Yah I tried making my own tire and basically it worked.
If anyone wants ideas here was my brainstorming thread.
I am going to make one (32") this spring/summer for sure, I will let you all know how it turns out.
Hi Eric,
Thank you for the link. You talk about a number of different ideas. Would you be willing to summarize your approach to tire building? Did you end up using rubber cement and nylon cloth? Do you have any advice on connecting the bead?
Scott
Would drilling my stealth rim save enough weight to make a noticeable difference, and even be worth doing? And would drilling holes the same size as the kh 29 rim make the rim too weak? It would be used exclusively for distance riding on paved roads.
Edit: The impulse 36er rim, which is drilled, is only 3.2 oz lighter than the stealth (solid) rim. Not sure if that would make a noticeable enough difference, and be worth the time an effort to drill the stealth.
@Terry, Try adding a few ounces of extra weight to your existing rim to see if you can feel the difference. Then you’d know if you’d notice the weight savings from drilling a solid rim without compromising the rim strength for your experiment.
Perhaps a length of wire woven between the spokes would represent a comparable weight…
I’ve often considered something similar for training and strength building - riding with additional wheel weight. I’ve just never found the right thing to use as ballast.
Kinda like runners who carry weights! Maybe attaching small clip-on weights to the nipple end of the spokes? Another way would be to simply add Slime to the tube! I’m sure that would net you at least three additional ounces! And afterwards, you should be able to squeeze most of it back out by removing the stem valve core. 
Now, you’re thinking… I was hoping for something that was easily installable and removable, easier than changing tubes.
These are at the top of my list so far…
- Pennies or washers and a dab of hot glue
- Household 14/2 copper wire
This is just what I’m planning to try. It would certainly be light, if it works at all! Lighter than the Schwalbe tyre you linked would be something like a Continental Sportcontact (hybrid slick) - even the fattest, 700c 38mm, is 550g.
My rough estimate of combining two of these to make a 36" tyre is that you’d use 2/3 of each 700c circumference, so 550*2/0.66 = 726g!! Yes please. Even adding a couple of hundred grams to overlap, patch, add extra bead strength etc and it looks feasible to get under 1kg. 
I wonder if leaving 10cms or so of bead sticking out to overlap where you cut the rest of the tyre, and then stitching that extra protruding bead onto the neighbouring bead of the other tyre would make a good enough join to mount a tyre and hold pressure? Otherwise you could always stitch on a complete, unbroken 36" bead from an old 36" tyre; that would be sure to work, beadwise - it would be a bit of extra weight though.
I wonder what effect the different natural curvature of the 700c tyre would have when bent outwards to make a larger circle? It may not matter at all, and with a bit of air in it I imagine it would fill out and shape up OK.
Sam
… or the lightest I can find is a Vittoria Ranonneur Hyper, available at 700c 38mm at only 440g (though not cheap). It’s kevlar bead too, but I don’t know whether that would make the splitting/joining process easier or harder.
By the 2/3 calculation (above) using these would result in a base weight for 36" of circumference of 581g…
Sam
How about split-shot fishing weights? Cheap, easy to install, easy to remove.
BTW, is it off topic to discuss how to add weight in a thread questing lightness? 
Wow, I hadn’t realized the weight difference was so slight. I’d previously been very attracted to the new rim, but I’m now thinking it’s not enough of a weight loss to justify the holes. Yeah, it’s probably still plenty strong, but the holes must inevitably add some vulnerability to the wheel build and tube. Besides, any significant dirt or wet riding could easily result in more than 3.2 oz of sand and mud getting into the holes and caking between the layers of the rim, so it could actually end up being heavier!
edit: Not to mention that the sand in the rim could be unevenly distributed, resulting in an unbalanced wheel. Although I haven’t seen discussion of this issue with respect to other drilled muni wheels, I suspect the effect could be exaggerated with the large wheel.
Basically I made the beads out of lots of loops of non-stretch ice fishing line and held them together with a piece of tape running their length and folded over. I cut the material at a 45˚ bias slathered a bunch of glue on the material and folded the beads into them sort of like this
_______
[ _______
[__________]
so that in the middle the end overlapped. At the seams I just glued and overlapped then folded, that is how it looked in the 24" tire I destroyed so I copied the technique.
waited for the glue to partially dry and mounted it up and pumped to moderate pressure to get the wrinkles out.
I glued on the tread I pealed off a tire (easier said than done), let that set then took it for a test run.
I couldn’t find the materials I wanted so I ended up using polyester material and contact cement. Next time I plan to use room temperature vulcanizing butyl rubber (I didn’t even know such a thing existed until that thread) and silk or nylon.
I really don’t think that joining two beads together would be a very good idea. Lets say that you are running a 1.5" wide tire with a diameter of 36" at 50 PSI Assuming that the bead hook does nothing there would be about 36 X 1.5 X 50 = 2700 pounds of force your beads are holding back. Even more for a wider tire at the same pressure. I would go with an old 36" bead or at least 30-40 wraps of 50# non-stretch fishing line/wire.
I drilled just the outer wall of my Coker rim before building it up. It still feels really strong but I drilled a rim the whole way through once (26") and it felt pretty flimsy after. If you have your wheel apart why not try drilling only the outer skin. It keeps the rim stronger than a full drill and you won’t need to switch to ha heavier rim tape. If the wheel is all built and you are happy with it I would only do it if you were bored and need something to occupy your time. The weight savings are not huge but probably noticeable.
Been there, done that, got the scars to prove it. Makes for an uber stable ride, just don’t go faster than you can handle.
BTW I made a tread about adding weight to a wheel for stability and it turned into a thread about drilled rims. Go figure eh?
I haven’t tried it, but if I remember reading Jobst Brandt (The Bicycle Wheel) correctly, you should be able to ride with a cut bead without any problems. So if you are cutting down two narrower tires to make a 36in tire, do you even need to connect the bead?
Interesting - could you elaborate? I don’t know a lot about clincher bead theory, and what makes it work, but I can’t find much on Brandt discussing clincher beads either (he seems to be a tubular kind of guy).
Do you mean that restricting the circumference of a bead is not important: that it will not pull ‘along its length’ but rather pull outwards from the rim, and simply being the right shape to hook the rim will hold it well enough?
Maybe this is how a Big Apple tyre stays on an old coloured Nimbus 29" rim. It literally falls off the rim until there is some pressure in the tube, but once it is on it seems happy to stay there.
Sam
Edit: This seems like pretty good evidence for the above claim: bead doesn’t need to be continuous to hold pressure! Tire with Cut Bead Pressure Test, by Damon Rinard
Lighter 36
Thanks for mentioning me on this thread.
I was mentioned earlier in the threads as I have drilled rims and tried all sorts of things to make the 36 lighter but I understand there might be a way of saving about 400g soon on the wheel build (secrets not devulged :)). Keep your eye on UDC sites.
Mal
Sam, It sounds like that’s it.
I think I read it in Brandt’s book, The Bicycle Wheel. I read a borrowed copy a while ago, and don’t remember all the details… If it wasn’t in the book, it was on a page linked from Jobst Brandt-Answers to Frequently Asked Questions about Bicycles and Bicycling (FAQ) or Bicycles.
The Tire Bead Test does look like a good demonstration. The inspiration for that test came from this thread, where Brandt says:
and that
So if I’m reading this correctly, the bead is just providing shape to the “hook” and it is the pressure from the tube pushing out on the hook that holds the tire on, not the circumference limit set by the bead. This makes sense, because the pressure is in all directions, not just radially out. That’s a good bit of force holding the hook of the bead into the hook of the rim.
I’ve never seen one of the Nimbus 29 rims, but that sounds reasonable. I think I’ve seen the same thing on an old three-speed bike.
BTW: Brandt is an advocate of treadless clinchers on 36 hole MA-2 (classic box double wall) rims for all road bicycling.
nordicnoel,
The Tire Bead Test is an impressive demonstration. It suggests (as you note) that you just need to overlap the main tire and glue it together. Special reconstruction of the bead (as suggested by Eric) would not appear to be necessary.
This construction strategy would appear to be fairly simple.
Scott
Just to visualise the shape of this idea, I mounted a 37mm tyre onto a wide 38mm rim. That’s at least as wide, if not even wider than 36 rims.
It looks fine to me. 36" tyres bulge a lot out from the sides of the rim, but this goes straight up in line with the edge, like road bike wheels do (which makes removing a wheel with brake pads fitted much easier).
Sam
My thought it, since all the 36er tires currently on the market (4?) are heavy, if they came out with a lightweight tire and tube, they would sell like hotcakes to most 36er owners. Doing both could cut wheel weight by a good 2 pounds. This could already be in the works; the uni community has been talking about, and wanting these changes for a long time, so hopefully coker and others have been listening!
I now have a little more than one year on my 36’er after about 4 decades on a 24. I have become more than a little frustrated with the massive wheel weight, particularly during a long out-of-the-saddle climb that I did last weekend.
Anyhow, I’ve been casting about online for who has done what to improve on the rotational weight of this wheel and came across Saskatchewanian’s very admirable sewn and bonded custom 36" Racing Ralph tire on another thread, which led me back to my bicycle racing roots, which included the necessity of having a needle and thread handy for tube repair. The beauty of tubular tires is when they handbuild a casing, they cut and glue it to whichever length the application requires, cut and glue a latex (super-light) tube to the same length, and sew the casing around the tube!
And the weight!?! The widest Cyclocross tubulars weight around 400g.
And my search for any discussion that connects unicyclists with tubular tires, landed me on this three-year old thread, which seems to have an abrupt termination, but a very enticing idea. Did you ever manage to get anywhere with the tubular maker on this project Unisk8r?
Either way, it’s clear that the tire is the primary answer to the weight problem. if I assume that a tubular tire can be acquired (and it wouldn’t be too difficult), the challenge would be the rim. Not such a large challenge, as the perfect tubular rim would be any rim of sufficient axial and lateral strength that has a smooth semi-circular surface to glue the tire onto. Isn’t this EXACTLY the type of rim already in use with non-pneumatic tires on both modern high-wheelers and over-36" unicycles!!! 
The rimstock for those wheels shouldn’t be so hard to acquire for a 36" application.
For that matter, I have seen John Foss comment before that the primary problem with 36+ is the lack of pneumatic tire. Tubular tires may well be worth chasing down for that application also!
I hope that unisk8r can bring the tubular tire maker that he was working with back into the loop, but either way, let’s get this discussion fired up again!!
Since installing the lightweight FOSS tube, and switching to lighter magnesium pedals, my 36er is noticeably lighter. So I took it to the local track to see how fast I could ride it in a 100 meter dash, from a standing start…with 110mm cranks. I hit 18mph fairly quickly, and covered the 100 meters in 13 seconds flat. I think I could have gone even faster, and the spongy rubberized track texture coating may have reduced speed a bit, but I was still flying! You can hear the wind getting louder and louder as my speed increases. Cool side-tracking bike cam too!
