dminor 

Doesn't everyone huck off rocks?

cyclops

Dumb, dumb, dumb. Why fix something that not broken, does it really add anything to MTB design?

C Law

I think the idea is to destroy any preconceived notions about what a rigid bike can handle.

ed 

Interesting point.

TimJ

I think the geometry is really interesting. The seat is waaaay back over the tire. There might be something to it in that regard.

bikinfool

I've chatted with a coupla guys on theirs on the local singletrack, and they rave about the bike. Outta my price range these days, but if I had the coin and the patience to be on the waiting list, I'd probably do it.

As to the riding in/around/off rocks, believe that photo on the website is him, so it'd be natural for the bikes be suited for it. If you need more traditional suspension guess this might not be an option for ya.

ed 

Any of those you chatted with dudes you know that would let you do an impartial review or are they just peeps you ran into?

bikinfool

No, just guys I met at intersections on the trails and chatted; last guy was someone I thought I'd chatted with before, but ended up just kinda looking like him and had a much different bike setup, had an front endomorph wheel setup and was geared, whereas the other guy I was thinking about was ss and no big wheel/tire. Never even thought to ask to try the bike, as don't like just jumping on someone's bike with no time to tweak setup (and then guys with that much money into their bikes probably aren't going to be too keen on that idea even with one of my fairly nice bikes to hold as collateral). Wonder if Jones has any kind of demo program?

ed 

From Dirt Rag:

DR: What's up with your four-legged rigid titanium fork?

JJ: It's just a light and strong fork. If you went to any mechanical engineer and asked for the lightest, strongest design, nobody would give you two fork legs headed straight down. That's silly. Basically it is a truss fork design from the 1930s, when bikes started to look like motorcycles. My fork is triangulated. A normal fork bends just under the lower headset-where all the energy is focused. With a triangulated design, the force is distributed throughout the whole structure. It's not just two legs relying on their own brute strength.

I'm doing stuff like five-foot drops with no problems. The fork weighs 1.6 pounds, has enormous mud clearance and very precise steering. The upper and lower headset are both upper headsets and there is no crown race. I also have a 2.4-pound, one-piece system that includes fork, stem, steerer tube and handlebar. Things work better when they are designed to work together.

ed 

DR: Your 3-D Spaceframe is striking. What is the logic behind the multiple top tubes?

JJ: Thank you. People do comment about the aesthetic, but it wasn't designed for looks. I tried to push the laterally stiff, vertically compliant envelope as far as I could. The shock from the rear wheel is not driven into the seat tube and up the seat post on this design, but dissipated into the curved seat stays. The rear end is closer to a parallelogram than a perfect triangle. Also, the frame is horizontally triangulated and has four tubes connected to the head tube to improve lateral stiffness and strength. You can feel the difference. The seatstays and chainstays are ovalized in a horizontal direction, again to give more vertical compliance with less lateral flex. Also on my singlespeed version, I have 15.1" chainstays. Normally they're about 17 inches. Having the rear wheel tucked under you like that works great for climbing out of the saddle.

ed 

DR: What do you charge?

JJ: Anywhere from $1,900 to $3,000 for a full custom frame and from $3,500 to $7,000 for a complete custom bike. I don't plan on making much more than 50 bikes a year. The handlebars are $159 to $199. For more information on Jeff Jones Custom Bicycles, visit www.jonesbikes.com.

Glynis27

I think they look like fun. Would totally ride one if I could. I love the looks of a stubby, unconventional bike. Maybe some day when I have lots and lots of money.

Lets_roll

Some people might make em a nice fixie... ROLL YO JEaNZ UP, AND RIDE.

cyclops

As it happens I am a mechanical engineer and I disagree with Jeff Jones. He is correct insofar as a triangulated structure will spread the load from a point throughout the structure. However that is true of any structure subject to a load, the load will be distributed through the structure. Depending on the particular design the load will be spread entirely throughout or concentrated in several key members.A simple tube fork also spreads its load throughout its structure, its just that there is less of it to spread the load through. As for the assumption that "If you went to any mechanical engineer and asked for the lightest, strongest design, nobody would give you two fork legs headed straight down. That's silly" Then I must be very silly indeed as that is exactly what I would design. Two tubes headed straight down. Two large diameter thin wall tubes, giving high strength and maximum rigidity. Of course a fork like that would also be cheap to manufacture and therefore cheap to buy, could be on to something there.

Lets talk about good engineering practise for a minute, generally if you have the choice you will load a member in tension in preference to loading a member in compression, this is what I was taught, I'm sure there are others who disagree, bring it on. By putting the triangulation ahead of the main forkleg Jones is placing them in compression, this means they act as springs and try to transfer that load any way they can, In compression they will bend and bow unless they are prevented from doing so, more weight and uneccessary metal is required to prevent this. To cap it off they are curved and thats just begging the forces to bend them some more. If you were unsure enough of your design to require a triangulation on your conventional ridgid fork, that all it is folks, then a good engineer would do in such a way that the triangulation was in tension. How? well you could put it behind the fork leg for staters, two straight lines going from the bottom of the fork to a point behind the headset or just below it and thence straight to the upper headstem. Possible disadvantages? restricted steering lock, maybe, you could do it and minimise restriction, I think, without prototyping, you could do it with minimal difference to steering lock. By putting the additional members in tension they will still act as springs, as all structures do, but they will not require addditional metal to restrain their bending and bowing because there wont be any. Try this at home, compress a long spring, do not under pain of imminent structural failure allow the spring to bend or bow in any direction, fun eh! now take the same spring and stretch it out do not let the spring bend or bow under pain of blah, blah, blah. Wasn't that easier?

Personally I think ths is a classic example of answering a question no-one has asked, the history of engineering is littered with their bones, flying cars, floating cars, the solar powered torch. One of the few advantages of a litiginous society is that it acts as a filter for the worst ideas in engineering, any thing sufficiently stupid as to kill people wont make it past the concept stage as insurance will kill it, this still leaves plenty of room for the merely redundant to operate in however. That is where the Jones lays in my opinion, redundant. designed to answer questions no-one asked and destined to bought by a few with more dollars than cents/sense then quietly dissapear with its manufacturer bemoaning the lack of support for innovative design and the tyranny of the majors crushing the independents. Like say IF or Soul or Litespeed or .....

ed 

Could somebody summarize the previous post so I don't have to read it?

cyclops

Poor design and overpriced. sorry I had to use big words.

santiago

Explain it to me like I'm 5 years old.

ed 

Poopee, peepee. It bad fo U.

ed 

Do you think his purpose behind the non-trad fork design was to increase strength, decrease weight, and increase vertical compliance and lateral rigidity so it's not so harsh yet still snappy when you lean into it? As he said...it's a 1.6lb fork and they're doing some pretty "non-XC" terrain with it.

Or it could still be a load of crap.




I wonder if Jeff thinks that his idea of "laterally rigid / vertically compliant" from the frame as he said: "but dissipated into the curved seat stays" also applies to the fork necessitating some curved tubes. Maybe/maybe not.




I somewhat disagree. I think there are alot of people out there who buy/build rigid SS bikes that are priced in an absurd way b/c they are looking for something different. (some may be looking for a reason to raise their noses...who knows) They love how simple/elegant a SS rigid bike is and how they feel connected to the trail...yet they'd love to have just enough compliance to take about 1/2" of chatter out of the trail or take the harshness of the bumps. I can see why Jeff says that he wants to create a bike that is more of an extension of the person versus a bike that you feel like you're sitting on top of. I personally don't buy into it nor do I feel that way upon my own ride, but I can hypothetically see a picture of a guy with plenty of money and ample time on his hands to ride many hours per day. He doesn't have many bikes in the stable. He just wants to have 1 bike and climb on that 1 bike that feels perfect to him. If you spend 4-5hrs a day riding the same bike...very small differences can be noticeable. Adversely...like myself...I don't get to ride every day, so you could put me on an OnOne Inbred 29'er, Redline Monocog 29'er, and a Jones Spaceframe 29'er, and I may or may not notice much difference. But if I rode a Monocog 29er 4hrs a day and all the sudden hopped on a Jones and noticed an extra 1/2" of vertical compliance...then there's an answer to a question.

As far as being connected to the trail though...I think it's a load of Hogwash! I like to be disconnected from the trail. When I see a rough section coming up...I hit the first bump in a way to try to propel me across the rest of the section. I don't want to bounce my way across it...I want to fly over it and have my suspension suck up what I can't clear.

Maybe one day...I'll calm down a bit and want a nice compliant XC sled...we'll see. I know that if I lived about 25mi East of my current home...I'd own a 20-25lb rigid 29'er for a couple of local swoopy trails that are fun to just motor through but have basically no bumpy sections...just swoopy speed.

S.D.XC

same here!!

cyclops

I'm just finishing assembling all the parts for my own SS build, it will have front suspension though. If I wanted a little give in my rigid front end though I'd look at a tapered steel fork, If I had bulk dosh I'd look at a tapered ti fork but there's no way I'd look at a Jones.

-_RebelRidin'_-

Would I ride it, No.

Would I take it if someone gave it to me, yes. Because it has good components on it. I'd strip them off, and use them, and then sell the frame.

Zephyr11

Eh, if someone gave it to me for free I'd ride it, see what I thought of it, and if it was amazing, I'd keep it. Anything short of amazing and I'd sell it and pimp out my other bikes with the profits. I'd never buy it on my own though, even if I was loaded. Wonder how it compares to this other ridiculously expensive and ridiculously ugly bike.

joetronic

Sometimes it doesn't matter why its there, or if its a different answer to the "question no one asked," Some people just like to be different. If you like it, and can afford it, more power to ya. Not everyone needs to know why something looks of feels certain way, just that they like it.

Kinda like the whole SS thing. Everyone says they ride, or started to ride SS to be "more connected" blah blah, but if you ask anyone how they really felt, they wanted to be different than their buddies, but still fit into a trend at the same time. Like me, I ride SS. To be compleatly honest I started to be cool, but different than the guys I ride with, then got hooked. Now most of us ride SS, so to be a little different, I went 3spd(see my 3spd thread.) The jones bike fits the same bill, as well as many many others out there. Its for someone who wants to fit the trend of SS boutique style bikes, while also being a little different at the same time. For example, look at black sheep cycles. All for the sake of fashion, just a little different, but fits what's in trend to a T, while owning a little bit of originality. EXAMPLE

None the less, I'd ride it. Maybe not on the trails, but as a townie/bar-hop yes.

1955

Good read, thanks!