Viewing 22 posts - 1 through 22 (of 22 total)
  • Why not build FS in steel?
  • geetee1972
    Free Member

    Just recently there have been a few FS bikes popping up that are made from steel – Superco has DH bike (their connection with Brooklyn would explain why it’s steel) and K-9 industries are about to launch a DH bike in steel. And o course there is Brooklyn with their esoteric (and exotic) Racelink.

    Now time was when steel fell out of favour because it couldn’t be made light enough and stiff enough to compete with aluminium. By the time you got to a reasonable weight reasonable stiffness frame, the tubes were so think they were prone to crushing and denting. The original Sunn Radicals were I think made of steel, but that was when the weight of a DH bike was less of a hot topic.

    Now, the Superco DH bike is being billed as weighing 37lbs, which is pretty remarkable. The advent of new forms of steel alloys like 853 and 953 have heralded a new age of steel hardtail frames but not FS frames.

    So, why not make FS frames out of steel? Is it just that everyone has tooled up for aluminium; perhaps there’s just not any advantage to be had; do they still have a weight penalty/stiffness penalty (depending on how you use it) compared to aluminium?

    enfht
    Free Member

    also, why not more full suss ti frames? Surely the weight saving would make fs frames more appealing in ti than hardtails?

    VanHalen
    Full Member

    posh steel is more expensive?

    jfeb
    Free Member

    I was say an “average” 853 hardtail frame is heavier than “average” aluminium one (massive generalisations here!) so weight would still be an issue with FS frames. And what would be the benefit of a steel FS over an aluminium one?

    Olly
    Free Member

    compliance and springyness of steel is utterly pointless when youve got 8.5″ of super squish under you?
    where as alu is uber stiff, which is what DHers always seem to want (laterally)
    sure it may be possible with moder steel, but much more expensive for the same positives?

    cynic-al
    Free Member

    Alu is cheaper to make lighter and stiffer, and cheaper/easier to machine up pivot mounts etc (which are lighter)

    cheekysprocket
    Full Member

    ‘cos it’s easier to build a stiffer, lighter and cheaper frame from aluminium.

    STATO
    Free Member

    As stated above, the majority of the percieved advantages of steel over alu are outweighed by the disadvantages in most full sus application. There are some excetions tho, most notibly fatigue life and repairability. It is often claimed that steel frames are stronger than alu, however strength is something that can be built into an alu frame and steel frames that claim this are often designed to be stronger than their alu competition. eg. that is why brooklyn started with steel, their alu frames used to break under extreme riding, they could have built tough frames in alu but steel was easier to work with in a shop environment).

    Carbon and titanium are now also being used for sus frames. Titanium is similar to steel in that the percieved benefits are reduced when used in a suspension application. You will still find them tho as there are no real disadvantages compared to alu aside from cost(flex is often touted as a reason not to but good design should prevent this). Carbon is also popular now and the much lighter weight can provide some excellent oppertunites when designing a full sus, however the disadvantages (mostly impact resistance, failures due to disbonding should be a thing of the past in a good build/design) are often the reason most will not consider it, again tho, aside from cost.

    tinsy
    Free Member

    Litespeed made the Niota in Ti for ages, dont think they sold too many as it was expensive, lots of reasons to make frames from Ti other than ride quality, they tend to keep their looks pretty well being one…

    There is a British company also making cast alu frames too.

    doof_doof
    Free Member

    I’ve been toying with the idea of building a steel front triangle for my Turner, tweaking the geometry so it’s slightly lower and slacker. Even gone as far as modelling some of it in 3D CAD. I’ll get there one day…

    Inspiration comes from the lovely Fat City Shock a Billy

    aracer
    Free Member

    Very impressed with how carefully that is worded, STATO! 😉

    The real reason is that most buyers of full-sus bikes are more interested in the function of the suspension than the nicheness of the rigid bits.

    tinsy
    Free Member

    I want me some of those brown tyres…. (i know dont wash the ones I have)

    nonk
    Free Member

    they still do the niota dont they? and the short travel one is it the sewannee or somthing?

    nina
    Free Member

    xprezo make some nice looking steel fs frames

    thisisnotaspoon
    Free Member

    theres also a problem with allignment, no point making a great full sus frame if the flex pulls it out of alignment as soon as you hit the trails, resuling in bearings that last a matter of rides.

    I’m tempted to build a heckler esque bike with a second BB (with HTII cups) as the main pivot, then big alloy axel as the pivot. so in theory the alignment should be spot on and pretty stiff.

    slowmedown
    Free Member

    Darkside make some FS in steel, check this super heavy weight (repeat HEAVY) DH beast…

    bikesr4riding
    Free Member

    I’d understand the question if it related to Ti, but not steel. Why would you build an FS bike from steel? heavier, bendy, doesn’t work. Generally, manufacturers are looking to build bikes that are stiffer for better tracking and power transfer, whilst the front and rear shocks take care of the hits…

    squattingmouse
    Free Member

    Didn’t keewee make their DH bikes from steel as well?

    HTTP404
    Free Member

    keewee cromo 8?

    jimthesaint
    Full Member

    I had a Raleigh (dont laugh) full susser made out of 853 for the front triangle and something else (probably 531) for the stays. It had a horst link and a rocker driven shock.

    It was probably one of my favourite bikes of all time but as everyone else has already said it was heavier than its alu counterparts and the flex between the stays would wear out the horst link bushings in double quick time. When everything was working though it was lovely to ride.

    Steelfreak
    Free Member

    I’ve still got a Raleigh 853 full sus (chain stay pivots long since converted to phosphor-bronze). It’s had several powder coat make-overs over the years, but is still going strong (I think Emma Guy used to race on something similar).

    eviljoe
    Free Member

    I rode a mate’s Keewee in (no suprises) NZ, and it seemed to handle pretty good

    I’ve only recently put my ti full susser out to grass (antiquated urt design) and you could feel the springiness- particularly in the front end when climbing- climbed like a goat!

Viewing 22 posts - 1 through 22 (of 22 total)

The topic ‘Why not build FS in steel?’ is closed to new replies.