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    Quote Originally Posted by djap View Post
    I've been riding bikes all my life, and mt bikes for about 16 years, and this experience is new to me (which probably points to the 29" and a new cockpit geometry, since I haven't had this problem on other 26s), but by the front wheel going where it wanted to, I meant that I had a straight line and the wheel overtook me, once turning left, once turning right, and in both cases putting me OTB. I've had similar loss of control when I've hit a root, or small stump that was sticking out of the trail deflecting the wheel, but here there wasn't anything obvious on the trail.

    I'm going to try out a much shorter stem and play with the bar height, see if that helps anything. Maybe I should've gone with an AM rather than a XC, since that's how I like to ride. I just thought that I'd get more function with a XC given my local trails.
    OK, doesn't sound like what I thought....but I can't think of why you are having this issue if it isn't a malfunction. Keeping a line is one of the best things about a 29er. Have you checked spoke tension on both wheels? Sometimes new wheels can get loose, and this will affect rigidity a lot. You could possibly lower your pressure to 25 max IMO but I wouldn't think this in itself would cause the amount of grief you have had.

  22. #22
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    Quote Originally Posted by finch2 View Post
    OK, doesn't sound like what I thought....but I can't think of why you are having this issue if it isn't a malfunction. Keeping a line is one of the best things about a 29er. Have you checked spoke tension on both wheels? Sometimes new wheels can get loose, and this will affect rigidity a lot. You could possibly lower your pressure to 25 max IMO but I wouldn't think this in itself would cause the amount of grief you have had.
    I can't either, which is why I posted this. Spokes loosened a LOT after my first few rides, so now I've got this situation where some sections are very tight on one side, but nothing flimsy. I thought maybe rigidity of the fork. One person in another post suggested that the 9mm axle could be a contributor. Possibly. I also may just be overthinking this because broken ribs suck, 6 weeks for a gashed elbow to heal sucks, and I wish to hell there was a way to avoid repeating them. In any case, I have a pretty sweet scar now that looks like a flaming meteor shooting out of the sky.

  23. #23
    1*14*29*2.1 & 1*1*29*2.4
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    on paper I can't see why you are having the issues. I have always used 9mm hubs and have a reba 07 on my ht. Never have the issues you have. I even have a steeper HA of 71.5 deg on that bike. I washed out and broke my ribs too....that was my fault daydreaming in the middle of a fast run. I know how you feel, it really sucks. Maybe you are just going way too fast on the 29er If your bike is particularly vague in steering I can imagine you could have some issues but I can't see why it would be. Have you tried any other 29ers to compare?

  24. #24
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    Short and Simple:

    A 29er is going to feel and perform differently and a learning curve is neccasary.

    Advice:

    Take your time.
    Slow down and wait until you are comfortbale.

    Results:

    When I ride my 26er I hate it becuase it feels awkward.

  25. #25
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    Quote Originally Posted by djap View Post
    I've been riding bikes all my life, and mt bikes for about 16 years, and this experience is new to me (which probably points to the 29" and a new cockpit geometry, since I haven't had this problem on other 26s), but by the front wheel going where it wanted to, I meant that I had a straight line and the wheel overtook me, once turning left, once turning right, and in both cases putting me OTB. I've had similar loss of control when I've hit a root, or small stump that was sticking out of the trail deflecting the wheel, but here there wasn't anything obvious on the trail.

    I'm going to try out a much shorter stem and play with the bar height, see if that helps anything. Of course, getting used to the limits of the bike will help too. Thanks for your thoughts.
    See if you can get the same tire in a 29er that you had on the 26er. I know I hated the stock tires on my new bike, horrible traction. They lasted one ride.
    13 Lenz Lunchbox punkass

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