Viewing 22 posts - 1 through 22 (of 22 total)
  • 29er wheel obstacles
  • Premier Icon dyna-ti
    Free Member

    What height of obstacle with a 29er wheel easily ride over ?, as in without stopping dead or thereabouts.
    I’m kind of new to 29er and hitting lumpy rocks im just wondering what it will ride reasonably smoothly over as im more use to a 26″ . Fork is a 160mm.
    It’s all new to me and I’d rather not get pitched off.

    Premier Icon reeksy
    Free Member

    Erm… it depends on a fair number of variables – not just the size of the wheel but the force propelling it, the weight of the wheel, the surface type and traction.

    Trial and error.

    If you’re worried about getting pitched off, maybe MTB isn’t ready for you yet?

    Premier Icon intheborders
    Free Member

    You’ll know when it’s too big…

    Premier Icon nickjb
    Free Member

    Its pretty big. A lot will depend on where your weight is and what speed you have but if you are centred or back it’ll sail over some pretty large lumps. Try it, ideally somewhere safe. Ride at a log or set up a pile of pallets or bricks in the garden

    Premier Icon droplinked
    Full Member

    I don’t ride any differently between my 27.5 and 29er bikes. You just end up carrying a touch more speed.

    Still weight/unweight, brace for hits, lift the wheel etc, just the same.

    I never think “Oh I won’t bother bracing for that rock as I’m on a 29”.

    Premier Icon nickjb
    Free Member

    I never think “Oh I won’t bother bracing for that rock as I’m on a 29”.

    Probably not when barrelling down a hill but I might think that I’ll have a go at that rock step or see if I can get over that log.

    Premier Icon matt_outandabout
    Full Member

    Make sure measure those trail obstacles before your ride over them.

    Premier Icon cookeaa
    Full Member

    83.62mm exactly…

    Premier Icon DrP
    Full Member

    no.
    they’ve got a 160mm fork.
    so you can ride effortlessly over a 160mm obstacle.

    NEXT.

    DrP

    Premier Icon steve_b77
    Free Member

    Premier Icon dc1988
    Free Member

    All else being the same then yes it will ride a bit better over a given feature but there are so many other variables. A longer reach will put you more centred on the bike and make it less likely that you’ll go over the bars, a slacker head angle will also help. 29″ wheels will have more air volume in the tyres which will smooth the ride further.

    As others have said it is more about technique and body positioning that will stop OTB incidents

    Premier Icon dcwhite1984
    Free Member

    i dont think i hit any obstacles without at least unweighting the front first, maybe you should test it out and see, start with a kerb and work up to a 6ft wall and see how you get on.

    Premier Icon dyna-ti
    Free Member

    Erm… it depends on a fair number of variables – not just the size of the wheel but the force propelling it, the weight of the wheel, the surface type and traction.

    Trial and error.

    If you’re worried about getting pitched off, maybe MTB isn’t ready for you yet?

    Variables. Yeah guessed as much, and angle of terrain etc. Just an idea really. I think from experience about 150mm or thereabouts. but again depends. I just dont want to practice a run and get pitched off. and with the 26″ i usually pick my way through as opposed to riding over things. Slow and steady. Just seen too many yt vids of folk bombing through and always felt that would be more fun.

    As to getting pitched off, the last time it was a pretty bad injury and its knocked the confidence so much I sold all the bikes and stuff and it took a few years to get back into it. I just dont want to get injured again trying something thats beyond the limits of the bike due to inexperience.

    This is the ebike and its quite long and slack, so should be ok, just the experience is lacking.

    Premier Icon 5lab
    Free Member

    the wheel is approx 10% bigger so for the same angle of attack, 10% bigger obsticle than you’re used to.

    bigger wheels help a tad, but honestly its way more about technique.

    Premier Icon ayjaydoubleyou
    Free Member

    Applying some bro-science….

    take the centre of mass of the entrire system – this is very approximately going to be at your hips. MAybe a fraction lower on an Ebike as the bike is a bit heavier.

    drawa line from that CoM, down through the front hub (as this is what you will rotate around if the front wheel gets hung up) and continue that line until it meets the tyre. this will be the height of an obstacle that is the limit. any higher, your CoM will try to carry on, and the centre of rotation will be below it.

    A number of thigs will affect this:
    bike length, and where you sit on it. The further back your CoM is from the front axle, the slacker that imaginary line is, and therefore the further up the tyre it falls. Head angle, and a shorter stem is going to make most of the difference here, as most of the rest of the distance is going to be tied to your body size, assuming all bikes you ride fit you.

    wheel size, the bigger the wheel, the higher the hub, again, slackens the imaginary line and brings it further up the tyre.

    There are a couple of pitfalls though. This has assumed 1) no front forck compressing. as the fork compresses all that geo changes. As the fork isnt vertical, the axle not only goes up but also backwards
    and 2) that you, the rider, which must be 80% of the mass even on an ebike is completely rigid and does nothing to absorb the hit. Even if you didnt see the obstacle andhitting it surprised you, I doubt your wrists and elbows would keep you in place.

    And thats the biggest issue, its almost all about the rider. but bigger wheels and slacker head angles will help a bit…

    Premier Icon jacobyte
    Free Member

    I’ve just moved from a 26er to a 29er (both hardtails). 29er wins easily down my local rooty descents. It’s so much more enjoyable when you’re not picking yourself up off the floor all the time.

    Premier Icon andrewh
    Free Member

    nickjb
    Free Member

    I never think “Oh I won’t bother bracing for that rock as I’m on a 29”.

    Probably not when barrelling down a hill but I might think that I’ll have a go at that rock step or see if I can get over that log.

    This is true, ground clearance does appear to be better on my 29er compared to my old 26, fewer pedal strikes, bashed chainrings etc.
    Whether this is down to wheel size though who knows. It probably helps but then things like BB heights vary from bike to bike anyway, even with the same size wheels.

    Premier Icon kayak23
    Full Member

    I can clear a child up to about 4 years old on mine without pulling up.

    Premier Icon Northwind
    Full Member

    I don’t really think I’ve ever thought “I can ride over that more easily because of the wheel size” when looking at a single feature. I still have a 26 inch bike and I ride it pretty similarly. The difference is more about how all the bumps add up.

    Premier Icon i_scoff_cake
    Free Member

    At least two Insulate Britain protestors.

    Premier Icon Nobeerinthefridge
    Free Member

    Entirely down to the pilot, not the plane!

    Premier Icon sharkattack
    Full Member

    Just seen too many yt vids of folk bombing through and always felt that would be more fun.

    It’s not just more fun it’s the sensible thing to do. Don’t even think about the small lumpy stuff, your bike will fly over it anyway. Look ahead for the big stuff.

Viewing 22 posts - 1 through 22 (of 22 total)

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