Single pivot with a coil - How does it function?

[beeb]

So I keep seeing pictures of single pivot bikes (or single pivot with yoke) and coil shocks and wondering how riders "get away with it"?

ie: a Pipedream Full Moxie:

Don't single pivot bikes generally have F-all progression in the suspension? What's providing the ramp up here? Is it just something lighter riders can get away with on mellower terrain?

I'm roughly about 95kg kitted up, and all I could see happening are:

A) Running a spring so firm the thing is basically a hardtail with a safety blow-off, or;
B) Riding with a reasonable amount of sag and just pummelling the bump stop in the shock through rocks and over drops.

Am I missing something? I love the looks of these type of bikes, would love to never use a shock pump again and love that coil traction feel, but I just don't get it.

This is the leverage ratio graph for the Full Moxie:

 

[wkkie]

I think that's all technical talk and the reality is that it just doesn't always pan out that way. It depends on the shock as well no doubt...

I've run a coil on a Dartmoor Blackbird (basically the identical rear end setup as that Moxie you pictured) and didn't have any of that stuff happen and I've got at least 10kg on you.

All that I found was that the difference from the air to the coil was that awesome smooth coil feel... But that's just my perspective. You could probably have jumped on and noticed something totally different.

Just go for it @beeb! Don't over think it!

 

[Daniel Hale]

shite that frame looks good , -pedal colour is all wrong though

 

[Isaakk]

Have a coil on the single pivot Marino at the moment, 400-488lbs progressive VALT spring on a CC DB-IL, 78kg rider weight, running around 28% sag. It seems to work okay! Had to wind HSC up a little & i'm still playing around with setup, but initial impressions are very good & haven't slammed the bumpstop at all like I feared might happen (or at least I haven't noticed it).

Coil feel is definitely a thing, rides so much smoother and yet seems to have better support at the same time. Back wheel feels like it's glued to the ground, even compared to a DVO Topaz (which are known for their small bump sensitivity and low breakaway force.

Also hot damn that Moxie looks sweet.

 

[Ultra Lord]

So I keep seeing pictures of single pivot bikes (or single pivot with yoke) and coil shocks and wondering how riders "get away with it"?

ie: a Pipedream Full Moxie:

Don't single pivot bikes generally have F-all progression in the suspension? What's providing the ramp up here? Is it just something lighter riders can get away with on mellower terrain?

I'm roughly about 95kg kitted up, and all I could see happening are:

A) Running a spring so firm the thing is basically a hardtail with a safety blow-off, or;
B) Riding with a reasonable amount of sag and just pummelling the bump stop in the shock through rocks and over drops.

Am I missing something? I love the looks of these type of bikes, would love to never use a shock pump again and love that coil traction feel, but I just don't get it.

This is the leverage ratio graph for the Full Moxie:

Yes.

 

[beeb]

I think that's all technical talk and the reality is that it just doesn't always pan out that way. It depends on the shock as well no doubt...

I've run a coil on a Dartmoor Blackbird (basically the identical rear end setup as that Moxie you pictured) and didn't have any of that stuff happen and I've got at least 10kg on you.

All that I found was that the difference from the air to the coil was that awesome smooth coil feel... But that's just my perspective. You could probably have jumped on and noticed something totally different.

Just go for it @beeb! Don't over think it!

It's interesting you mention that. I suspect you ride way more forward on the bike than me (ie: a lot better than me, lol), and that asks a lot less of the coil rear. I got on your Katipo on the fireroad the other day and instantly thought "Wow, this'd need to go up a spring-rate for me". I could've learned to live with it as it was, and suspect it'd monster rock gardens - but it felt odd not having much progression to push against.

I think my fear comes from having the Ripmos previously, I just didn't gel with the back end of them and bottomed them out pretty hard on some relatively mild stuff (ie, the second, steeper, not into a LH hairpin rockgarden on Junction track). They also had only a mildly progressive linkage. I tried volumn bands, and they still didn't feel right. What I've been wondering more recently is if I probably just didn't like the weight distribution (too long front, possibly slightly short rear) of them for my preferred fit, and maybe on something with more of a forward weight bias I'd have a bit more confidence getting into the aggressive position needed and not weighting the bike so much at the back.

While Waltly 3 is obviously going to be a hardtail - it really is a long-chainstay/weight-distribution experiment that if it plays out how I hope may lead to something like the Pipedream in the long term. I've already spent far too much on parts for Waltly 3 though, had to replace my side fence, and had a significant (but not unexpected) drop in income from the new job role I started late last year (and now also can't ride for 6 weeks thanks to the appendicitis either...). So it'll give me a good amount of time to mull it over, get Waltly 3 built and give it a good thrashing, get a feel for the geo, and do some saving for me now full 29er compatible parts.

But I just need to hear some thoughts that aren't based on my own preconceptions (and try listening to them for once! ) regarding whether or not it will actually work.

I think like @Isaakk says, with a progressive coil it could work.

And yep, they're a damn cool looking bike. Sigh, I miss having more money, haha.

 

[pink poodle]

Ive had a single pivot with coil (eastern slash 7+) and really liked it. The bike too some big hits under my weighty arse. I didn't like the way it rode over small square bumps.

 

[beeb]

Ive had a single pivot with coil (eastern slash 7+) and really liked it. The bike too some big hits under my weighty arse. I didn't like the way it rode over small square bumps.

So possibly over-sprung then?

 

[pink poodle]

So possibly over-sprung then?

Nah, in theory perfect spring for me at the time. Shock was a fox dhx3 I think. It just chattered a lot over roots and rocks etc. I smashed it down dozer's old coramba without issue. It also rode stairs nicely.

 

[frenchman]

Progressive spring helps with the linear leverage ratio. I’ve got a progressive valt spring on an ohlins in my alpine. Goes good.
Accept that there are better bikes with more capable suspension design.
I also live for the moments when I smash the bumpstop.

 

[the drizzle]

I rode my single pivot marino with a coil shock and was a bit worried how it would go in the anticipation leading up to the build, but it was fantastic.

The shock probably helped a lot too, it was an ext storia V3 so had hydraulic bottom out.

Sent from my Mi 9T using Tapatalk

 

[beeb]

Damn all you helpful people!

Where's all the "Pfft, no chance it'll work you idiot!" voices?

 

[wkkie]

Damn all you helpful people!

Where's all the "Pfft, no chance it'll work you idiot!" voices?

You know that was never going to happen! Way too many enablers in here!

 

[leitch]

@beeb

 

[shiny]

So @beeb EXT Storia, Push 11-6 or Formula Mod coil shock.....

 

[beeb]

The Push 11-6 has always been my particular fetish in the high-end crowd. Not sure I can put an aftermarket progressive coil on one of them though, and would honestly be happy with a Rockshox coil shock.

 

[gillyske]

i ran a rockshox rct coil on my commencal meta and found that whilst it never offered the exact same performance whilst pumping or boosting, I never ever got bucked for no fucking reason. Also it was smooth as butter compared to the rs super delux air, which was... fine but theres something about spending multiple thousands of dollars on a bike... it should feel like it? A coil makes it feel like you're riding on big money all the time.

Switched to coil on my Merdia E160 (also single pivot) and compared to the DPX2 I can tell I'm sorely underpsrung off the top stroke. I got excited and chucked a 450-550 CC vault on it based on recommended charts. Took it to Bright/FC and found that it just didnt support me the way the DPX2 or the rockshox rct coil on my commencal did. I had to put the x-fusion HC3 into its 2nd position and add more LSC to get it to not blow through its travel constantly Edit: Blow through travel isn't correct, basically it would just be very eager to quickly move to the end of the stroke (it wouldn't bottom out), being completely absent at the begining and then kinda leave you wallowing in the middle without any kind of confidence or support. Have a 500-610 on order to see how that goes. I have faith that this single pivot coil will come good as this is exactly what happened on the commencal anyway.

 

[rangersac]

X-Fusion vector on my Cotic Rocket. Feels endlessly plush, and I don't think i've ever bottomed it out despite frequently riding like a spud. Definitely takes more effort to get airborne than an air shock, but for plowing gnar there's no contest