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  1. #1
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    29er Suspension design - XC/Enduro

    Folks,

    While I'm a) Holed up at home after surgery, and b) Not having ridden off-road in a year, I've been looking around at all the new MTB stuff for 2012 just to try and keep my hand and eye, in, as it were.

    As you're all painfully aware I'm sure, the only real option for custom builders is the Ventana rear end kit, which while nice to have, I do feel after taking stock of the market and available technology that straight four-bar designs are one evolutionary rung below VPP based designs.

    My heart has always ironically been with suspension - the first Thylacine was a 4" travel trailbike - so ultimately I've always wanted to do my own frame, but that's really just a pipe-dream.

    So I was wondering, what designs out there do you like at the moment? Do you think there is a market for a 'collective' design / rear end kit, only available to small custom builders?

    What do you think of the 'eccentric' pivot bikes, like the Yeti SB95 and Ibis Ripley?
    No longer member of the bike industry nor society, so don't hassle me.

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  3. #3
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    I saw that the guy from 18 Bikes is doing a steel single pivot design, which is great. Using the Cast Syntace dropouts too.


    Swingarm by 18bikes, on Flickr
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  4. #4
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    Is the difference in axle path worth the extra complication of vpp system over a single pivot design , or is it marketing hype?

    The main problem with simple single pivot designs is the failing shock rate , in the late 90,s this was easily corrected with the use of air sprung dampers which were rising rate but now with Modern air shocks being more linear rate , an extra link is needed to dial in the required rate change ,

    With a 29er wheel having less of a ramp angle than a 26 wheel the additional rearward movement of the axle path achieved by vpp designs may not be necessary ,
    Last edited by ade ward; 02-18-2012 at 01:07 AM. Reason: More info

  5. #5
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    Meh, what's a hinge or two between friends?

    A single pivot is inherently limiting because there is essentially only one variable - its location. More pivots, more tunability.
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  6. #6
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    Is that tunability for the builder or the customer,

    Not sure about giving the average customer too much adjustment, is easier to tune something bad than it is to get it right, like the cane creek 4 way damper , too much adjustment for most IMO especially as differences in high speed damping can't be felt by just bouncing on the saddle

  7. #7
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    I've ridden one of the original Outland Research VPP bikes and an Intense Spider. Yes better then any Horst link bike I've ever owned/ridden.

    Tim

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    Quote Originally Posted by TimT View Post
    I've ridden one of the original Outland Research VPP bikes and an Intense Spider. Yes better then any Horst link bike I've ever owned/ridden.

    Tim
    I what way were they better,

    I am not very good at feeling differences between bikes but I could feel the difference between an original single pivot and a single pivot bike with a shock linkage to get a slightly rising rate shock ,
    This was especially felt in dips and compressions as the bike didn't blow through it's travel

  9. #9
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    Quote Originally Posted by ade ward View Post
    I what way were they better, l
    Have you ever gone down a steep hill with a curve/turn at the end? The sharper the curve the more the bike can slide out. Didn't get that feeling on a VPP bike. Felt like the rear tire just stuck and went.Also noticed way less chain slap.

    Tim

  10. #10
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    A lot of it is marketing hype IMO. VPP/Multi-link/etc. bikes pedal well because they create a pivot point that is directly above or slightly behind the bb, and inline with the top of the intended chainring size (or somewhere in between chainrings in the case of bikes disigned to use front deraileurs), when sagged. The more rearward location of the pivot creates a more radical rearward arc, which increases chaingrowth, which increases pedal efficiency (though if you know how to pedal without hopping up and down on the pedals this becomes a whole lot less relevant).These things can be easily achieved with a single pivot design, though some sort of linkage will usually be required to negate a falling leverage rate, as was previously mentioned.

    Also, in linkage designs, the pivot point is constantly moving as the suspension cycles, horizontally for the most part. This creates what some have described as a "dead" feeling. Its because there is not a consistent point in which forces from the rear end are beeing input into the front triangle, and then percieved by the rider at the bb. For some i believe this creates an illusion of increased suppleness, even though the rear end is not doing any better a job absorbing bumps.

    Theres a reason theres still a whole lot of single pivot designs out there. They work just fine, and people still buy them. A lot of people still even prefer them.

    More to come later... need to get some breakfast.

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    A vpp multi link etc would have to be tied to certain points , as even a small change in pivot position can make huge changes to axle path or shock rate, Up to six points

    A linkage driven single pivot design would only require three locations swinging arm , linkage location and shock end eye to make a " kit backend" for frame builders

    I did a design for nukeproof for their scalp dh bike where the bb and pivot was on the same Cnc,d part so ensuring correct positioning and bores parallel to each other
    Last edited by ade ward; 02-18-2012 at 10:36 AM. Reason: More detail

  12. #12
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    Single pivots rock

    Random thoughts:
    -Very few people come to a custom builder for a super-high efficiency full suspension race bike.
    -Single pivots are very, very nice if you want to "customize" the geometry of the rear end (ie, bb height, CS length, main pivot location) without throwing the suspension performance completely out the window. You can't just start randomly moving pivots on a Horst/4-bar/etc setup willy-nilly. With a single pivot (especially low single pivots), things can move around a lot and still work fine.
    -Modern shocks can be tuned to the extent that suspension design is much less important than it used to be.
    -Single pivots don't tend to make noise, break unexpectedly, or require constant maintenance.

    IMHO the only problem with the Ventana kit is that it's a bit porky and a bit expensive. There's no patented/protected technology anywhere on it, so if someone wanted to design a new version with a few tweaks and mass produce it, I'm sure it would be popular.

    -Walt
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  13. #13
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    Quote Originally Posted by ade ward View Post
    Is the difference in axle path worth the extra complication of vpp system over a single pivot design , or is it marketing hype?

    The main problem with simple single pivot designs is the failing shock rate
    Re: Axle path. I never hear moto guys complaining about the axle path on their single pivot bikes, damping, chains, pinch flats and can I to un-break their broken forks, but never the axle path.

    I think it makes a difference on mtbs, but the amount it makes a difference seem to be hugely overstated. On a bike with a lot of travel it makes sense to help keep the overall wheelbase consistent and to help stop the rear wheel hanging up on bumps when it's deep in it's travel. But on a bike with 4in or less I can't see how you can get a useful amount of rearward travel without either using two chains or have a silly amount of pedal feedback.

    Re: Single pivots.

    I may be being dense here, but to me a falling leverage ratio is exactly what a bike should have. That way the ride is soft at the top, but ramps up the deeper into the travel you go. A big advantage of simple single pivots (to me) is that they tend to do that in a very linear manner without any sudden ramp ups or drop.
    My favourite thing about my Prophet is how it 'catches' you on landing from a drop, as opposed to simply blowing through it's travel. I nearly had a MK1 Nomad instead of the Prophet, but the way it would suddenly drop through the middle of it's travel like I'd hit a massive rock put me right off.

  14. #14
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    ^^^I think you're describing a rising rate shock. With a falling rate shock, it's initially stiff, then gets plusher as you go through the travel. IOW:

    Rising rate: the first inch of shock travel moves the wheel more than the last inch
    Falling rate: the first inch of shock travel moves the wheel less than the last inch.

    Or do I have it backwards? I can't tell right now since I'm tired from skiing and having a beer.

    I'll add one thought that I've mentioned here at some point in the past: I think it would be cool for components of a ventana style rear end (i.e. dropouts, pivots, yoke(s), rockers) that the builder welds/brazes together with choice of tubes.

  15. #15
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    Quote Originally Posted by Walt View Post
    -Very few people come to a custom builder for a super-high efficiency full suspension race bike.
    -Single pivots are very, very nice if you want to "customize" the geometry of the rear end (ie, bb height, CS length, main pivot location) without throwing the suspension performance completely out the window. You can't just start randomly moving pivots on a Horst/4-bar/etc setup willy-nilly. With a single pivot (especially low single pivots), things can move around a lot and still work fine.
    -Modern shocks can be tuned to the extent that suspension design is much less important than it used to be.
    -Single pivots don't tend to make noise, break unexpectedly, or require constant maintenance.

    IMHO the only problem with the Ventana kit is that it's a bit porky and a bit expensive. There's no patented/protected technology anywhere on it, so if someone wanted to design a new version with a few tweaks and mass produce it, I'm sure it would be popular.

    -Walt
    I kinda think that there is an emerging untapped market for performance full-suspension bikes - we're just not exploiting it.

    There's a couple of points here.

    Firstly, when I looked into licencing a rear end (ha) a couple of years ago as a point of difference to the Ventanas, the cost of the chainstay/seatstay parts were USD275, mill finish. Rockers and all pivots added USD114, making a raw cost of USD389. I can't remember how much OE shocks are, but I think about USD80? I guess everyone is getting the picture.

    Secondly, I'm sure everyone recalls the "Aluminium is great because it's cheap to machine and easy to manipulate blah blah blah" conversation as it pertains to full suspension frames, but do you realise 'modern' Aluminium 29er trailbike frames weigh on average 6.5lbs (3kgs)?!

    Dunno about you, but a heavy, large size 29er hardtail in STEEL weighs circa 2kg, so add 200g for a shock, and that leaves you with 800g worth of links and reinforcement? Seriously?

    Steel is real fellas, come oooooooon!

    No longer member of the bike industry nor society, so don't hassle me.

  16. #16
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    I think I like the idea of the Santa Cruz Nickel frame - single pivot with a modified shock rate linkage.



    As a 29er, of course.

    Seriously, if something like this couldn't be built in steel under 6lbs (and even less in Ti) then there's something wrong.

    The only thing I don't like about the design - for customisation - is the fact that it would be much better if the top and downtube were largely free from pivot points.
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  17. #17
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    sorry to interrupt, especially as a lurker and non-framebuilder, but there used to be another option, but since Maverick has gone out of business, i'm not sure of anything similar.

    Seven made a beautiful frame around the jack-shaft style suspension system. this example happens to be my dad's

    ok, back to lurking. keep up the good work, all!
    Attached Images Attached Images

  18. #18
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    Small Canadian builder Xprezo is doing a mixed material frame. Front triangle is aluminium and the rear out of steel.

    I have a couple rides on my new Super-D and really really like it.

    CYCLES XPREZO - SUPER-D - FR



    The frame is 2633g with shock. Pretty good weight for a 145mm travel bike.

  19. #19
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    Steel for the rear triangle and they still couldn't get the chain stays under 17"?

    Good weight though.
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  20. #20
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    Quote Originally Posted by Thylacine View Post
    Steel for the rear triangle and they still couldn't get the chain stays under 17"?
    Regardless to what you read on the internet life does not revolve around chainstays shorter than 17".

    They likely could have gone shorter but 17" is pretty spot on for a fs of this nature.

  21. #21
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    My last bike had 17.75" chainstays, but thanks for wording me up on what the Internet says.
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    How about a "plug and play" carbon rear end? They have special carbon chain and seat stays for road bikes, how about a standard rear end where the main variable are the pivot points and amount of travel?
    PVD, your next project? How about a "tele-lever" soft tail?
    Hope your are feeling better...

  23. #23
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    I did a lot of the detail work on the nukeproof scalp dh bike , this is a single pivot with a linkage driven shock

    What I tried to do was to make a single part with bb swinging arm pivot and linkage bearing all machined together
    So all three major points are in the same plane and at distances , infact in production the linkage pivot was welded to the top of the I beam seat tube part but all machining was done together

    Certainly an investment cast bb with bb and swinging arm pivot on would be a good start

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    Sorry trying to find a pic of the scalp to link to but have failed

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  25. #25
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    What ever happened to this. Split Pivot Suspension - Ride for fun.

  26. #26
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    It's on Devincis right now.

  27. #27
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    Quote Originally Posted by ade ward View Post
    Certainly an investment cast bb with bb and swinging arm pivot on would be a good start
    I think CNCing is perceived as more modern, so I'd probably steer away from IC.



    Quote Originally Posted by Yogii
    How about a "plug and play" carbon rear end? They have special carbon chain and seat stays for road bikes, how about a standard rear end where the main variable are the pivot points and amount of travel?
    Yeah the key would definitely be adjustability. I was thinking just now that the collectivisation should involve the parts that are cheaper to make in volume, so in terms of something like the Nickel design, an independent entity could say make the links and pivots, and the main link 'tower' 'Y' so that that custom builder could add in whatever style of chain and seatstays and dropouts they liked.

    I think doing something in carbon would be too 'mainstream' looking and lack real world customising.
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  28. #28
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    Warwick,
    Do you have the time to put in about $24,000 of your own time and at least $10,000 for prototype CNC parts plus another $1200+ for someone to fabricate each proto?
    If you don't just build a straight up Santa Cruz Superlite style bike.
    Shock technology is so freaking good right now that adding lots of complexity only makes sense on a large production scale if you have a leverageable patent.

    That's my 2cents(says the guy that can't afford to proto his FS frames that use a leverageable patent).

  29. #29
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    Quote Originally Posted by Thylacine View Post
    I kinda think that there is an emerging untapped market for performance full-suspension bikes - we're just not exploiting it.

    There's a couple of points here.

    Firstly, when I looked into licencing a rear end (ha) a couple of years ago as a point of difference to the Ventanas, the cost of the chainstay/seatstay parts were USD275, mill finish. Rockers and all pivots added USD114, making a raw cost of USD389. I can't remember how much OE shocks are, but I think about USD80? I guess everyone is getting the picture.

    Secondly, I'm sure everyone recalls the "Aluminium is great because it's cheap to machine and easy to manipulate blah blah blah" conversation as it pertains to full suspension frames, but do you realise 'modern' Aluminium 29er trailbike frames weigh on average 6.5lbs (3kgs)?!

    Dunno about you, but a heavy, large size 29er hardtail in STEEL weighs circa 2kg, so add 200g for a shock, and that leaves you with 800g worth of links and reinforcement? Seriously?

    Steel is real fellas, come oooooooon!

    the Product of COTIC cycles : droplink ROCKET a steel full susser with 150 mm of travel

  30. #30
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    Quote Originally Posted by SuspectDevice View Post
    Warwick,
    Do you have the time to put in about $24,000 of your own time and at least $10,000 for prototype CNC parts plus another $1200+ for someone to fabricate each proto?
    If you don't just build a straight up Santa Cruz Superlite style bike.
    Shock technology is so freaking good right now that adding lots of complexity only makes sense on a large production scale if you have a leverageable patent.

    That's my 2cents(says the guy that can't afford to proto his FS frames that use a leverageable patent).
    No, but I'm sure five of us could throw 5k each at the problem and have a fully customisable design covering both wheel sizes, 100-140mm of travel, and still be able to add our individual flare to the final product.

    I know how much things cost.

    Mister Kavik, you listening?

    I need to make some emails.....
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  31. #31
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    Quote Originally Posted by compositepro View Post
    the Product of COTIC cycles : droplink ROCKET a steel full susser with 150 mm of travel

    Gee, the Cotic is a very 'English' design, isn't it. I'd look like a dog humping a football riding something with a 24" top tube and an 80mm stem, with a 66.5º head angle.
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  32. #32
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    Quote Originally Posted by Thylacine View Post
    Gee, the Cotic is a very 'English' design, isn't it. I'd look like a dog humping a football riding something with a 24" top tube and an 80mm stem, with a 66.5º head angle.
    Not to the Antipodean tastes then?

    Size it long, size it low, make the wheel be somewhere in the next county, that's how us poms like our bikes. You should build yourself one and try it, I specced my hardtail not far from that geo (bit longer in the middle) and it's brilliant..

    ... but then I am very English.

  33. #33
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    I mean, the thing isn't even a 29er ferchrisake!
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  34. #34
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    Quote Originally Posted by Thylacine View Post
    Mister Kavik, you listening?
    I'm all in.

    But, where are the customers? Would "the collective" truly get behind a catalog of open source suspension parts?

    I genuinely believe in the concept and have the resources, sans capital, to execute it. But, unless there's support from the community, it would die on the vine.

    Let's figure this one out.

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    Well of course the extent of my market research begins and ends with 'what would I like?"



    Seriously though, these are my thoughts on the matter.

    I don't really like hardtails. I see less and less of them during rides and at the races. Doesn't mean they don't have their place, but they do have serious limitations for a large segment of the XC/Enduro market that I'm mostly interested in.
    Customers, riders, are in an increasing time crunch, and IMHO to ride a hardtail as quick as a full suspension bike, you have to be fitter and spend more time on the bike. There's a reason bloody 5" travel fred bikes are so popular - people want to get on the trails, have fun, and recover quicker to go back to their day jobs. And dare I say it - who are your customers? Sure, there's a bunch of hardcore guys, but I'd bet most of you sell 5k+ bikes that are only ridden on the weekends by upper middle class guys with a modicum of taste (of course!)

    What's stopping most of your customers NOT buying full-suspension bikes, if given the option?

    From my own personal perspective, I just honestly can't ride hardtails anymore, and the last time I had fun offroad was when we were trialling out some Turners for use for a project just like this one I'm sorta kinda proposing. If you can only ride a couple times a week and the odd weekend, unless you're riding nanna trails, hardtails kill you, that's the bottom line for me. I want to sit down and pedal, not spend 4 hours hovering over a largely ornamental saddle.

    At the enduro races, 4" travel bikes absolutely dominate. After 6/12/24hrs, suspension is an energy saver which can't be denied. Man, I rode a Scandium hardtail at a 12hr and couldnt walk the next day. Luckily.....I work for myself.

    Largely though, I think, the custom frame world is in suspension denial.
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  36. #36
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    W,
    I should have clarified...I am proposing to provide these parts to builders. The task is right up my alley.

    If the DIY system had all the right ingredients, what builders would pony up and actually buy?

    I could supply prefabbed kits, ala Ventana. But I would imagine builders would have some fun building the welded assemblies themselves in 7005, 4130, or Ti. Components would have a bit of interchangeability for travel, heft, and wheel options. Hardware, pivot assemblies, support tooling and fixtures would be available as well.

    This is where I'm headed. Just need buyers...

  37. #37
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    Quote Originally Posted by Thylacine View Post
    ...I don't really like hardtails. I see less and less of them during rides and at the races. Doesn't mean they don't have their place, but they do have serious limitations for a large segment of the XC/Enduro market that I'm mostly interested in.
    Customers, riders, are in an increasing time crunch, and IMHO to ride a hardtail as quick as a full suspension bike, you have to be fitter and spend more time on the bike. There's a reason bloody 5" travel fred bikes are so popular - people want to get on the trails, have fun, and recover quicker to go back to their day jobs. And dare I say it - who are your customers? Sure, there's a bunch of hardcore guys, but I'd bet most of you sell 5k+ bikes that are only ridden on the weekends by upper middle class guys with a modicum of taste (of course!)...
    I know this is off topic, but at my local trails in Missouri, at least 1/2 to 2/3 of the riders are riding rigid...
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  38. #38
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    Hey Guys -

    I have a baby coming (gah! 5 weeks to go!) Our first. I anticipate being totally incompetent at being a dad. So I have zero time to invest in participating in designing (or funding) this project. That said, I've probably built 50 FS bikes, and I like building FS bikes, and I agree with the basic idea that FS bikes are a good thing to be able to provide to customers, especially if you can customize stuff.

    I might buy what you're selling, though. Here's what it would take:
    -Single pivot (quad bearings, keep it stiff). Sorry, anything more complex is going to be a nightmare.
    -Probably seat-tube rocker driven shock. Seat tubes are relatively easy to do weird crap with. As soon as the shock needs to mount to the downtube or toptube (often in addition to the seat tube), things get difficult.
    -Some flexibility with hubs. 142? 135? Something else? I don't know where the industry is going to settle, but a kit that allowed different dropout options would be good.
    -Cheaper than the ($650) Ventana.
    -Lighter than the (~1300g) Ventana.

    Actually, to be honest, I would buy a few just on the general principle of supporting this kind of project almost no matter what. The community has been very good to me in supporting the various stupid ideas I've had built. But if you can do those things, I'd be even more psyched.

    -Walt
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  39. #39
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    I've built 1 FS, recycling a rear swing arm from another (production) bike. I would buy a few kits. absolutely.

  40. #40
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    Quote Originally Posted by jgerhardt View Post
    I know this is off topic, but at my local trails in Missouri, at least 1/2 to 2/3 of the riders are riding rigid...
    Damn, and to think I was in St.Louis in September, too.

    Walt, I'm on the same page as you with this (except I have a 4 year old, and not expecting any more. I hope.) That blue Ventana based bike you did recently has really been a moment for me, realising that steel actually is viable.
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  41. #41
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    IMHO, you guys are going about this wrong. You build custom bikes and it doesn't matter who builds/supplies an out of the box rear suspension, it's not you, so in the end what makes it any different than using a Ventana/Yeti/whatever rear tri? I think a better idea would be to just have a source for the harder to fab bits like various bulletproof pivots/rockers/etc. Then you get to design/build your rear end, choose the tubes you want for stays, make it a single pivot or Rube Goldberg or something in between, but most importantly, really make it your own.
    A man must have enemies and places he is not welcome. In the end we are not only defined by our friends but those against us.

  42. #42
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    Rube Goldberg i thought i havn't heard of his bike designs before, so googled him,

    you have to forgive me I am english and we have our own Heath Robinson who designs stuff like that ,

    i have a designed a bike he would be proud of the Whyte Prst-1

  43. #43
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    I have to admit its probably easier to say

    ere ade make this suspension work !!!! (having had quite a track record of suspension design)

    then engineer what he comes up with

  44. #44
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    What do we reckon is Ventana's volume of rear end kits for custom builders? Couple of hundred, tops?
    No longer member of the bike industry nor society, so don't hassle me.

  45. #45
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    Not many

    I would be shocked if it's triple digits. I could be totally wrong, though. Most builders I talk to *never* do FS stuff. Heck, many of them never do mountain bikes.

    -Walt

    Quote Originally Posted by Thylacine View Post
    What do we reckon is Ventana's volume of rear end kits for custom builders? Couple of hundred, tops?
    Waltworks Custom Bicycles
    Park City, UT USA
    www.waltworks.com
    waltworks.com/blog/
    instagram.com/waltworks/

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    Hey guys keep this thread going

    Hey guys, by all means I am no pro frame-builder.
    Just my hobby but I would have to say building a full squish bike is on my list of things to do.

    I think you are on the right track to say single pivot, but will have to include an extra faux point to increase stiffness.
    I also think the whole rear end to be sold a suss kit will not fit the range of uses people have in mind.
    Maybe just some dropouts with pivot/bearing points CNCed into them, and seat tubes with pivot/bearing mounting points, on different thickness of tubes and the length of the little pivot section be varied for suss travel.
    That way people can weld in the tubing they think will fit the requirement, and vary the lengths to match chainstay and BB drop, travel length, and so on.

    Here is a sketch of a design I think will work and keep things simple, give progressive travel and pedal efficiency.

    Take it for what you paid for it.
    Attached Thumbnails Attached Thumbnails 29er Suspension design - XC/Enduro-suss.png  


  47. #47
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    I got a response from Ventana - They reckon 100 during a lean year, 200 for a good year.

    Yes I agree - as little homogenization as possible is key.

    Made some more inroads this week, I'll post more later.
    No longer member of the bike industry nor society, so don't hassle me.

  48. #48
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    Quote Originally Posted by Crispy01 View Post
    Hey guys, by all means I am no pro frame-builder.
    Just my hobby but I would have to say building a full squish bike is on my list of things to do.

    I think you are on the right track to say single pivot, but will have to include an extra faux point to increase stiffness.
    I also think the whole rear end to be sold a suss kit will not fit the range of uses people have in mind.
    Maybe just some dropouts with pivot/bearing points CNCed into them, and seat tubes with pivot/bearing mounting points, on different thickness of tubes and the length of the little pivot section be varied for suss travel.
    That way people can weld in the tubing they think will fit the requirement, and vary the lengths to match chainstay and BB drop, travel length, and so on.

    Here is a sketch of a design I think will work and keep things simple, give progressive travel and pedal efficiency.

    Take it for what you paid for it.

    Crispy,

    Thanks for the input, but IMHO it won't be that easy. We've done 4-5 FS bikes with the Ventana rear end. We've got a mock up in a CAD file that allows us to move stuff around and see what can change before we start to cut tubes. The whole CAD mock up was done with our measurements of the actual Ventana items. However, if we ended up missing a measurement by accident, then the whole rear assembly would "explode" in the CAD program when running through its range of motion. I.e. each individual piece in the faux bar setup does have to work in concert with each other. Thats part of why the Ventana kit is so appealing. The basic heavy lifting has been done already. You just get to play with it a bit upon fabrication.

    We are following this thread, and I think the whole concept is great. We'd love to do more FS bikes. But even with a little bit of experience, along with a desire to do more, we still only avg about 3 per year.

    Later,
    CJB



  49. #49
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    Frankly, I don't think the Ventana kit is going to shift people's perceptions or grow the custom FS market. Again, I think it boils down to the fact that HALF the frame has Ventana on it - you can't adequately stamp your own DNA on the finished article.

    I also think that faux bar bikes' time has come and gone so you're solely relying on customers wanting to buy an FS rig from you because they strongly identify with your brand or have some fit issues - that's not enough reasons to create a new market. I think the custom bike industry should be driving more change than it currently is - there's a real danger it will be seen in a few years time as the place you go to only to get your 'retro' bike, or stratospherically priced Titanium road bike.
    No longer member of the bike industry nor society, so don't hassle me.

  50. #50
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    I disagree

    Model some real 4-bar or Horst or VPP type rear ends and see how much "customizing" you can do with the pivot locations and geometry before things go to hell... *then* tell us about how single pivots/faux bar are dead. For small-run production builders, it's a different story, but if you want to do really "custom" (ie, whatever bb height, chainstay length, etc) you want to keep it single pivot.

    There are lots of hot new bikes from the big boys coming out all the time that are one or another variety of single pivot - because they're light, stiff, and reliable. And a good shock, IMO, negates 90% of the advantages of more complex designs.

    I agree that building FS bikes is important (I build probably 5-10 a year), but honestly you are trying to run before you walk here IMO. The Ventana kit can be improved on, yes, mostly just by modernizing (142 or 135 x10, post mount, etc) and freeing up chain/seat stay customization options. A dropout with built-in disc mount and pivot mount, chainstay and seatstay yoke/bearing fittings, and some type of rocker or other linkage to drive the shock is about all you really would want to do.

    Trying to get fancier than that is just going to end in tears, I think.

    -Walt

    Quote Originally Posted by Thylacine View Post
    Frankly, I don't think the Ventana kit is going to shift people's perceptions or grow the custom FS market. Again, I think it boils down to the fact that HALF the frame has Ventana on it - you can't adequately stamp your own DNA on the finished article.

    I also think that faux bar bikes' time has come and gone so you're solely relying on customers wanting to buy an FS rig from you because they strongly identify with your brand or have some fit issues - that's not enough reasons to create a new market. I think the custom bike industry should be driving more change than it currently is - there's a real danger it will be seen in a few years time as the place you go to only to get your 'retro' bike, or stratospherically priced Titanium road bike.
    Waltworks Custom Bicycles
    Park City, UT USA
    www.waltworks.com
    waltworks.com/blog/
    instagram.com/waltworks/

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