- Does suspension cause stutter bumps?
The only thing I would add to this is that the aforementioned mincers' bikes let the mincers ride down things they might not otherwise have tried, and their lack of skills then means muchos skidding and braking bumps.
So in a way it's the bike, but mostly it's the mincers.Posted 7 years agoglenpMember
Braking. Suspension might be indirectly at fault by helping people to go faster in the first place, I suppose.
Sadly it is the reason that you need to think hard before putting resources into building a section of trail that is at all steep. The surface doesn't last long because of braking bumps.Posted 7 years ago
So I'm right to be a bit miffed then? I mean we were hooning down there in the days when 63mm travel was rad and discs hadn't even been born.
I like to climb back out of trails like that, and the top used to be hard, the balance of keeping the front down and rear under traction was key, now it's fubbered.
Edit, everyone knows I'm an old mincer, but I've never needed to brake on that before. It was always a drop in followed by a gentle rise that naturally scrubbed the speed off.Posted 7 years ago
I recall having a long (and thrilling!) discussion about this on BM years ago. The consensus was that it was probably hardtails that tended to start them (as the back wheel skipped/locked over slight undulations in the trail under hard braking) but then it was full susser that probably made them worse as they followed the trail so any lockup would dig the holes deeper and deeper.Posted 7 years ago
To expand on my post, i mean the deep ripples at about a foot apart
Pure conjecture, but hard braking tends to cause a single dip to form. Dragging brakes over the dip causes another dip to form as the suspension rebounds into and wheels relock as the bike thumops back into the ground, so a second dip forms. Repeat ad nauseum and wuith many many bikes dragging brakes, so get a whole series. Pretty soon, people start dragging brakes earlier and earlier becuase the corner is now 'bumpy'. So you get a whole long set into the corner.Posted 7 years ago
Because they spoil the flow of trails. You could just cover every trail with rocks otherwise and claim that you're making them more technical but most people would prefer better flow.
FWIW, I'd pretty happily ride smooth, flowing, rolling but very twisty trails all day long – that's where I really get my thrills.Posted 7 years agoglenpMember
Usually the problem isn't so much that the trail is no longer smooth to ride, more that it is no longer smooth to water. Once you have a sufficiently abrupt dip water will puddle and catch and then erosion starts in earnest. A durable, sustainable trail lets the water move slowly across and away from the trail.Posted 7 years agothisisnotaspoonMember
Dunno about a lak of flow, they by default only appear in sections that are steep and fast, where you would be braking into a corner.
So your mincing and the the bumps arent letting you brake as much as you other wise would.
The labarynth at Swinley is full of braking bumps, doesn;'t ruin the flow one bit even on a hardtail as 90% of them are into corners with no real need to brake (or if there is, the lost speed in the bumps is suficient)Posted 7 years ago
In my experience they often appear on flat trails too – just before a corner where you need to brake reasonably hard – eg somewhere that some people lock up.
They also definitely do affect flow since they're nicely front wheel sized more often than not and nice and deep once the rain/puddles have got to work making them increasingly deep.Posted 7 years ago
Deffo ruined the flow, I suppose it's fine if you have plenty of travel and weren't the sort of person that actually ever rode uphill.
It's the same old thing, people see trails like that as only worthy of rolling down. It's like another local steep drop that's a great technical climb. But then some muppet cut a drop off into it so that was end of trying to nail it going up.Posted 7 years ago
Plus both are natural trails not manmade.
I was cursing and ranting to myself about the state of a local fun bit of trail. The 'Roller Coaster' if you know Woburn. The main drop into it is covered in stutter bumps and I had assumed that it was due to riders hauling on the brakes. But what annoyed me is that it made the climb back up almost impossible, it was hard enough anyway. Then again there isn't many folk that like to ride up trails like that.Posted 7 years ago
Then I got to thinking is it more likely to be caused by people on full sussers? It's been rideable for decades and now in just a few months it's ruined.5labMember
they are (I think) caused by rear suspension and non-floating calipers. As your suspension compresses, the rear wheel moves slower, which does something (i think causes your braking time to be longer) and enlarges braking bumps. The very first ripple is always caused by something else (say a root) though. Hardtails tend to smooth them out, as the back wheel hops onto the upslope, knocking it a little flatter each time
btw, none of the bumps in the UK are anything like as bad as a well worn alpine trail. End up having to find a high or low line most of the time just to try and keep momentum (normally before the lightest of corners anyway). landing a large gap to braking bumps is interesting, to say the least.Posted 7 years ago
Yes the section of trail that is now covered in bumps is arrow straight, plus you can see ahead of you a very obvious rise/berm that would clearly slow you down. The stutters start just yards from the start of the drop in.Posted 7 years ago
In fact it used to have such a nice flow you could do it on a crosser. The rest of the trail is still perfect BTW.
They are caused by suspension. As people wheels hit a bump, their suspension comes up and then down again further down the trail hence the stutter bumps.
They also appear on dirt roads that are driven on by cars – for the same reason. They can go on for miles as car wheels are always being driven, so it doesn't necessarily have to be from braking.Posted 7 years agotamworthcrowdMember
they are (I think) caused by rear suspension and non-floating calipers.
why on earth would suspension be to blame for brake bumps? if you go through the first bump on a hardtail, the rear will be bounced into the air a bit, and on reimpact with the trail, rear wheel all locked up (because you're braking), it'll scratch some soil away creating the next bump. rinse and repeat. if anything, rear suspension should reduce this tendency by smoothing the impact of the rear wheel.Posted 7 years ago
the reason you get more bumps than you used to is because it's been a very very dry summer so far, more people ride, and thanks to better bikes and brakes, speeds for approaching corners are higher than they used to, so more and later braking takes place.cookeaaSubscriber
Have the trails seen a significant increase in traffic? I guess it is enevitible with more riders there will always be a proportion who mince about on the brakes, it tends to be a few riders coming in a bit heavy on the brakes causing that first ripple, which in turn forms a puddle, and the next time they approach their braking point shifts a foot back (now they are approaching a puddle/ripple before a corner) thus starting the creation of another ripple/bump….
I suppose you could argue that suspension has the knock on effect of allowing a poor rider to get to higher speeds than they would manage on a HT and then of course as they are braking too late/sharply from a higher speed they will displace more material and skid about causing more damage each time, so I guess bounce could be at least partly blamed, but in general an increase in traffic brings these trail wear problems out more…
Not knowing the details of the trail, is there any way you could make a feature out of the damaged section? A small kicker or exaggerate the ripples into a pump section to try and modify riders behaviour?Posted 7 years ago
Would a trail repair accompanied by improved drainage help the issue or would it just be a sticking plaster solution?
cookeaa I wouldn't touch it as it's a natural trail, adding something like a kicker would not only ruin the aesthetics even more, but make it almost impossible to ride back up.Posted 7 years ago
I think what annoys me is that a lot of riders adopt 'bike park' attitudes to natural trails to the point that I've even been told I'm going the wrong way WTF 😯
Perhaps it'll get better come winter I don't know, but yes for an area that's classic xc country there has been a huge influx of padded up visitors. And apart from the man made play area it's all rideable on a cyclocross bike.
tamworth, I was going to add the hardtail effect to my post but forgot 🙂
I think it's less though because under hard braking the rear wheel isn't on the floor much, and the front is pressed into the ground where the tyre will absorb the lumps etc.
I only ever remember one instance of braking bumps back in the fully rigid days. And they were minor and quite close together. The great big bumps on DH courses are on a different scale.Posted 7 years ago
Remember 24" wheels on DH bikes? One of the reasons they never worked was because they'd drop into braking bumps and get slammed about all over the shop, far more than the 26" wheels that (mostly) created them. It seems that different wheel sizes create/fit different sizes and shapes of braking bumps. Is there some kind of resonance/frequency effect going on?
If so, your solution is to buy a 29er.Posted 7 years ago
Nothing but then neither does questioning the appearance of bumps on mtb trails
Ahh. Maybe a slight misunderstanding. I'm not questioning the appearance of bumps, but having a tongue in cheek poke at those that want everything nice and smoooooth. 🙂
I like it bumpy, see? If I wanted smooth, I'd ride on the road. 😉Posted 7 years ago
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