Prototype 29er

Unicycles and Equipment
1

I’ve been working on another prototype uni - this time a 29er. As some of you might know, I’ve built several machined aluminum 24" MUni’s but this is my first road cycle. The new frame is very much like the others I’ve built except you could say this one is “stupid light” in it’s minimalist design. In other words, I’ve tried to make it as light as I could but I might have gone too far!

There’s a couple changes based on the testing that’s been done on the MUni frames. This one still uses the “pinch bolt” type bearing holders but I’ve added a small lip around the outside to help retain the bearings. Oddly enough, when the bearings moved in the earlier frames the bearings always moved out so I hope the lip on the outside of the new frame will keep that from happening.

Another change is in the way the seat tube and crown go together. One of the MUni frames failed there - most likely because I assembled it without Loctite. So I’ve added a small step in the seat tube to keep it from slipping down in the crown as well as adding a spring pin throught the whole works to keep things from twisting. Like the earlier frames, the seat tube is a press fit with the crown and assembled with Loctite.

I’ve put some photos in the gallery. They aren’t very good so tomorrow in the light of day I’ll take some better ones and replace them. They are located here:

http://www.unicyclist.com/gallery/29er_prototype

I haven’t ridden it yet but am planning to tomorrow. Should be an interesting comparison to Harper’s uni.5 that I will also ride tomorrow.

Steve Howard

2

Wow! That looks great (even if it isn’t red).

john_childs

3

Steve-

You do such nice work. This is the kind of frame I’m looking for to make the final uni.5. This one looks like bare aluminum. I think it would be cool in anodized blue. If it’s a road uni, I doubt that the bearing clamps will drift. They only moved on the MUni when it was thrashed about.

By the way, I took the MUni to the Carkeek Park trails again with Buster the Disguster this morning. I did my standard lots of falling off and the bearings didn’t move at all this time. Perhaps the tension is just right in the frame now, who knows. The left Shimano crank is still misbehaving somewhat. Did you have a batch of those that worked before? How are the left cranks on the other MUni’s holding up?

4

Re: Prototype 29er

“showard” <showard.6busa@timelimit.unicyclist.com> wrote in message
news:showard.6busa@timelimit.unicyclist.com…
>
> I’ve tried to make it as light as I could but I might have gone too far!
>

Your frame looks great!

IMHO going too light initially is the right way to go. Just put a cheap
paint job on it that is poorly bonded and brittle. The paint will crack
first where the most flex exists. The beauty of your uni frame is that it
is modular; you can rebuild just that component.

Doug

5

I dont like you! Not at all! Why?, you ask? Its simple. You are making such cool unis, and not making them available to all us common folk without fancy shmancy machining stuff. If they work, sell them. You are just a uni hog. All for you, and none for us.

You know I’m just busting your balls, I really love your designs, but please think about making them available to us.
-David Kaplan

6

RE: Prototype 29er

Your new 29" looks very nice.

> I’ve built except you could say this one is “stupid light” in it’s
> minimalist design. In other words, I’ve tried to make it as
> light as I could but I might have gone too far!

For a road riding machine, you mainly want it to be durable. A certain
amount of flex in the frame, as long as it doesn’t fatigue the aluminum,
would probably add to rider comfort.

But for a track racing machine, you will want a frame with no discernable
twist at all. You want all energy to go straight into the wheel. Otherwise,
if strictly for racing, I suppose I’d want it to be as narrow as possible,
for a reduced Q-factor.

> bearings. Oddly enough, when the bearings moved in the earlier frames
> the bearings always moved out so I hope the lip on the
> outside of the new frame will keep that from happening.

Note: the bearings on my MUni still have not moved. This is after pounding
down about 4900’ in 18 miles of the Downieville Downhill (720’ of climbing
and 4101’ altitude loss, equaling nearly 4900’). The seat tube does not
appear to have moved either.

> without Loctite. So I’ve added a small step in the seat tube
> to keep it
> from slipping down in the crown as well as adding a spring
> pin throught
> the whole works to keep things from twisting.

This sounds like a good improvement. There will be twisting forces all up
and down any unicycle frame, so pieces that fit together in round sleeves
should have something to prevent them wanting to turn.

Remember, all, this MUni I am testing will be up for auction at UNICON, as a
fund raiser for the conventions. Start saving up! I will not be auctioning
it here on the Internet because there was no reply to my earlier post about
prices. If you are not going to UNICON and are interested in this cycle,
please let me know. I love it.

My pictures (no new ones yet):

Stay on top,
John Foss, the Uni-Cyclone
jfoss@unicycling.com
www.unicycling.com <http://www.unicycling.com>

“This unicycle is made all from lightweight materials. But it uses a lot of
them.” – Cliff Cordy, describing the very heavy new prototype unicycle he
brought on the Downieville Downhill

7

Re: Prototype 29er

In a message dated 6/18/02 2:11:12 PM Eastern Daylight Time,
john_foss@asinet.com writes:

> reduced Q-factor

My girlfriends name is Kieu My. This is pronounced like the letter Q
followed by “me”. usualy i call her Kieu, and spell it, Q for short. for
this reason, i am forced to laugh, a lot, whenever i see anything talking
about the Q-factor in unicycling. Though reducing it slightly saddens me. I
am going to teach her to ride soon.

I would however, be curious to know what it means?
__
Trevor andersen

8

Re: Prototype 29er

in article mailman.1024553286.22332.rsu@unicycling.org, ChxWitBrix@aol.com
at ChxWitBrix@aol.com wrote on 6/20/02 1:05 AM:

> In a message dated 6/18/02 2:11:12 PM Eastern Daylight Time,
> john_foss@asinet.com writes:
>
>
>> reduced Q-factor
>
> My girlfriends name is Kieu My. This is pronounced like the letter Q
> followed by “me”. usualy i call her Kieu, and spell it, Q for short. for
> this reason, i am forced to laugh, a lot, whenever i see anything talking
> about the Q-factor in unicycling. Though reducing it slightly saddens me. I
> am going to teach her to ride soon.
>
> I would however, be curious to know what it means?
> __
> Trevor andersen
>

It’s the distance between the pedals, measured horizontally. Alternately,
you can think of it as how far apart your feet are while pedaling.

A wider or narrower hub will change the Q. Longer or shorter cranks won’t,
unless they’re also angled out rather than straight.

-Carl