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[Closed] Simplicity vs Performance - Suspension design

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[#10774533]

So being on the brink of purchasing a steel, single pivot, 29er frame (Starling Murmur), its the first time I will own a steel, single pivot, 29er.

I test rode one and fell in love (my mate also has one and is enjoying it).

I also like the fact the frame has two bearings and not much else going on, so its fairly maintenance free.

Out of interest, what drives you when choosing a new frame? Outright performance? Simplicity? A combination?

Discuss......


 
Posted : 20/08/2019 12:25 pm
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Smiles. That's the only important factor unless you race.

Of course, there might be a more smiley bike out there somewhere, but who's to know? Ride bike, like bike, buy bike. It's that simple.


 
Posted : 20/08/2019 12:32 pm
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Singletrack should do a group test of knackered, abused bikes that have seen no maintenance.

1 x hardtail
1 x single pivot
1 x multi bearing'd bike

maybe also 1 of each bike in mint condition.

and compare how the performance has degraded between the models and if the fancy suspension design means much if you don't maintain your bike. It might revel nothing or might reveal everything.


 
Posted : 20/08/2019 12:40 pm
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I find myself agreeing completely with molgrips, again - I'm in no shape to be thinking about winning anything, so it's all about "do I like this?"

And then not spending the next year wondering if something else would be in tangibly better!


 
Posted : 20/08/2019 12:45 pm
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I want the bearings to last so a good design well made is what I look for. Then when the bearings do need replacing I won't be so bothered whether there are two or eight. My preference so far has been Horst link type so plenty of bearings when the time comes


 
Posted : 20/08/2019 1:15 pm
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R_B +1ish

There's a difference between for example a multi pivot suspension frame that's not quite aligned properly and eats bearings, and one that could potentially last the lifetime of the frame. Most bikes with short links should fit into that category. So something like a Specialized stumpjumper needing 12+ bearings and a kit costing £100+ labor isn't really such an issue if it only needs doing every 3 years.

On the other hand some multi pivot frames are just easier to service so it's not a problem.

Singletrack should do a group test of knackered, abused bikes that have seen no maintenance.

1 x hardtail
1 x single pivot
1 x multi bearing’d bike

maybe also 1 of each bike in mint condition.

and compare how the performance has degraded between the models and if the fancy suspension design means much if you don’t maintain your bike. It might revel nothing or might reveal everything.

Probably depends on the rider, some people will just ride anything even if it sounds like a skeleton avoiding the swear filter in a biscuit tin, others will refuse to ride if the jockey wheels feel a bit gritty!


 
Posted : 20/08/2019 1:39 pm
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It's not quite as simple as that, particularly as multi-pivot designs put lower forces through each pivot under lateral and torsional loads, so (as long as nothing is misaligned) can give potentially far better bearing durability (obviously you can overcome this on a single pivot by speccing massive bearings, which you have space to accommodate more easily).

I'm therefore pretty much with Rubber Buccaneer. It's like frame materials - not worth worrying about as you can make a very durable or very fragile frame out of any commonly used material.


 
Posted : 20/08/2019 2:07 pm
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Out of interest, what drives you when choosing a new frame? Outright performance? Simplicity? A combination?

Discuss……

You missed budget/affordability from your list.
Sadly it is a factor for some of us, and we have to ride what we can afford, not what we'd really lust after...


 
Posted : 20/08/2019 2:09 pm
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lust is the number one factor in bike purchase imo.

Then its design. bikes are fairly simplistic. theres a lot of variations on a theme and i cant believe stuff that goes out with rubbing cables / shimmed bearings and all sorts of stuff like that. Bodges around a bad design imo.

then if its fun (for me) i know some folks have bought bikes on them being fast. I bought my last bike because it was fun and as it turned out a bit slower than others.

Maintenance is low low low on my list.

As others have said i would change my bearings every year, check every 6. I have friends that are running the same bearings after 5 years. Apparently they are fine. I know they are not!


 
Posted : 20/08/2019 2:52 pm
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a good point cookeaa.

Do we see a trend of more expensive bikes having multi linkage suspension?

Although you can still spend 6k on an orange...?!


 
Posted : 20/08/2019 2:54 pm
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It’s not quite as simple as that, particularly as multi-pivot designs put lower forces through each pivot under lateral and torsional loads, so (as long as nothing is misaligned) can give potentially far better bearing durability

I'm not so convinced, you could I suppose halve the load in the main pivot if the chainstay linkage took half the force, but on the whole those bearings tend to be much smaller. Single pivots with the pivot on the downtube tend to be much wider too so it's better triangulated than squeezed between the chainring and seatube.

Do we see a trend of more expensive bikes having multi linkage suspension?

Naa, bossnut is a Horst link and orange, starling, etc are all single pivots.

I don't even think it's simpler to make, look at the number of welds on an orange or starling (or going back in time, bullit or heckler). One piece, but far more complicated to fabricate.


 
Posted : 20/08/2019 3:22 pm
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I’m a serial bike component destroyer (heavy, frequent hard riding, all weather) and switch to a single pivot frame a couple of years back to reduce and simplify maintenance – from that perspective it’s certainly worked. I find multi-pivot only as good as their weakest joint, and if that goes the rest follow in short order as the load tends to transfer to the next weakest joint. Not that it would stop me owning a multi pivot again (the rest of the family bikes are, they just don’t see the same levels of abuse) but I’d definitely seek out single.

Choice of single pivot frames is limited though, most manufactures make multi pivot. While it might be true they slightly superior in performance, it’s probably more because manufactures make what sells first and foremost.

The frame I bought – the last of the 27.5 Santa Cruz Hecklers – was discontinued by Santa Cruz in favour of the alloy Bronson. More money, more profit, more demand I guess. Not sure what I’ll replace it with when it finally dies, nice to see manufactures (other than Orange) making single pivots.


 
Posted : 20/08/2019 3:34 pm
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TBF budget has always played a part for me and because I tend to buy 2nd hand frames I've had a mixture of both simple and complex FS bikes.

If you want robust and functional bushes rather than bearings are cheap and cheerful and work (I doubt most of use could really spot the difference).
If you want to spend your life maintaining a bike buy something with a Lawill linkage back end... the biggest factor (IMO) isn't the linkage (or lack thereof) but the shock, a crap shock can ruin an otherwise good bike and a good shock can improve an otherwise unremarkable one.

Single pivot/4 bar/faux bar? all much of a muchness now IMO.

People rave about the Bossnut (cheaper end of the Single pivot spectrum) and whatever fancy FSR or VPP concoction SBC or SC are pushing this week.

The Murmur is an interesting one as it's USPs are different from most of the rest of the market, a bouncer trading on the whole "Steel is real" thing plus the simplicity of a single pivot coupled with sorted geometry, rather than composites and "high tech" multi-pivot designs...
But it's still and £1800+ frame, if you've arrived at the conclusion that you need to spend that amount, on that particular frame, it's going to be because that fits you're specific needs better than the equivalent Al/carbon hyper machine that the bigger outfits would tend to flog you...
Of course if it was just about "simplicity" of the suspension design you'd just buy a Bossnut and throw the remaining budget at accessories and toys...


 
Posted : 20/08/2019 4:42 pm
 DezB
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Budget, looks, ride..

My bike only has 2 bearings... however it has loads of bushings.. I serviced it recently and really should've taken a pic of all the parts laid out on the garage floor. Was quite scary (especially as I am very prone to losing small parts in my garage!).
However, having serviced that, and a few Yeti 575s in my time, complexity doesn't come into my decision.


 
Posted : 20/08/2019 5:07 pm
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Echo previous comments ...

I don't race so most important factor for me is "is the bike fun and does it make me smile when I ride it"

I check to see if the manufacturer has an OK reputation regarding durability and quality but after that I just go for what feels good regardless of 1 bearing or 100 bearings!

Also its possible to badly engineer a simple design so it is not durable and possible to engineer well a complicated design so it is durable. So complexity of the design is not a big factor for me but the reputation of the design is.


 
Posted : 20/08/2019 7:00 pm
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I bought my last frame because it looked nice and it was the style of bike that suits my riding (somewhere between XC and Enduro).


 
Posted : 20/08/2019 7:03 pm
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I've got a Starling Swoop, and over the years have ridden lots of different designs, materials, suspension systems. Initially I wanted the Swoop to get the geometry I wanted (I'm very long in the body and short in the leg, and wanted to be able to run a 150+ dropper post).

I would say the performance of any suspension bike (in fact any bike) is hugely affected by set up. I've ridden complex designs that have felt terrible, but with a bit of tinkering have become excellent.

I love the bike and would happily get another, or a murmur. The suspension system might be simple, but don't confuse simplicity for "worse".

If you have test ridden the bike and like it, then I'd highly recommend one.


 
Posted : 20/08/2019 7:26 pm
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I think reading magazines and reviews over the years helps hammer home this message that linkages / multi pivot / VPP / and all sorts of modified axle path is better.

For elite riders riding hard on DH bikes with 20mm travel, this is maybe true. For average joes on 140mm travel trail bikes, maybe not so much...

My previous susser was a Pole Evolink, which drove me nuts with it's incessant creak form the poorly designed and executed BB link. Cue much changing of expensive bearings and truly shite customer care. Never again!

I always remembered riding an Orange 5 Alpine at a demo years ago, on the Laggan black. It stuck with me as the best susser I had ridden. I didn't buy one when the time came though, because of the aforementioned conditioning that SP is bad.
Once I got rid of the Pole, I got me a custom Murmur running a Fox X2 shock. It's fantastic. The bearings, once they die, are £4 each and a ten minute job.


 
Posted : 20/08/2019 8:41 pm
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Complicated linkage suspension is great for marketing. If they were so much better than single pivot designs the. Bikes with single pivot designs would continually and consistently get crap reviews. They don’t. I suspect it doesn’t matter that much and really down to how the bike feels. But humans are adaptable so even if you get a bike that doesn’t suit you at first you can adapt and make it work. How do you think pro’s get on when they change sponsors and get new bikes. If they’re successful and the bike is so much of a big part of their success then there is no way they’d risk not winning and changing bikes. You’re just as well buying from colour preference or brand preference than trying to be clever about analysing the suspension set up.


 
Posted : 20/08/2019 9:06 pm
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I think reading magazines and reviews over the years helps hammer home this message that linkages / multi pivot / VPP / and all sorts of modified axle path is better.

For elite riders riding hard on DH bikes with 20mm travel, this is maybe true. For average joes on 140mm travel trail bikes, maybe not so much…

You say that But Amaury Pierron is winning the odd WC DH race on a Commencal with a high, single pivot (with linkage driven shock), Danny Hart is still inside the top 5 at present on another linkage actuated single pivot. So Elite WC DH would seem to suggest that Horst/VPP/DW/single pivot?... Meh, they all work well enough. I'd worry more about tyre choice...


 
Posted : 20/08/2019 9:12 pm
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It's all about smiles. I was put off single pivot after my orange 5 a few years ago that would lock the rear suspension when you used the back brake. They may have moved on since then and fixed the issue


 
Posted : 20/08/2019 9:21 pm
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I was thinking similar thoughts myself recently while writing a review of my Orange.

People - usually internet dullards - are quick to point out the downsides of a single pivot (though there's only one real issue IMO), but there's much less talk about the big upside of how a good one rides.

My Stage 6 is without a doubt the most engaging, fun and versatile MTB I've owned. And it's very fast too, FWIW.


 
Posted : 20/08/2019 9:22 pm
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I'm of the opinion that there's very few people around, me included, that could tell the difference in a blind pepsi-style test between each different suspension platform. I've not had that many full sussers - Heckler, SB66, Capra, Spectral 29 and now Bronson.

The only one I really had to work at was the Capra, to try and get the suspension working as a pedal all day bike took a bit of tuning, but got there eventually. The Heckler just worked, Yeti was hands down the best descending bike I've had, but 120 quid in bearings on a regular basis pissed me off a bit. The canyon was decent, if unspectacular, and the Bronson just does everything well.

I'll be keeping it for at least 5 years, it's only 2 years old now and still feels packet fresh, and the free bearings are a really good added bonus. Yes, it was expensive, but some folks spend a shit load on bikes in 5 years, and this is the only MTB I have.


 
Posted : 21/08/2019 9:57 am
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I’m of the opinion that there’s very few people around, me included, that could tell the difference in a blind pepsi-style test between each different suspension platform.

+1


 
Posted : 21/08/2019 10:41 am
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I have found that without a decent shock pure single pivots without a secondary link bottom out far too easily and blow through their travel too quickly.


 
Posted : 21/08/2019 1:35 pm
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I also like the fact the frame has two bearings and not much else going on, so its fairly maintenance free.

No bearings / bushings on the shock mounts?

What do I look for? Erm, one I like and can afford


 
Posted : 21/08/2019 1:45 pm
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Single pivot is distinctive enough to identify in a hypothetical blind test, I reckon.

Everything else would be harder to differentiate, I agree


 
Posted : 21/08/2019 1:50 pm
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A mix of Performance/fitness for purpose and lust from me.

I was kind of anti single pivot for a long time, using pretty much anything but SP (had VPP, FSR and DW).

Then I tried a high single pivot with an idler (linkage driven shock). By far the best descending setup I’ve ever used. Not quite as good as a DW link for climbing smooth trails but as soon as it gets techy, HSP wins.

The DW link bike will be replaced with a HSP trail bike.


 
Posted : 21/08/2019 2:47 pm
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I doubt you could say 'this is a horst' or 'dw' or 'vpp' in a blind test, but you could probably pick a bike you liked. Even trying two different bikes with the same travel and suspension design, small changes in their implementation have a big effect on how they ride.

Single pivots (simple ones anyway) do generally tend to ride in a certain way though which is a bit marmite.


 
Posted : 21/08/2019 4:43 pm
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I have found that without a decent shock pure single pivots without a secondary link bottom out far too easily and blow through their travel too quickly.

But that's tunable via the shock, or should be.


 
Posted : 21/08/2019 4:52 pm
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Never liked single pivots myself. The way they pedal, respond, brake, flex. Everything. There's no way I'd have one.

Choosing bikes is pretty easy though. Just ride them. A mate has a DW-link bike, which is really well prepped/specced/setup but prefer my four-bar pretty much straight away. Whether it's the geo or what, who knows, but it's clear in no time.


 
Posted : 21/08/2019 4:53 pm
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For me weight and efficiency, e.g. the bike has to surge uphill with each pedal stroke, can't stand anything with a sluggish response. I'd happily sacrifice downhill speed for uphill efficiency.


 
Posted : 21/08/2019 5:05 pm
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Simplicity/few moving parts isn't as big a deal as people think... I pay £32 for a complete bearing set for my frame (Remedy) but most times I don't even need to do that, I just change the bearings that need it. And it's like 1 hour's work or so. An absolute drop in the bucket considering the price of frames etc.

Not to say simple/lower maintenance frames can't also perform well, but I think it's basically mental to give up even a tiny bit of performance to reduce the number of bearings.


 
Posted : 21/08/2019 6:24 pm
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But as per my previous comment, what if you gain a really fun ride character by having fewer bearings?

Is "performance" just making the trail feel as smooth as possible?

What if a bike was more challenging to ride but also one of the faster contenders in its class?


 
Posted : 21/08/2019 9:04 pm
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Further to this thread, I did a review of the Stage 6 which may be of interest to some...
http://unduro.co.uk/mtb/review-orange-stage-6/


 
Posted : 02/09/2019 10:14 pm
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“Single pivot is distinctive enough to identify in a hypothetical blind test, I reckon.”

I’m not convinced.

There are two big differentiators for suspension performance on MTBs, anti-squat (and thus pedal kickback) and leverage curve.

The former depends upon the pivot point or instant centre relative to the chain line. The latter depends upon how the swing arm moves the shock.

The latter can’t be manipulated on a single pivot significantly without an additional linkage but plenty of complex designs have similar curves to single pivot bikes. The former depends on where you put the main pivot or where the links point to - that point can be the same for single pivots or complex designs.

Give a bike loads of anti-squat and it’ll pedal well but kickback somewhat. Doesn’t matter what the suspension design is, that’s what you’ll notice.


 
Posted : 02/09/2019 10:35 pm
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How bad is kickback? My long travel bike has loads of pedal kickback, I notice it but it doesn't really stop me riding stuff. I mean, the bike is slow on the ups but that's cos it's got massive slow tyres on it, and the riding position is upright.


 
Posted : 02/09/2019 10:44 pm
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You'd tell a single pivot from the stiffening under braking, assuming you were familiar with the feel from riding one previously of course.

And having the opportunity to ride it somewhere at least mildly bumpy.


 
Posted : 02/09/2019 10:49 pm
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“You’d tell a single pivot from the stiffening under braking, assuming you were familiar with the feel from riding one previously of course.”

How much a bike stiffens under braking (aka anti-rise) is purely a function of the pivot point vs the rear tyre contact patch, you just draw a line through the two and the the steeper the angle vs the horizontal, the greater the anti-rise.

It’s very high on high pivot bikes like the Commencal Supreme, and it’s very low on FSR style 4-bar bikes where the chainstay and upper link co-rotate and point a long way forwards, or on Split Pivot / Trek bikes.

But anti-rise is very similar on 4-bar bikes that counter-rotate (where the upper link hangs from the top tube), Switch Infinity, VPP, KS-link, linkage driven single pivots (Cotic, Kona, etc), and simple single pivots - you can’t separate the designs, they overlap far too much in braking behaviour.

Amazing how powerful placebo effect is, every bike journalist is convinced that single pivot bikes are totally different under braking to all others.


 
Posted : 02/09/2019 11:35 pm
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all very interesting stuff.

Is there a guide anywhere of the advantages or disadvantages of the various suspension setups?

I am still pondering the purchase of a Murmur, but I tend to ride most of my downhills with a bit of back brake drag, so fear 'brake jack' 'anti rise' etc. Or as mentioned above, is it placebo effect or something literally to just not worry about and to just get on and ride?! (I have a problem with over analysing things!)


 
Posted : 03/09/2019 9:33 am
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Is there a guide anywhere of the advantages or disadvantages of the various suspension setups?

There probably is, but it's all rubbish. I mean theoretically one design might transfer slightly less bump impact to the rider, but there are SO many more variables that affect how much you enjoy a bike that this is not significant.

Basically, demo a bike, if you like it buy it. You aren't trying to eke out maximum performance (unless you're a racer), so just ride whatever's fun.

Brake jack especially is bobbins. I mean, on some suspension designs if they have the brake caliper on a different linkage to the wheel, then operating the brake can make the rear suspension extend. This is rare and I'm not sure if anyone designs frames like this any more - what people notice when the rear suspension extends under braking is the simple fact that their weight has pitched forward which is always going to make the front go down and the back go up. Some designs may minimise this which makes other designs feel worse. My long travel bike dived terribly, but that's cos I was riding it with the saddle all the way up. Dropping the saddle meant I could get behind the bike properly, problem solved.


 
Posted : 03/09/2019 9:43 am
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@molgrips - Some current Horst type designs appear to have the rocker link arranged so that the braking/suspension interaction is pretty much zero in the initial part of the suspension movement. That is, the link between the "seatstay" and the rocker pivot is near horizontal. Look at current Transitions and Treks, for example. Whether braking behaviour was part of that design decision I don't know, I would imagine that fine-tuning the pedalling/suspension behavior and the spring rate wouild be higher priorities*. As you say, the major factor you will notice is the front diving, which isn't really anything to do with that.

I wouldn't rule out that some people might notice the effect when they initially squeeze the rear brake. I could do a back-to-back test as my previous frame is still in the garage, but just moving from one to the other I didn't notice anything different in the braking department (same brakes, wheels etc.).

*From an engineering perspective that is. Trek make a big play of the braking thing in their marketing, but engineering bollocks and marketing go hand in hand as we know. I read somewhere that the reason they went for their concentric suspension and axle pivots was to get round an Ellsworth patent, what they actually wanted to do was a Horst with the axle and pivot point close together - which is what many current Horst type designs have, making them behave like single pivots (apart from the braking thing...)


 
Posted : 03/09/2019 10:57 am
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Some current Horst type designs appear to have the rocker link arranged so that the braking/suspension interaction is pretty much zero in the initial part of the suspension movement.

Yes, Horst links are potentially a problem here. But on other designs such as single pivot or linkage actuated single pivot where the calliper is fixed to the same piece of metal as the wheel, there's no direct interaction between brake and suspension.

EDIT Just had a look at a Transition Sentinel online. Nice looking bike isn't it?


 
Posted : 03/09/2019 11:01 am
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“But on other designs such as single pivot or linkage actuated single pivot where the calliper is fixed to the same piece of metal as the wheel, there’s no direct interaction between brake and suspension”

Yes there is. The rearward force from the ground to the rear tyre contact patch generates a torque that attempts to lift the rear suspension, thus squatting the back end of the bike downwards.


 
Posted : 03/09/2019 11:27 am
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@molgrips - my previous bike (what I still have the frame of) is a Transition Bandit, with the caliper attached to the swingarm. I was looking for a longer travel modern geometry bike and nearly got an ali Sentinel, but a carbon Trek Slash frame came up on PinkBike so I took a punt on it. Haven't regretted it, the Slash is awesome, but I am sure the Sentinel would be also.

@chief - I am not sure about that. The torque from the rear braking forces is transmitted through the axle and caliper, ie to the bit of metal/carbon that connects the two. Things can be arranged for that torque to compress or extend the suspension, or to do nothing. In addition to that of course, there is the fact that under braking weight will shift to the front. With rear suspension arranged for there to be no brake/suspension interaction, the rear suspension would extend, as it would if you were doing all your braking on the front. With a caliper on the swingarm arrangement, the braking forces would oppose this. Which may or may not be an appreciable effect, or a good thing.

ETA if the (virtual) swingarm is not horizontal, there will also be an effect from the net rearward forces on the axle, but I think this will be even smaller particularly on 29ers.


 
Posted : 03/09/2019 11:55 am
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