nyubie

Hi All,

Just wondering, why it's only limited number of Frame Builder do custom full suspension frame? I know some small company do that, like Seven cycles etc but not individual one-man builder. Is it related to patents on the geometry? Or is it very difficult to fabricate by manual method?

Thanks

MichaelW

Maybe the R&D effort of getting the suspension just right are too much for a one-off.
People fabricate complex machines such as recumbents and trikes.

Ignatz

There are some small and one person shops making full suspension frames; Inglis, Curtlo, Sycip, etc. They buy rear "triangles" from larger manufacturers and make custom front triangles. I'd imagine it's a matter of not having the machining resources to make the swingarms.

Thylacine

Making a frame by joining a few off-the-shelf parts and tubes are one thing. Making a full suspension frame where you have to make EVERYTHING except the tubing youself (including the jigs to hold eveything together) is a whole other kettle of fish.

Basically, very few guys have the resources or knowhow.

I started Thylacine Cycles with an FS bike.....currently evaluating a few ideas for a new one....we'll see what happens. Doing FS bikes is 20 times harder than hardtails, and I ain't exaggerating.

nyubie

Thanks Thylacine,

I visited your website and impressed with the design I saw there.

CMIIW, but because most of the frame builders do on steel tubes, I guess the difficulties lies on fabricating (CNC, etc) of yokes, rocker arms of pivots and links. Steel is harder than Alu when you CNC those bits and pieces.

I remember small company producing steel full sus but can't remember their website. They have DH frame as well as XC. I'll post the link if my search hit the link.

Thylacine

There are ways around that, you just have to stop thinking about how you'd accomplish something in Aluminium and start thinking in 'Steel', so to speak.

Theres a few people doing some form of steel in their FS bikes - Vicious, Sycip, Balfa, Brooklyn Machine Works, Ted Wojik (sp)....I'm sure there are others.

tomacropod

is Ethos bicycles in Canberra still alive Warwick? I believe he was an engineering graduate and had a very clever design. Super efficient rear suspension for XC >>> DH. Aluminium frames.

Perhaps I should know, I live in Canberra...

edit: Google knows:

https://www.ethosbicycles.com/ethosbicycles_about.html

he lives in my area too by the looks of it...

- Joel

Thylacine

Not sure about those guys. The ads are still in AMB, so I'm guessing they're still around. Last time I spoke to them was at the 2002 BITS Show where they were showing a beefier looking bike, but I wasn't sure how the bike differed from any other four-bar bike out there.

tomacropod

the left and right lower swingarms (forgive terminology, I don't have any experience with duallies) are different shapes and I think the pivots are in different places as well. The right-hand swingarm's pivot is actually in front of, and above, the BB.

I think the fact that they have been doing that four-bar design for years (whereas production bikes have only been using it to full effect recently) is the reason they have the reputation as great engineers (plural? It's just one guy - it's ALWAYS just one guy despite the plurals on the site ). I'm not sure if that counts for anything though.

- Joel

Thylacine

No, they've just aligned the pivots with the chainline in the middle gear, and the "one up, one down' Chainstays aren't new - my 1994 Mantis had that, and so do the latest lightweight Turners, Ellsworths etc. Neither of these things are amazing engineering feats, which are a good thing. Major feats tend to scare customers off unless they're simple for Joe Mountainbiker to understand, or if not, you better have some good marketing in place.

As to the 'plural' thing, Ethos is actually 2 guys, or was last time I spoke to them. I'm a sole trader and use plural, simply because 1) I'm now married, and 2) No man is an island, and without quality sub contractors, you ain't going nowhere, so it's nice to recognise them. It also helps you punch above your weight, which is always good

PaPa

Although not a custom builder, (to the best of my knowledge) I'm surprised John Castellano's name hasn't appeared yet. From a personal prospective, I favor intelligent passive - but achieving it before the shavings start hitting the floor, is quite another matter.

https://www.castellanodesigns.com/diff.html