I am currently putting together a wish list for a custom frame. I’ve noticed the trend at the moment is for short stays on a 29er but from all the reading I have done on-line longer seems to be better.

Santa Cruz and Salsa are knocking out 430mm stays but from what I can see somthing in the region of 435mm will make the bike climb better and be more stable at speed.

What are peoples opinions?

Define better. FWIW, I don’t reckon most people would notice 5mm difference if you didn’t tell them.

I’ve been riding bikes with similar reach and HA but the bike with 447mm stays is actually more fun. It seems to climb better both seated and standing.

What does “climbs better” mean? If it means less likely to wheelie on a climb then yes, chainstay length would be part of that (along with seat angle, etc)

IMO it won’t make a big difference, I’ve the older El-Mariachi with slightly longer stays and they’re not ‘too long’ except on paper.

Whereas my Fat Bike is too long (despite being an on-one which is quite short IIRC), you can feel the rear end/wheel pushing the bike upright as you turn into corners.

To get so short that it affects stability would take some doing on a 29er, I think on a Large sized frame the average 29er’s stays with enough clearance for sensible tyres is perfectly balanced.

If I was getting a custom frame made I think chainstay length would be minimised, but secondary to having good clearances. And there’s a lot more details I’d obsess over beyond geometry, like bottle cage mounts in unusual places for additional storage, cable guides where I want them, getting it perfectly fitted with an inline post etc. The basics of stuff like geometry I think the big brands have got pretty much nailed and they’ve had the facilities to do many prototypes, definitely better than you could make up when you’ve only got one shot at it.

435mm is still pretty damn short for a 29er. The pros and cons of 430mm vs 450mm might make for an interesting debate, but 430 vs 435 is splitting hairs really.

Got a sliding dropout 29er and can certainly tell differences in the chain stay length, for me it affects the way the bike handles a far bit as well as how it climbs. I set it up short for tight stuff and long for longer days out, it’s a ti frame and I swear I can tell comfort wise when the chain stay is longer. However if may all be in my mind, but good enough for me. Any chance can get built with sliders ? Love mine, no issues and can SS easy.

I’ll bet you couldn’t tell 5mm difference if no one told you.

I’ve had several frames with sliders and never noticed any significant difference regardless of where they were set.

We are all different, I’m fairly sensitive to set up. Been racing mtb on an off for 20 yrs, ride motorbikes and generally like to experiment. Done plenty of blind tests over the years with adj head angles, tyre pressures etc and understand that one change affects the whole. All I was suggesting that adj dropouts could be an option as there may be no right answer. As I say it may be all in my head 😉

Only having a frame made as I want titanium with a certain reach that’s not available off the peg without a silly standover.

I intent to used Pact as have faith he will know exactly what he’s doing. The chainstay lenght was more me being curious as to impacts.

I intent to used Pact as have faith he will know exactly what he’s doing. The chainstay lenght was more me being curious as to impacts.

Brant’s discussed chainstay length on here before http://singletrackworld.com/forum/topic/why-doesnt-chainstay-length-change-with-frame-size

And his bikes have (rarely, the fireline is pretty short) had slammed chainstays, in fact until 29ers came along, they were often unfashionably long!