Road Unicycle Set-Up and T7 Handle Modification

[GizmoDuck]

@scotthue

Yes but unlike a mountain bike, the “suspension” does nothing for the rest of your body and puts more stress on the top tube.

Possibly, but then I don’t think we have ridden enough V-frame designs to know for sure. I’m guessing that when people spend more time with a more bicycle like position, you will find that having something to dampen road shock on your hands might be useful. But that’s a bit beyond my experience on the setup still.

[uniaddict]

@kerosian

Well, here’s my new design with some quick sketchup photos attatched. The problem I am trying to solve is that I want to acheive the comfort and stiffness of a V frame but with the weight of a typical flat crown shaped frame. I acheive this by replacing the second tubes with 2 tensioned stainless steel cables anchored where the forward frame legs should be. I have a bar running to the handlebar tube and back to the seat tube to triangulate the frame to achieve this shape. While it isn’t in the pictures, I plan on attaching a mechanism to remove the top tube, enabling the entire forward piece to be removed and enabling the frame to be ridden in V mode and as a normal frame. Cable tension is adjusted at the bearing clamp anchor with a simple nut and bolt tensioning arrangement. Comments, questions, complaints, I’d be glad to hear them.

I think the design would be a lot better if you switched the curved top piece for the cables and vice versa. On top of that, if you made the cables cross over like an X rather than being parallel then it would have more lateral stiffness IMHO.

[kerosian]

@naturequack

Kerosian,
Excellent plans. Very creative. Now you’ve got the whole R & D team working out the kinks before you’ve spent a dime on metal. I agree with pretty much all the previous comments. One more that I’d like to add is that I think it would be better to have the seat and handle bar-mounting tubes to be following the angle of the V frame. You have both tubes pointing vertical and parallel. (Calling these tubes vertical assumes that weight is being distributed equally between the seat and the handlebar. That weight distribution would result in each of the arms of the “V” having the same angle with respect to gravity. In my experience my weight is not even close to being distributed equally. I would guess that I might put 10% of my weight on the bars. Much of the time I have less. This unequal weight distribution results in the rear arm of the “V” being much closer to vertical than the front arm of the “V”)
There are two reasons that I don’t think this parallel positioning of the tubes is optimal.
The seat tube: Imagine sitting on the unicycle when you are not holding on to the handlebars. You are sitting straight up just like on a regular unicycle. The rear arm of the V is nearly vertical. Instead of a nice straight line of force being transmitted from the seat down through the seat post and into the frame, you’ve got an angle in the line. This is inherently weaker than a straight line. I’m sure it could be made strong enough but more strength requires more weight in materials. Keeping it simple is a good thing.
The handlebar tube. By having it parallel to the seat tube you diminish one of the goals of the V frame, that of extending the handlebars farther out in front. If you were to keep the handlebar tube in line with the front arm of the V you could gain an inch or so of forward reach, depending on the length of the handlebar tube. An inch is a long way in the handlebar world. Maybe I’m getting nit picky and I’m being too much of a weight weenie but bear with me. You could probably save a few grams by closing the angle of the V by a couple degrees and keeping the handlebar tube in line with the front arm of the V and still maintain the same reach. Or you could maintain the same angle of the V and just gain another inch of reach.

Keep up the good work. You’ve got us all thinking about new designs again.

Geoff

I am attaching the handlebar and seattube bar at the same angle as whatever the framebars are, but it was difficult to get the angle’s correct on google sketchup without some large amount of time. This is in no way a finished design, just a stir in the pot of ideas.

[IUni]

That was tough triying to catch up on a whole thread. The topic of on the fly adjustments…would a handle length adjustment vs a seat position adjustment be possible? I’m thinking something like a TravelPro suitcase handle, with a grip release.

[IUni]

@kerosian

The bar bridging the gap would also have a force upward because of the way it is bent, sort of like a spring. I may also put an elastomer in the center to give a suspension feeling to it, sort of like having a suspension front fork, in a way working out like slingshot bike frames (photo attached).

Could you cantilever that with opposing cables?

[kerosian]

@IUni

Could you cantilever that with opposing cables?

I assume I could. I would have to see exactly what you mean.

[IUni]

@kerosian

I assume I could. I would have to see exactly what you mean.

Think of a tower construction crane. i’m just throwing out ideas, and am impressed with your thoughts to this point.

[kerosian]

ok, I see what you mean. That could stiffen the toptube without adding too much complexity.

[unijuul]

I have now tried the “seat-back” option and can give a review. I have just start the cycle season here in Norway because of very much snow this winter. First I tried many different cycle saddles to find something god to sit on for hours.

For me the “seat-back” option was not good at all.

• I feel that I have more power sitting uphill

• Cranking uphill is more difficult with narrow seat and “seat-back”
• Much more difficult for me to spin at high cadence
• Going downhill is really difficult

As a result of the “seat-back” experiment I now even sit more in front on the unicycle than I did before. I have watched the “The Flying Scotsman” movie. You can see in the movie that Graame Obree had to cut the front part of the seat to get it legal to the UCI laws. If it was no laws Graame Obree had sit even further in front of the bicycle. So it was interesting to try this set-up, but I would sit in front of the unicycle in the future.

-“The Flying Norwegian” - in a UPD…

[Klaas_Bil]

Sitting more to the front of the unicycle doesn’t change your fore-aft position with respect to the cranks, because the unicycle will tilt back if you move the seat to the front. The only effect is that the handlebars are closer, which would be more like Obree has them to, but which doesn’t look comfortable to me.

An even stranger thing on that Graeme Obree picture is the limited extension of his legs. They seem to be quite bent all the time. Aerodynamically that may be an advantage, but for effective power delivery it doesn’t look good to me.

But maybe I’m missing something…

[caudy]

I agree. How can he possibly get lots of power with such bent legs. Surely it make it more difficult. Maybe it’s just the way he’s photographed.

[unijuul]

@Klaas Bil

Sitting more to the front of the unicycle doesn’t change your fore-aft position with respect to the cranks, because the unicycle will tilt back if you move the seat to the front.

Try it! You will notice the difference.

[maestro8]

@IUni

Think of a tower construction crane.

That’s a great idea, and with a little more work, could lead to an adjustable V-frame.

Here’s a picture of a cantilever jib crane… think of the wall as the uni frame and the boom as the handlebar support. If the boom’s support was a pivot, and one could adjust the length of the cable, then the boom’s angle would be easily adjustable.

I dunno if the adjustable V would have a practical purpose… it certainly would help in the fitting process, but would one want to adjust the V during a ride?

Guess we’ll have to make one and find out!

[yUNIkoner]

@unijuul

I have now tried the “seat-back” option and can give a review. I have just start the cycle season here in Norway because of very much snow this winter. First I tried many different cycle saddles to find something god to sit on for hours.

For me the “seat-back” option was not good at all.

• I feel that I have more power sitting uphill

• Cranking uphill is more difficult with narrow seat and “seat-back”
• Much more difficult for me to spin at high cadence
• Going downhill is really difficult

As a result of the “seat-back” experiment I now even sit more in front on the unicycle than I did before. I have watched the “The Flying Scotsman” movie. You can see in the movie that Graame Obree had to cut the front part of the seat to get it legal to the UCI laws. If it was no laws Graame Obree had sit even further in front of the bicycle. So it was interesting to try this set-up, but I would sit in front of the unicycle in the future.

-“The Flying Norwegian” - in a UPD…

I like the shifters on your T7!

[monocyclism]

Came across a photo of this arrangement and thought it would make a relevant contribution to this thread. Probably computer generated. Looks like 'glass or carbon frame. Like the single fork leg. Individual adjustments don’t look very flexible. Fairly unrealistic proposition then?

[eenwieler-sander]

update: v-frame

an update on the progres of my v-frame:

its going to be finishd next week if nothings goes wrong now

had some trouble with the machine breaking down 2 weeks ago
that has been fixed now so the last peaces of my frame will be made next week

i have already see the frame legs finishd did not bring my camera with me then so dont have a picture of it

for the people that dont know what frame i"m talking about this one:

[jogglingflurpy]

Comments needed in custom built handlebar for 36’’

I’d love some feedback from RTL or long distance riders.
I’ve built a handlebar for my Qu-Ax standard, and now for my coker.
Pics attached below.

The Qu-Ax (silver) I welded a pole to a clamp, attached a brake to it, fitted a single bicycle handlegrip, and wrapped it with racing bike handlegrips.
It worked very fine, but did not gave the option of resting both hands. I had to put one hand on the other, which was not too comfy.
Furthers I’ve done on that setup is about 60km’s.

I upgraded to a KH, and tried something different.
The handlebar is attached with a clamp to the frame directly.
The pole of the handlebar is the same thickness of the verticle pole on a bicycle where you fit the handlebars on.

Bike shop gave me an old racing bike handlebar, so I’ve attached it with the tighteding screw into the pole.

Advantage is I can lengthen and shorten it. (Mechanism of raising handlebars on bike)
I can also turn it around.
At this stage, it is very long, so I will most likely shorten the pole a bit.

Then I fitted 2 handlebars, also stardard MTB accessory to it.

Any comments or ideas on the length and angle of the handles welcomed.

I see the T7 bends upwards, while Sachawaman had a photo up on the forum with his bending downwards.
Any experienced rider’s comments on placement of handles relative to seat, is welcome.

[scotthue]

Look’s great! I’mt thinking about making a handlebar like this once I get the money for a KH 36 frame. What is the ID of the clamp on the frame (the OD of the large part of the seat tube) and what OD/ID did you use for tubing (and is it chromoly)?

[nathan]

That looks nice. Somewhat similar to the handle I’m using these days. This worked out really well on the India tour. Yours is a little more extended I guess, and maybe a touch higher. It’s hard to know what’s best, but I do know my setup works nicely.

—Nathan

[jogglingflurpy]

Putting the handlebar on the frame has 2 purposes:

1. It leaves me more room for moving the seat up and down. My previous one was restricting me.
2. I was stuck without a handlebar, and kindof got used to the brake attached to the seat. When downhilling, I also tend to sit up straigther, so I think the brake on the seat is a better idea than having it on the handlebar. I needed sufficient space for the brake on the seat, without the handlebar interfering.

I also thought it may be more solid. The new KH handlebar on this thread appears to be too far from the frame. (you turn the seat, which turns the seatpost, which turns the frame.)

Scotthue, Not quite sure what you are asking. I can’t weld, so I asked a friend to make me a clamp and weld a pole to it. I think it is stainless steel.

After reading the forum again, I think it will be a good idea to figure out a way to move the seat back an inch or 2 to compensate for the weight of the handlebar, and the weight I’ll be putting on it.