[Closed] Lets talk about chainstay length

6ft 3 here and in a similar position.

What new bikes are you considering?

I was kind of surprised to see Santa Cruz (who were longtime evangelists for the short chainstay) adopting variable length chainstays for the new 5010 (which is their short-travel play bike). Seems opinion is turning on this one

read the nico voillioz interview on pinkbike. i like what he says. basically long is straight line fast but you sacrifice fun. its bloody good article/interview.

I suppose you need to think about your riding and what you want it for (racing/pottering/jibbing/DH)

510 reach 440 chainstay on a 29er, plenty of agility for me (in fact the most agile 29er I've ridden).

read the nico voillioz interview on pinkbike. i like what he says. basically long is straight line fast but you sacrifice fun. its bloody good article/interview.

It is a great interview. But I think you could make all sorts of arguments based on his pearls of wisdom.

I thought he was talking more about overall frame length, and saying that long bikes are more benefit to us punters than to riding gods - who might sometimes be quicker on a shorter frame.

I'm 5ft 8in and my preferred reach/chainstay lengths are around 460mm/450mm, for general riding. It's still fun, because it's an Orange.

Have you seen the new Stage 6 OP? It has 469mm chainstays and more than 500mm reach on the XL.

There's an enduro-mtb test of 3500EUR enduro bikes, section on perfect chainstay length was interesting about the ratio to front centre mattering more than the length.

The first thing here to take notice is that chainstay length should not be compared to reach but rather to front center length. You can have two bikes the same reach but greatly different front centers due to different fork travel and head angles.
Then, to put things in perspective, 3 or 4 years ago a typical size L enduro 29er would have something in the lines of a 66° HA, 450mm reach and 150mm fork, while today a typical one could be 64,5° HA, 490mm reach and 170mm fork. The front center went from about 760mm to a whopping 833mm in these examples, a huge 73mm difference. This while the reach "only" grew 40mm.

What zezaskar said.

As a bad example, early 29ers, Xc up front, long chainstays out back, they felt like the back end was turning in at a different speed to the front, like it's trying to push you upright, a bit like dragging the back brake.

As a good example, the new Scandal, it's not massively different to the Parkwood, but the front end is slacker and longer, and subsequently it's suddenly much more balanced.

It's not the chainstay length that matters, but how balanced it feels with the front of the bike.

Have you measured the S150 chainstay length? I can't remember off hand but it's longer than the 435 claimed.

I have a short travel 29er full sus with a 430mm rear and it does make the bike more agile and fun to ride for me. On really steep climbs longer stays help hold the front of the bike down. I also have a cross bike with a 425mm rear and that does feel a tad too short at times, usually climbing. I think with longer, slacker, lower bikes the idea is you lean the bike over more to corner so chainstay length doesn't play such a big part in that anymore. It's all a balancing act.

My hardtail has 420mm chainstays and a 1185mm wheelbase - it’s a lot of fun but it isn’t the easiest bike to handle when you try to go flat out, the back end is quite twitchy. My full-sus has chainstays that are 35mm longer but the wheelbase is only 45mm greater - it’s so easy to two wheel drift and ride on the ragged edge. But it’s definitely far less flicky and you have to move more to manual it.

I'm also an XL rider. The way I see it is the original design factors in a chainstay length that is in proportion to the bike as a whole and what it is designed to do. Particularly with regard to front centre as mentioned above. That being the case as frame sizes change, the chainstays should change as well in order to retain the designed proportions. If they don't then that's going to change the handling characteristics from the original design brief.

Some brands (Norco spring to mind) have been doing this for years. Its good that Santa Cruz have seen the light.

Onto handling per se, longer stays mean better straight line stability and better climbing as the rear wheel will dig in and grip more on loose stuff and you'll get less front end lift on the steeps. What you lose is flickability through tight corners as well as more effort to get the front wheel in the air.

At the end of the day, if all bikes are designed around a medium-large frame, then the vast majority of XL bikes out there are more flicky and poppy (and consequently worse climbers and more unstable) than they were designed to be, assuming that the stays haven't been lengthened. Not that I'd necessarily be able to tell the difference mind..

Have you measured the S150 chainstay length? I can’t remember off hand but it’s longer than the 435 claimed.

Hmm I just measured it out of curiosity, BB to axle is 440mm, but from the axle to above the BB in a horizontal line is 435mm. I guess I've just stumbled across the subtle difference between rear centre and chainstay length just to muddy the waters further..

I guess I was really asking the question of whether tall people find short chainstay bikes a little unbalanced, take that new commencal meta 29, with a 520mm reach and 63.5 HA makes for a huge front centre, then a short 433mm chainstay length?

Does those sort of numbers make the bike feel unbalanced, or does that turn me into a schralping legend?

The first thing here to take notice is that chainstay length should not be compared to reach but rather to front center length

Yes front centre and rear centre are more useful when thinking about the balance of the overall wheelbase, but I don't compare reach to rear centre - I understand that they are the two most influential figures in how I experience a bike's handling, and consider them both as part of an overall package.

As bikes get longer in reach generally, and enduro bikes tend to all be pretty slack, it's the rear that sees the most variability between bikes, proportionally.

So I’ve always played around with bike setup a fair bit and definitely a fan of the whole long low and slack set up. For reference i’m 5.9” on a good day but tend to ride a large in most size frames with a short (32-40mm) stem. I use to run a large banshee spitfire with 27.5” wheels but in with 26” dropouts which I really liked (fun and poppy but with the length for ploughing at speed). I swooped the frame out to a Longer (medium) nicolai geomatron mk1 g16 which really pushed the length Of the bike (500 reach) but also chainstays (445). I find the chainstays too long for how i like to ride (the mk2 and g1 have the ability to change the length with different chips). I’ve also got a Marino steel hardtail with sliding dropouts which are set in the shortest setting. I think the mix of long front and short rear (with low bb) helps to make a fun bike but safe for me.

Hello Dave has huge chainstays and rides beautifully

I guess I was really asking the question of whether tall people find short chainstay bikes a little unbalanced

Yes, I do...

Only realised this with my last few frames and now only buy if the chainstays are suitably long enough to match the rest of the bike.

One of the nice things about longer chainstays is that for a given saddle height you don’t need as steep a seat angle to be able to climb really steep stuff sitting without pulling wheelies. And seat angles that aren’t so crazy steep make for a better pedalling position on the flat or less steep climbs, or undulating trails where you move in and out of the saddle repeatedly.

Here’s another thing to consider - if you have short legs and a long torso your longitudinal hip position will be further forwards than someone of the same height with long legs and a short torso. So the long-legged rider has more leverage from their hips and will find it easier to flick about a bike with long chainstays.

I guess I was really asking the question of whether tall people find short chainstay bikes a little unbalanced

Definitely, I am 6ft4 and had an XL Transition Smuggler which is 430mm stays, it was a great fun bike but I always felt like I was hanging off the back on climbs.

I am now on an XXL Last Glen, 445mm stays, longer reach, the bike feels alot more proportioned, I feel alot more centred and I wouldn't say it really feels much less manoeuvrable than the Smuggler. It just fits me alot better!

Would recommend a look at Last, they use proportion chainstay throughout thier range.

I'm the opposite to most of the above. I ride XL HT frames and I love short chainstays.

I've had a Chameleon 415mm and a Cotic Solaris 444mm. I liked the Chameleon much better, but I like to jump off stuff and throw the bike around.

My current bike is an RSD Middlechild Ti with 415-430mm chainstays. It wheelies, manuals and jumps really well but is less planted at speed or on steep climbs in 415mm mode. I'm happy with that, but I can slide my dropouts back to 430mm if I feel the need.

Neither long or short chainstays are wrong - its a choice of how you like you bike to handle.

https://reebcycles.com/bikes/mountain/redikyelous/

The Reeb has a chainstay length of 408mm now thats a short chainstay on a 29er with 2.6s:-)

I guess I was really asking the question of whether tall people find short chainstay bikes a little unbalanced,

nope. it depends on your preferance. my HT is longer reach so it is quite planted even with 160mm forks when climbing. it was great at BPW going fast. Its a bit too big to be really fun locally if i`m honest - its fine and compentent but not massively engaging - more monster truck. my old medium eccentric was a way more fun bike locally but i wouldnt have taken it to BPW.

the issue with short stays was back when we had slack seat angles and short top tubes. longer reach and a steeper seat angle resolves many of the issues.

Enigma said: “ Is this just a cost thing and short stays make a long bike less balanced, or do long chainstays make an XL enduro bike too much of a barge?”

Yes to both.
Yes, it is cheaper for brands to keep the same chainstays.
Yes, long chainstays on a bike that is very long in the front, will make for a super duper long bike overal, which might have it's drawbacks in certain situations (most noticeably on skinnies with a corner in them, to a lesser degree tight, low speed switchbacks).

I still think that proper handling and balance is the most important, and we(tall folks) just have to deal with the drawbacks of a long wheel base, as the benefits out weigh the drawbacks.
.

Incorrect weight balance front to rear screws up everything:
Climbing is harder, because your front wheel wanders and your rear suspension sags even more.
Descending cornering (on everything not crazy steep) is harder because you don’t have good traction on the front wheel.

It is however why I personally search for a different solution:
I need pretty long reach (>520mm) for proper fit.

So I chose a slightly steeper head angle than is becoming popular (67*), but with a super short offset fork (37mm) on a moderately large wheel(27.5x2.8), this yields a plenty high trail number (114mm), for my trails, which are not super fast.
Similar to a 65.5* HA 29er or 27.5 with standard offset forks.

The short offset fork also brings the front wheel in a bit more too, so, combined with the not to slack HA, the front center is not crazy long, despite the long reach(527mm).
So, this can then be combined with a moderately long chainstay length (440mm).
To get the same front rear/weight balance with a 51mm offset fork, I’d have a waaayy longer wheelbase.

Mattvanders said: “ think the mix of long front and short rear (with low bb) helps to make a fun bike but safe for me“

The key there, is that you are a short rider. It is different for tall riders.
Of course, everyone finds it easier to manual a bike with short chainstays.
But, a 5% taller rider, can manual a bike with 5% longer chainstays just as easy as a short rider on a short bike, because their center of gravity will be in the same spot relative to the rear axle.

The other thing is, you are riding a frame that is quite long in the reach, in relation to your body size. So naturally, you would find it harder to get your weight back for manuals etc.

In other words, a short rider(5’9”) on a bike with a fairly long reach(500mm), is a very different situation from a tall(6’2”(OP), or 6’5” like me) rider, on a bike with 510-530mm reach.

my hardtail is longer reach and short stays and isa 'a right bugger to manual' as described by a very good old bmx rider. longer stays will only be harder.

I'm 6ft on the nose riding a large Dartmoor primal 27+ - 420MM chainstays 450MM reach so not even that big in relation to some of the numbers in these conversations. I'd not want a bigger HT - even for BPW or similar.

Its about personal preferance and, probably more importantly, where you ride. If i lived in wales or the alps i'd have a geometron. but i dont, i live in brighton on the south coast so a smaller more fun bike is more relevent to get the most from the (fairly lame) trails in the locality.

be honest about your riding and whether you want stability (long stays) or fun (short stays). life is a compromise always!

Just to confirm I'm tall at 6'4" and would prefer a longer front and shorter rear in most situations to keep the bike fun and agile. I've not found that makes a bike feel unbalanced once used to how it rides and where to position rider weight. That being said in the greater scheme of things 430 isn't really that short, some bikes now and loads of 26ers used to be much shorter. 440-445 isn't so very long either, many early 29ers were 450-455 or longer. Somewhere in that range there might be a chainstay length that's spot on and goes totally unnoticed out on the trail. I had a bike that was 437mm and never thought about it. Since the new Meta AM 29 got mentioned the geo looks ideal to me for schralping. The steep seat angle should take care of any short chainstay related climbing issues, although potentially at the expense of seated cockpit length.