My internet service has been on/off for several days so this is late.
Thanx Greg for the opportunity to ride your creation. The uni tire didn’t have any rub to it until the night before it was shipped. I added more air to really take it up to speed. There was some intermittent rubbing but didn’t seem too bad. I should have dumped more air out before shipping.
The dial indicator gizmo includes a modified over-center toggle clamping device (ViseGrips) connected to a gooseneck stem that is locked into place with an adjustable cam. It was clamped onto a crank at top position since this is the position that backlash would be most noticed. The dial indicator was positioned against the frame in line with the pedal threads. The wheel was held steady and the crank moved forwards and back to read the backlash. Harper has a picture that he cleaned up from my POS picture that I sent to him that shows the gizmo mounted.
Mark Stephens allowed me my first ride on a Coker when he came down to ride the Uni.5. If I understood Mark correctly, this was the tenth tire that he has put on this Coker! The Coker was a great ride. Santa, if you’re reading this, I would like a Coker under the tree this year.
The biggest problem that I had with the Uni.5 is the distance between the pedals. With the new cranks that were sent and getting them further onto the axle, this distance could be closed up considerably. Is there a term for this gap between pedals? The ability to accelerate and brake could possibly be improved by the square of the change in this distance. (Harper is reaching for his calculator).
While riding with Mark, (he on the Uni.5 and I on his Coker) I cut sharply in front of him to avoid some traffic and hoped he could handle necessary sharp turn on the Uni.5. He handled it physically and emotionally just fine. Yes, I did apologize for my actions. So, the Uni.5 responds very well.
I briefly tried Elaine’s 20 inch and had to step off immediately. They said I was leaning way too far forward. The Uni.5 and the Coker must have put me into some kind of warp speed frame of mind even though I rode both rather slow.
My overall opinion of the Uni.5 hub is that it can become part of a very robust uni. My limited knowledge of large wheeled unicycles is that they need a wide flange in order to maintain wheel rigidity. A geared hub will allow narrower flanges and still maintain wheel rigidity. Keep going Greg its evolving greatly. (So does that make unicyclists evolutionists?)
nice pic! someone sould put a chomie on that valve stem or the bullet would look good aswell.on second thought dont,cause i’ll just do that anyway when it comes to me casa.
I affix the vise clamp to the frame neck, with the meter plunger held in line with the the plane of the crank arm, centered on the pedal apature. I then immobalize the frame and bring the crank in contact with the plunger, adjust the crank to one side of the backlash envelope with zero force and minor wheel adjustment, then immobilize the wheel. Finaly, I zero the meter, move the crank, and take a reading.
This methode allows for the crank backlash to be the only moving part- the meter and flexi arm do not move. When done this way, I have confidence that the flexi arm is sufficiently ridged and will not factor into the measurement. The crank contacts the meter plunger, which does not transfer any resistance to the flexi arm and assemblage.
However, vastly (100%+) differnt readings can be had, depending on the pressure applied. I am not sure if this is due to flexing in the crank arm, forcing the gears, or what. With light finger pressure- only enough to move the crank- a typical measurement is around .025". Readings as high as the .05’s can be read with much more force, but are so subjective and erradic as to be useless. To take accurate readings under load, a jig could be afixed to the crate and a set of weights included for consistant readings.
It’s good that you are getting a lower backlash reading than I did.
Harper’s wondering what the hell happened to his yike in Oklahoma. Everyone
should be careful with the high tech visegrips as they will damage surfaces.
This is why I clamped them to the crank, since the cranks are less aesthetic
(read ‘cheaper’) than the frame.
Doug
“rhysling” <rhysling.3f9ia@timelimit.unicyclist.com> wrote in message news:rhysling.3f9ia@timelimit.unicyclist.com…
>
> warning: spoilers ahead
>
> I affix the vise clamp to the frame neck, with the meter plunger held in
> line with the the plane of the crank arm, centered on the pedal apature.
> I then immobalize the frame and bring the crank in contact with the
> plunger, adjust the crank to one side of the backlash envelope with zero
> force and minor wheel adjustment, then immobilize the wheel. Finaly, I
> zero the meter, move the crank, and take a reading.
>
> This methode allows for the crank backlash to be the only moving part-
> the meter and flexi arm do not move. When done this way, I have
> confidence that the flexi arm is sufficiently ridged and will not factor
> into the measurement. The crank contacts the meter plunger, which does
> not transfer any resistance to the flexi arm and assemblage.
>
> However, vastly (100%+) differnt readings can be had, depending on the
> pressure applied. I am not sure if this is due to flexing in the crank
> arm, forcing the gears, or what. With light finger pressure- only
> enough to move the crank- a typical measurement is around .025".
> Readings as high as the .05’s can be read with much more force, but are
> so subjective and erradic as to be useless. To take accurate readings
> under load, a jig could be afixed to the crate and a set of weights
> included for consistant readings.
>
> To recap: my best reading is .025".
>
> Christopher
>
>
> –
> rhysling - Last of the Mississippi Unicyclists
>
> “When they get nano-technology, I want mine to look like little hogs.”
> -Sophie’s Mom
> ------------------------------------------------------------------------
> rhysling’s Profile: http://www.unicyclist.com/profile/411
> View this thread: http://www.unicyclist.com/thread/17612
>
Aluminium Bicycle Euro Cranks run $30- so do Torker frames. Once the hub is freed from this wheel, it will hopefully never see a Torker again. The cranks, on the other hand, may be reborn on another wheel…
BTW: it is going to be REALLY hard to post all these cool tools. What did the Micrometer set you back? I may have to pick one up- for no good reason other than to just have it.
Doesn’t all this stuff just fit in the crate? I’ll make sure everyone gets their toys back at the end. Can you post a photo inline of the dial indicator setup you used? If you’re done, don’t worry about setting it up again just for a photo.
You’re right, the frame is cheap and has a hole drilled in it anyway. I’m hoping to build the final version Uni.5 onto a 700c wheel inside of one of Steve Howard’s gorgeous anodized aluminum frames. The Torker frame is definitely temporary.
The degree of flexibility in the flexi arm is goverened by a dial screw on the end that holds the meter; a cam with a red lever on the vise end toggles the arm from ridged to flexi.
Here is the vise grip being adjusted by a qualified technician:
And here a reading has been taken and the cycle judged to be in top-form:
BTW, it is all my fault that Doug is late with his uni.5 posting. I took some awful digital pictures of the uni, Doug and Mark in bad light with an old camera. Then, I e-mailed them to Doug. Not thinking, because I don’t work with graphics often, I sent all 11 of them attached to the same e-mail. No more than ten seconds later, Cox Communications went down over all of west Norman. That was last Wednesday. Today is the first day I have been able to access virtually anything on the web. Doug also uses a Cox cable modem, so I know that I crashed the whole town. My fault.
