True to a point, though if the fork is supporting weight that’s heading fwd and down it’s inevitable you’ll get some compression that pitches you fwd a bit.

Not entirely true either though.

If you shift your weight onto the front wheel, then the front fork compresses – yes

If you shift your weight onto the front wheel, then the rear shock extends – yes, but only on a FS.

So a hardtail get’s steeper going downhill, but not by as much as a FS. There’s some interplay of the relative axle paths which probably means the fork compresses more than the shock extends, but that applies to both bikes.

I saw the title and knew @chiefgrooveguru would have a view :-)

But I’ve just learnt something…

a full-sus bike’s geometry changes even more whilst riding: Point a 160mm hardtail and a 160mm Horst-link full-sus down something steep and then brake and the full-sus’s fork squishes down as the back end rises whilst on the hardtail at least the back end stays put!

I’d always just taken it in as a disadvantage of a hardtail vs full suss but this makes complete sense.

It’ll depend on how modern the geometry is and how good the forks are. 10-15 years forks tended to either blow through their travel or be too stiff to use all the 160mm and bikes were shorter and steeper. A fork with decent midstroke support will help.  The only real downside is the front writing cheques the back can’t cash, but a lot of that will come down to technique.

I’m currently riding a Ragley Marley with 140mm travel. To be honest I’m still getting used to it and getting it dialled in.

It’s great for hooning around on and makes riding in the UK much more fun. I’ve ridden some reasonably gnarly enduro trails on it.

But so far I’m struggling to use all the travel at the front, so I was wondering whether 160mm travel plus added anything to the recipe?

It all depends on what you like doing, I had this S!ck Wülf set up with 27.5+ wheels, 2.8” tyres and 170mm Yaris and it was an absolute riot,

I very much liked pointing it downhill and smashing into stuff.

whereas I also had this Big Dog set up with 150mm lyriks and I didn’t enjoy it nearly as much because as much as I tried just to be a middle aged mountain biker with “an edge”  I kept riding it like I was on a DH bike and didn’t get much out of it. It wasn’t even especially average with the 130mm forks that came on it.

So basically some are good and some are bad, but if you get the chance to ride a 62° head angle hardtail with a low Bb and long back end, and long forks give it a go because they’re epic

I don’t like long travel forks on hardtails. Or more accurately, I don’t like soft forks on hardtails.

I think I’m currently running somewhere between 10 and 15% sag on 140 forks and realistically get 110ish of travel.

Any softer or longer and the bike feels unbalanced and I get sent forwards when I push hard into fast steep berms or compressions. On a bouncy bike the whole bike compresses and stays balanced in these situations. On a hardtail the back isn’t moving and the bike feels wrong with long saggy forks.

Bad technique, personal preference, riding style, dunno. I ride pretty much exclusively hardtails for everything from xc to dh and that’s where I’ve ended up.

(edit – I find most bouncy bikes sluggish and unresponsive unless they’re pointing down something steep, so it’s probably just me.)

I find most bouncy bikes sluggish and unresponsive unless they’re pointing down something steep, so it’s probably just me.

I’ve got an awesome full sus, and a cheap(ish) hardtail. It’s the hardtail that I’m getting excited about riding in the UK.

I had 170mm on my last hardtail and didn’t like it, just felt way too much and really unbalanced and divey. Could be a setup issue but even set up with more support I didn’t love it. Kept meaning to reduce it to 150mm but never got round to it. It was also a kind of older geometry hardtail so wouldn’t mind trying it on a newer one to see how that changes things.

Generally I like the more balanced feel of a FS but I can’t help but keep going back to HTs for the simplicity and more direct feel.

I had a Cove Stiffee with forks from 100 to 130mm. It worked best with 110mm.

My current Sick Shrike- the one that was rebadged and the On One Hello Dave- is awesome with 160mm. I’ve tried it at 150mm, but there are even more pedal strikes and it just wasn’t as fun.

I’ve done a lot of sliding round my local woods, the odd 50 mile ride in the peaks and the odd bike packing ride. Mostly on 2.6 tyres.

So for me, there are no downsides to 160mm forks on the right frame.

The cove was awful going up on 130mm forks and ace on the way down. I solved that with adjustable recon coils.

a full-sus bike’s geometry changes even more whilst riding: Point a 160mm hardtail and a 160mm Horst-link full-sus down something steep and then brake and the full-sus’s fork squishes down as the back end rises whilst on the hardtail at least the back end stays put!

only on a horst link or some other sus design with a floating rear brake caliper. On 4-bars, single pivots and the like the braking forces on the rear of the bike work to compress the rear shock, and in fact anything with a rear-ward axle path (even horst link) will also try to compress the shock due to forces pulling the rear wheel rear-ward.

even on a full sus bike with a horst link, I’m not sure what you stated is true, assuming you run the same amount of spring rate/damping in the fork. On a hardtail your weight can only pivot around the rear axle, as that’s the fixed point. on a full sus bike, it pivots around some vitual point in the middle of the bike as both wheels move independently. However, for a given amount of braking force and a given amount of gravity, the cog of the rider supported by the suspension will be at the same height. So *if* a full sus bike raised its rear up, it should be that the fork compresses less (same amount of force, but levered over a smaller point as the pivot point is further forwards), thus giving you more fork travel remaining to deal with bumps.

“only on a horst link or some other sus design with a floating rear brake caliper. On 4-bars, single pivots and the like the braking forces on the rear of the bike work to compress the rear shock, and in fact anything with a rear-ward axle path (even horst link) will also try to compress the shock due to forces pulling the rear wheel rear-ward.”

The rising of the rear suspension is only counteracted by the anti-rise generated by the torque at the rear caliper – it’s highest with a high single-pivot and lowest with a traditional Horst link but whatever you do, the front brake is doing more of the braking work when it’s steep, particularly when it’s loose or slippery, so there isn’t enough torque at the caliper to pull the rear end down. And if your weight shifts onto the fork, either because you’re going down something steep or because you’re braking, or both, then the laws of suspension means that the rear suspension will try to extend. Hardtails don’t extend at the back!

I’ll have a think about your other point…

But more relevant is the fact that nowadays I swap between two MTBs – a Levo electric full-sus that does commuting (fun and boring ways), lapping steeper stuff and away trips, and my Moxie singlespeed that does most of my local riding. This is the first time I’ve ever been able to hop between a full-sus and a hardtail and be totally comfortable and I think a lot of that is down to me making them as similar as possible. The sagged geometry is near identical bar the Levo swapping ~20mm less reach for ~20mm more chainstay and they’re both running a 160mm Lyrik RC2.

Logically I think this bike is absolutely stupid but in reality I think it’s bloody marvellous!

I’m back on a 150mm one (Titus Loco Moto, ie titanium Big Dog) after a spell on a solarismax and tbh if I could wave the magic wand, I’d make it 130 or 140, I think it’d just simply be better for me. I didn’t think the extra travel was bringing any benefits for me, mostly because a good 140mm coil fork is so damn effective anyway. But equally it’s not causing any big problems.

Solution I reached was to tune the fork so that it’s just not using the full travel- I have the full range of performance I want in the top 130mmm or thereabouts, and it doesn’t bottom out (perhaps it will at some point). Not an option with all forks of course and it took some effort but it’s definitely the best the bike’s ridden, it’s gained a little predictabity and composure at speed and on hard braking (most noticable when I screw up!) and I don’t really feel like it’s lost anything of worth.

Not really sure if there’s any useful takeaways from this! Obviously it’d be better to get to the end result I’m at just with less fork, it’s stress the frame less and it’d be achievable with a less tunable fork. I mean, even if I had my lovely modded 36s from the other bike in it I would not be as happy, since they’re great but I couldn’t do this sort of setup hack with them. I guess it boils down to “this bike is more demanding of forks than it has to be”. Or maybe even “it only works as well as it does for me because of pure luck in my fork choice”

It is bloody brilliant though. Even if I was making do with a Pike or something, I’d be way less happy with it but it’d still be really good.

Still tinkering with the Lyriks on the Big Al, but have set them up slightly firmer than I normally do. Will be adding a token or two as well to ramp them up at the end of the stroke.

So I was out on my hardtail earlier today (not early enough because I was in the dark most of the ride) and I got thinking about how a hardtail works (and my 160mm Moxie singlespeed was working really well!)

We’re only touching the bike at four points when we’re riding downhill, the two grips (ok, and brake levers) and the two pedals. The grips are roughly the reach ahead of the BB, so in the case of my Moxie that’s about 470mm (the stem pushes them away but the spacers and bar shape brings them back). So if we look at how the rider’s hands and feet feel the forces, we could say we’ve got:

160mm of suspension at the front axle
118mm of suspension at the grips (305mm back from the front axle with a 1230mm wheelbase)
57mm of suspension at the BB – ie pedals (435 forward from the rear axle)
0mm of suspension at the rear axle

(Basing that on the rear axle being our pivot point – although it’s more accurately the rear contact patch).

So that’s from the rider’s perspective. From the wheels’s perspective we could think of the bike being a seesaw around the BB as that’s where most of our weight is applied, so the front wheel has 160mm of suspension whilst the rear wheel has 57mm of suspension (rear wheel goes up, bike rotates forwards around BB squashing fork down).

I know this is all quite imprecise but I think it gets closer to the truth of how a hardtail behaves (and feels!) than thinking a big fork hardtail has lots of suspension at the front and none at the back. It’s important to note that wherever the effective travel has been shortened, the suspension stiffness for that travel has been proportionally increased.

I’ve got a bandshee paradox in XL with 150mm on 29 wheels. I think for this size frame it’s great and feels good but I wonder what that set up would be like on a smaller frame. It climbs well despite wondering if it might be a bit wandery when I first got it.

Assuming the frame is more or less designed for the length then IMO the only real disadvantage is possibly not having the ability to lock out the fork when hucking up a climb 

From the wheels’s perspective we could think of the bike being a seesaw around the BB as that’s where most of our weight is applied, so the front wheel has 160mm of suspension whilst the rear wheel has 57mm of suspension (rear wheel goes up, bike rotates forwards around BB squashing fork down).

Agreed, as in my earlier post I do think this happens and to a more noticeable extent if you have a longer fork and a more neutral rider position. The ‘looser’ the bike is underneath you when riding through the rough the more it happens. 

Logically I think this bike is absolutely stupid but in reality I think it’s bloody marvellous!

Looks like a lot of fun.. SS is great when you enjoy the flow of using the bike to generate or keep speed and aren’t as focussed on absolute speed. I know clutch mechs have solved a lot of the old chainslap issues now but for a long time I also really appreciated the totally quiet drivetrain compared to the alternatives.