Return of the E-stay?

[danson67]

I came across this fat-bike E-stay being built by Whit Johnson at Meriweather Cycles:

I have long thought that they should be due for a return, specially in fat bikes, where tyre and crank/chainstay clearance is such a problem.
Combining smaller front chainrings, double or even single chainsets, fatter seat tubes and low mount front derailleurs is should be possible to overcome a lot of the problems we had before, and gain back the short chainstays and good mud clearance.

Any views? Any other new build e-stays, particularly not fat bikes?

All the best,

 

[mrkawasaki]

I am in the process of 'designing' a bike frame for fun, albeit specifically for bike polo, using elevated stays as an integral part of the solution. Polo bikes need a short wheelbase for slow speed agility and most custom designs use a curved seat tube to realise this, pulling in the rear axle with shorter stays.

Most early e-stays seem to have a bad reputation for unresolved frame failures where the chain stays meet either or both the seat and the downtubes, or at the axle end of the stays. I'm no engineer, but it occurs to me that the chainstays must act as a long lever or see-saw on rough terrain, leading to big repetitive stresses at those welded points and eventually failure, especially when using aluminium. I am also mindful of the effects of too much heating/welding in any area and the weakening of tubes by piercing - hence I hope to use a single piece looped chainstay to minimise 'twist' at the axle, with a billet wedge to be seam-welded to the otherwsie-intact seat tube and creating a larger intersection with the bottom bracket shell. I hope my solution addresses another oft-levelled criticism of e-stay design, that the bottom bracket was less stable under power too.

I do wonder whether contemporary builders have considered or learnt from past failures? Do they swap notes and experiences? Having said all that, I have had over 10 e-stay bikes in my time and none have failed yet (although most are steel).

 

[epicyclo]

The biggest problem I had in my limited experience of E-stays was the twisting flex between the BB and the rear axle.

That was only a problem because I was trying to use it with belt drive, and there was a simple enough solution.

The bike pictured above looks like it won't have that problem with the wider bracing for the fat tyre. I suspect that E-stays are the answer to the chainstay problems that fatbikes have.

This one is mine and I have been considering widening it for fat tyres:

 

[MikeD]

Ade Ward (formerly of Whyte/Marin) makes these:

 

[Exeter Man]

Thought that looked familiar - featured here on the Spanner Bikes blog:

http://www.spanner.org.uk/2011/12/galle ... r-by-xacd/

Had a really good read through the blog a few weeks ago, and found it most informative and interesting.

Regards

 

[gunner]

I like it from a practical perspective but not so much from an aesthetic one...

 

[Woz]

The one thing that put's me off with fat bikes is the wide BB shell and associated wide Q-factor. I see the E-stay design for Fat Bikes is a good thing. An E-stay design with disks, vertical drop-outs, single small chainring and a 11 speed gear hub with a small 12T sprocket set to an appropriate magic gear would be my preference. When the chain "stretches" it can be replaced very easy with an E-stay design; chains are cheap enough to replace often (and it's good practice if running AL chain-rings). No need for tensioners or more complex drop-outs. That Ade Ward looks pretty right in my eyes (except 2.4" isn't really Fat).

Can we really compare the E-stay stresses of old when we were running skinny 1.75 or 1.95 at higher PSI to these all shock absorbing 3" - 4" low PSI set-ups? Would BB flex really be an issue when surely the tyre side wall flex will be much more? Is a Fat Bike really the tool for maximum power transfer and stiffness to begin with - as they are not built for speed, but rather go anywhere so flex would not be a big issue?

 

[coomber]

Love the old e stays. Some of these here look great.

Can see it being a good problem solver for fat bikes. For 29ers and below etc the fact clutch rear mechs are down to deore level means chain slap/ chain suck should be less of a problem ongoing.

Somebody on here built their own 29er and it was brilliant. Will try and post the link when I'm not in my phone.

If any of you want to build a prototype I'll happily test it!