There is lots of talk about 1x, but I rarely see any mention of the effect on suspension kinematics.

I tried a 1×10 setup on my Solaris HT 29er, but didn’t really get on with it. I thought it might work on my 26″ Five though and might still give it a go, but looking at the anti-squat and pedal feedback numbers I’m wondering whether to bother.

I typically climb (seated) in my granny gear, which gives nice high anti-squat numbers. So, when I push on the pedals the suspension tries to stiffen, pushing the wheel into the ground and increasing traction. With a typical 1x setup it looks as though the anti-squat would be much lower. Well below 100% in fact. So pushing on the pedals would compress the suspension, lifting the rear wheel, reducing traction and making it bob more. Doesn’t sound good.

It’s not just climbing though. When I get to the top I shift into the outer ring (usually leaving it in a fairly large rear sprocket). So chain tension is nice and high and pedal feedback is at its lowest. With a 1x setup I’d be shifting into smaller sprockets, reducing chain tension and increasing pedal feedback. Again, doesn’t sound good.

It’s almost as though Orange designed the bike to be used with multiple chainrings 🙂 But, if that’s the case, why do their flagship RS models come with 1×11 ? What am I missing?

Also, I thought this might just be a Orange thing, but it would appear that the same general trend is true for most designs. Anti-squat is higher with smaller chainrings (and smaller sprockets) and pedal feedback is inversely proportional to anti-squat. So, why do so many manufacturers supply 1×11 setups on their flagship models.

Maybe suspension kinematics just isn’t that important. But in that case, we’d all be riding round on single pivots 🙂

*JCL to the forum please, JCL to the forum*

What am I missing?

The ability to let things that don’t really matter slide.

What am I missing?

Just getting on and riding it?

I’ve used triple, double and single of various sizes on single pivots, cant say i can tell any difference. I could tell a difference after a proper shock tune.

I don’t hold much truck with ‘chain tension pushing the rear wheel into the ground and giving more traction’. If you were a fixed I moveable object that would be the case, but all that really happens is the bike stands up more in its travel, because the Easrth is the fixed immovable object. It stiffens your suspension and reduces its compliance to bumps when climbing. This is the origin of ‘single pivots feel like hard tails under power’. Using chain tension in this way can be a boon on smooth climbs and a detriment on rough and technical climbs, but as ever, it’s more about the rider.

stop over thinking / worrying about stuff. Just ride your f***ing bike

edit: 🙂

I’d say you’re definitely missing the “Big picture”…..

It’s like people who say clutch mechs affect the suspension on their bike. Technically, yes, the extra load does affect the suspension, but the fact that the affect is practically too small to measure, let alone feel seems to pass them by……..

It’s not just climbing though. When I get to the top I shift into the outer ring (usually leaving it in a fairly large rear sprocket). So chain tension is nice and LOW and pedal feedback is at its lowest. With a 1x setup I’d be shifting into smaller sprockets, INCREASING chain tension and increasing pedal feedback. Again, doesn’t sound good.

Larger chainrings and sprockets decrease chain tension, and for a given increase in crank to axle distance will result in a smaller rotation of the cranks to absorb the difference which I am assuming will reduce the pedal feedback.

But I bet there isnt (or shouldnt be) a suspension design out there that does not work pretty well on the middle ring – which is all a 1x is.

N

Sorry for the delay in responding, I’ve been out riding my bike 🙂

I knew when I posted this I’d get the usual “stop thinking” responses. I mean everyone knows that the biggest problem these days is all these people thinking for themselves. What we need is more blind faith and ignorance. That never goes wrong.

Why anybody who doesn’t want to think about the details of how their bike works would open a thread on the subject, just to tell other people not to think about it is beyond me. But I’m all relaxed after my ride, so I’ll just focus on the few helpful responses, if that’s OK.

I don’t hold much truck with ‘chain tension pushing the rear wheel into the ground and giving more traction’.

I think I see what you are saying, but even though I’m not as massive as the earth my mass is not insignificant. If pushing on the pedals is stiffening the suspension then it is trying to increase the distance between me and the ground. Surely that means that it will exert a force up on me and one down on the ground. Whether the later is significant will presumably depend on the size of the force and on my mass. I certainly find that my Five scrambles up loose climbs better than my 29er HT, despite the supposed increase in traction with the larger wheels.

Larger chainrings and sprockets decrease chain tension

Is that right. They pull the chain tighter (so the force from the rear mech is greater as the spring is stretched further) and seem to reduce chain slap, which is what I was getting at. But maybe the tension within the chain itself is lower.

I’ve used triple, double and single of various sizes on single pivots, cant say i can tell any difference. I could tell a difference after a proper shock tune.

Fair point. I’m happy to concede that these anti-squat and pedal-kickback numbers don’t actually matter that much out on the trail. But the whole justification for having loads of pivots on your bike (when one would do) is based on equally small changes in these numbers.

This thread is useless without JCL graphs.

“Do the Math” as they say. Plot out where your pivot centres are, then plot out the chain loads and see how they affect the average spring rate. What you’ll find is, that unless you have some ridiculous pivot centre (which you just don’t get these days on modern frame designs) the effect of the chain loads is really rather small compared to the possibly 100kg sack of spuds sat on the bike……..

I think this is an interesting question and in theory, exactly what a mountain bike forum is for. I remember reading about dw linkages and how they worked due to climbing in granny, feuding in middle and decendibg in big ring. It felt like the next day, 2x was the must have set up. This question is only an extension of that.

Don’t know what the answer is and those that understand such things can be baffling. I remember trying to get my head around an interesting argument that travel adjustable forks Mar climbing harder in the lower setting.

Having spent far too much time looking at graphs of suspension analyses I think there’s a clear pattern of pros and cons to different drivetrains on different bikes. A bike with ~100% anti-squat in the middle ring will have too much in the granny – that’s just as bad as too little because it makes the bike rise (at peak torque) and fall (minimum torque) under pedalling instead of falling and rising (likewise).

This is just anecdotal evidence but it seems that those I ride with who are on bikes with well optimised anti-squat for their gearing don’t have to use extra damping (eg pro-pedal) to stop the bob whilst those who aren’t do.

I’ve got a dw-link bike and run 1x

I also have a granny that I can kick the chain into if it all gets a bit much for me

At least now I’ll have something to think about when I’m twiddling up Mam Tor on saturday

By the way, the taller you are, the more anti-squat you need, and vice versa.

If I still had a granny I would’nt kick the chain onto her…..even if it did get too much for me.
She used to give me Wurthers Originals

When I used to use a granny ring I used lockout or climb mode. Still do.

You just adapt your riding style. I’m noticeably quicker on the up 1x because it’s most efficient to get the cadence up and hold it as opposed to slowly grinding up when you can’t spin lower speeds. Definitely less Bobby as well. When I get tired and resort to mashing the pedals down in too high a gear it feels like pedalling through mud.

Same on the top, just using spinning technique to ride smoothly helps – this I really can’t do though. I couldn’t see myself going back to using a front mech after years without, but if I did it would be for the outer ring not the granny!

Having spent far too much time looking at graphs of suspension analyses I think there’s a clear pattern of pros and cons to different drivetrains on different bikes. A bike with ~100% anti-squat in the middle ring will have too much in the granny – that’s just as bad as too little because it makes the bike rise (at peak torque) and fall (minimum torque) under pedalling instead of falling and rising (likewise).

This is just anecdotal evidence but it seems that those I ride with who are on bikes with well optimised anti-squat for their gearing don’t have to use extra damping (eg pro-pedal) to stop the bob whilst those who aren’t do.

I agree. We sell 75% 1x, and our Aeris is optimised for it. We have 1 2x bike in the demo fleet, and consistently that gets the worst feedback of all the bikes (by worst I mean least great – its not terrible but its not 95% gushing like the others), that optimisation really does effect the ride of the bike in a meaningful way. In a 32T set up I would say that our frame pedals as well as anything out there, and its got a nice balance of anti-squat and anti-rise to keep things stable for the stop and go stuff. Move outside of that set up by more than a few teeth and you can really feel the difference, So much so Im actually looking at a custom front double set up for those that really want it which will keep the gearing within the ‘peak’ range more of the time. Gear purists will hate it because it overlaps more ratios, but I think its worth it.

I don’t know about anyone else but my style of riding has changed a lot since moving to 1×10, which I’m sure makes far more difference than any minute details in the anti squat characteristics. I need to stand and hammer more often, so I end up riding more aggressively and faster.

I’m sure you’re correct about the effect, but I think you must be over estimating its magnitude significantly.

So it’s OK to talk about weight in micro fractions ie a wheelset that is 3% lighter or a 50g lighter seatpost that makes the bike 0.2% lighter but it’s not OK to talk about percentages of suspension movement/grip etc.

Seems to me the OPs post is considered, well crafted and intelligent which is more than can be said for some of the answers.

Thanks for the supportive posts folks 🙂

It seems that 99% of the replies are saying that it doesn’t matter but the one from a manufacturer (benpinnick) seems to be saying the opposite, if I understood correctly i.e. that it matters a lot and that if you move more than a couple of teeth away from the optimum chainring it will be noticeably worse. Of course, that’s an argument for 1x setups not against them, but it would suggest that these numbers do matter.

I take the point that anti-squat numbers above 100% are just as bad as those below 100% in terms of pedal induced bob, although I still think that you get an improvement in traction with the high numbers.

I also accept that the numbers depend on rider weight and height. We haven’t talked about what the numbers mean or how they are calculated, but maybe that is a step too far.

The idea of a “custom front double set up” is interesting and is something I’ve contemplated with my Five. If we accept that the bike was designed around a 32T chainring then it makes sense to stay in that as long as possible. Fitting a wide range rear cassette (e.g. 11-42) would allow me to stay in the 32T for pretty much all my rides. However, I know that I want a lower gear than 32×42 sometimes. Not often, but when I want it I really want it. So, I could fit something like a 28T “granny”, which gives me the same as my current 24×36 bottom gear. As you say, gear purists wont like it, but I can see the logic. If nothing else you could run it for a while and see whether you could get by without using the granny.

You’d think that any bike that this is important for, would be designed around the middle ring anyway- it wouldn’t make any sense to build a bike that only works well in the big or little.S o putting more gears onto the “middle” ring could be beneficial (if maybe not in a way that you’ll even notice) but probably shouldn’t be disadvantageous…

Northwind – Member
You’d think that any bike that this is important for, would be designed around the middle ring anyway- it wouldn’t make any sense to build a bike that only works well in the big or little.S o putting more gears onto the “middle” ring could be beneficial (if maybe not in a way that you’ll even notice) but probably shouldn’t be disadvantageous..

Yep – Santa Cruz and others always talked about optimising for the middle ring (although possibly in the context of “it’s shit in the granny”)

For years it seemed that fans of the single pivot (or maybe just fans of Orange) claimed that one of the advantages was the way that the suspension kinematics changed with the different chainrings. So, you had nice and neutral/active suspension in your 32T ring for descending and general trail riding, then a nice stiff feel with lots of traction in the granny ring.

But as soon as we got cassettes with a big enough range it seems that everyone (including Orange on their flagship models) wanted to dump the granny.

Mtbr has some threads on this although most are aimed at the dw link and dw himself has joined in.

In short, he says all designs benefit from variable chainline angles and that dw will be less effected by single ring set up than other designs (but then he would) but ultimately, we’re not talking about it not working single ring but more a case of it not being optimised.

However, your suspension works better with a triple, whatever the design.

Glad I’m still running 3×9 in that case.

I went 1×11 on my Rocket about this time last year from 2×9.

Yes I did notice a difference in traction on loose rubbly climbs, but I’ve largely countered that by just attacking a bit more and carrying more momentum.

Theoretically any decrease in traction on loose stuff (when you want the wheel to “dig in”) should be offset by less hooking up when trying to pedal up big steps when you want the wheel free to move with as little chain interference as possible.

I’m guessing the torque the rider applies to the chain and change in body positioning, muscle use, e.t.c. from cranking a slightly bigger gear (in most cases even though there will be some overlap) also affects things.

Is the “optimised for different rings” thing all about ratios? So with a 1×11 you get nearly the same gear range a multi ring setup. So when you are climbing the suspension may behave just like a granny ring combined with a smaller cassette?

I’ve got 2 dw-link bikes. One with a triple and a 11-36 and the other with a single and 10-42. Both climb very well. In fact the 1×11 bike (combined with a CC DB inline shock) feels like a mountain goat and that I can climb anything (tired legs depending).

My comment about chain tension was referring to tension caused by pedaling which will be hugely greater than any derailleur spring tension.

My understanding of the optimized for different rings is:
Bike 1 uses Granny and halfway through cassette for 22:22 ratio
Bike 2 uses Middle and largest cassette for 34:34
Both are using a 1:1 gearing but the tension in the chain is different and where it is acting relative to a pivot is different.
If the line of the chain in 34:34 makes an imaginary line that passes through the centerp of the pivot, it will react differently to the 22:22 where that line would act a couple of inches lower down.

Is the “optimised for different rings” thing all about ratios? So with a 1×11 you get nearly the same gear range a multi ring setup

No, that’s the ting; you can have two gears that are the same in terms of distance travelled per crank rotation, but they can have quite different suspension kinematics. Whether that difference is significant or not I don’t know. As far as I can tell manufacturers seem to think it is but (judging from this thread) most riders don’t.

It’s interesting to hear that Mr DW link seems to think that we should all use multiple chainrings to get the best out of our suspension.

EDIT: Beaten to it by Doh1Nut. Basically, what he said 🙂

DW’s triple vs singles post
Second entry down on, Oct 4th 2008.

As far as I can tell riders seem to think it is but (judging from this thread) most manufacturers don’t.

Fascinating link, thanks. That put the argument a lot more clearly than my original post. Mind you, it’s always easier to be clear when you actually know what you are talking about 🙂

Was trying to avoid work so did a pointless calculation on chain tension

Climbing at 500watts @ 100 cadence & 32teeth chainring

In one second 500w*1s=500J work done
In one second 100/60 = 1.66 crank revs * 32teeth * 1/2inch pitch = 677mm of chain.
500J/0.667 = 73 kg force

In one second 100/60 = 1.66 crank revs * 22teeth * 1/2inch pitch = 465mm of chain.
500J/0.465 = 110 kg force

Drop cadence to 30 to struggle up a technical climb
In one second 30/60 = 0.5 crank revs * 32teeth * 1/2inch pitch = 203mm of chain.
500J/0.203 = 250 kg force

Now, if you look at the line along which that force is acting (which is different for the 32 and 22 chainrings) and where that line is in relation to the pivot, you can see that those two options will have a very different effect on the suspension.

But you’d be spinning at 32/22*100rpm to do the same power output in the smaller gear = 145rpm
This gives the same chain tension but at lower torque at the cranks.

Fascinating link, thanks. That put the argument a lot more clearly than my original post. Mind you, it’s always easier to be clear when you actually know what you are talking about

It’s an interesting read and the MBR link in it is also good.

7 or 8 years later, I wonder how this statement sits with DW, SRAM and most FS brands –
“Variable front chainlines are ALWAYS going to be a good thing for mountain bikers who ride their bikes on variable terrains. Without them, suspension bikes might still be considered a bad idea, and I would most likely be riding motocross.”

I guess the take on it all now is that bikes are less all-round XC than they were in 2008 and we accept minor gearing compromise to get more ability or usage-bias elsewhere. The chain angle range of a wide-ratio 11s block is also wider than the 11-34s we had in 2008 though from what I remember of playing with FS Kinematics etc that doesn’t make as much difference as the front ring size/position.

So much so Im actually looking at a custom front double set up for those that really want it

Orange Bikes used to sell a 32/22 double.

Interesting thread, have been reading up on this lately, some good info here re:-suspension kinematics

http://www.i-tracksuspension.com/suspensiontheory.html