Flatland wheel build

Unicycles and Equipment
21

My worry is about how long a shaved tire will last, seems like there isn’t a lot of rubber once the knobbys have worn off.

22

Try getting some worn out trials tires off the trading post. I would bet there are at least a few people who would send them for the cost of shipping. That way you don’t need to worry about how long they last.

23

Can you say how much this tire marks up the sidewalk vs. other tires? I have a Maxxis Grifter (2.1" wide) on my basketball unicycle right now that’s getting worn and was thinking of trying something wider on my KH flatland rim (47mm wide).

24

This is after 15 min of idling…

After closer inspection, it turned out to just be dust from the tire. I grabbed my broom and it easily swept away, leaving no marks. It doesn’t leave any marks on the street.

I went out on the tennis courts near my house (not supposed to ride on them) it left marks immediately on the painted surface, so I got out of there.

CIMG1976.JPG

25

Thanks for the info and the photo! I went ahead and ordered the 2.35" wide version as well and I’ll see how well it works for my purposes.

26

OK, I’d like to take this project on. I want to build a 20" flatland rig using a grifter tire.

I need a parts list.

  • hub? What kind? I am a total newbie when it comes to building wheels
  • rim?
  • spokes?
  • rim tape
  • spoke wrench
  • tire: maxis grifter
  • tube? Any 20"?

I have cranks, pedals and frame.

27

Hub: The nimbus isis 36hole is the hub I’ve been going with. It’s strong (when you hold just the hub in your hand you will understand), it’s relatively inexpensive, isis - so all your cranks will fit.

rim: I can’t be much help here, I looked for the widest rim I could find for bmx wheels. Alex dx32 would fit the bill, it’s pretty cheap as well.

spokes: straight gauge 2.0 mm is what’s typically used in unicycle applications.

yup, rim tape and spoke wrench, you have the tire handled.

tube: I just put a regular bike shop 20x2.1 tube in my trials wheel. We’ll see if that holds. I think a regular tube is fine, you may be able to find a heavier duty one, but it’s probably not a big deal.

I have wheel smith spoke prep for the threads of the spokes, it helps the threads lock to the nipples. Like Jtrops said you can use boiled linseed oil i guess as well, I have it laying around because I build bike wheels too.

I have this
http://www.amazon.com/The-Art-Wheelbuilding-Reference-Wheelaholics/dp/0964983532
plenty of info out on the internet as well.

Go for it, it’s good fun.

28

RIM: Look for a flatland freestyle rim, or a Mod Trials front rim (406 BSD). I’m not sure that double wall is called for, but if you are worried about strength a DX32 is a solid choice.

HUB: You can use any hub you’d like. Probably an ISIS Nimbus would be about perfect.

Spokes: For your first build I recommend 14g. spokes, with no butting and brass nipples. Butted spokes are great, but they have a tendency to twist more than plain gauge spokes.

Tape: If you use a single walled rim a plain rubber rim strip is all you need. If you have cuttouts, or a double wall you will need a strip that can hold pressure such as a plastic strip, or an adhesive rim tape like Velox.

Any tube will work.

If you get your spokes and tire from Danscomp you can get the shiping for free. They always have a $30 free shipping promo, but you have to look for it a bit.

http://www.amazon.com/RavX-TX2-Hook-Spoke-Wrench/dp/B0060ZCN40/ref=sr_1_1?ie=UTF8&qid=1402084915&sr=8-1&keywords=ravx+spoke+wrench
is the RAVX.

29
30

That nipple driver would do the trick. I have one that I made by filing the end of a Klein rapidrive philips screwdriver. I basically just made a flat blade with a 3mm pin in the middle. The cost was $8 or $9, and about 15 minutes of handiwork.

If you buy the spokes from Danscomp nipples are included. Most suppliers at this point sell the nipples for an additional .10/piece. That makes Dans price even better.

You’re right about the DX32. It seems like it went out of production a few months ago. I would look on EBay or Pinkbike. There are a couple of trials (bike) guys that sell them. Just make sure you get the 406mm BSD for the standard BMX 20" rim, and not the 387mm of the Mod Trials rear rim.

Also, there are other wide BMX rims worth a look. Check out the options on Danscomp. They also usually have a few rims in the sale section to help keep the cost down.

31

Would something like this work?
http://www.danscomp.com/products-PARTS/420034/Rhythm_BMX_Expert_15_Rim.html

32

Danger! 28 hole rims there. Good luck finding a unicycle hub to match.

These look pretty boss to me, though the holes might not fit your plans if you intend to run high pressures:
http://webcyclery.com/product/echo-urban-20-front-rim-1827.htm

33

Also, the rim you found on Dans is only 21mm wide. If you use the filter choose 1.75" for the rim width, and 36 holes for the drilling, and you should find rims that are at least 30mm wide. In general, when rims are referred to in inches it is the tire size, and metric is the rim size.

The Echo Urban rim is a great rim from everything I’ve read. If you get that you will need a 32h hub.

34

Aha! Yes, you’re right about that. My knobbies had just been ridden down to a nice smoothness when suddenly threads started showing through and I began noticing a lopsidedness in my tire from too many sidemounts on only one side. Can anyone recommend a fat, smooth tire for a KH20FL rim?

Also, would this be a good moment to change my clattering KH hub? After six months of mostly gentle riding, it now makes movements that I not only hear but feel. When I ride SIF, the noise turns heads from at least 20 meters away, as if riding around on one wheel weren’t weird enough! UDC was kind enough to send me a replacement, but it’s the same brand, and from what I’ve read, destined for the same noisy deterioration. I did talk to a girl the other day who said her Nimbus hub had done the same thing, but only after two years, rather than two weeks.

35

Unfortunately there are no really fat 20" tires (like trials tire fat), most 20" tires are bmx tires, so usually they are 1.95 or 2.1, there are some 2.35 but that is about it. I have a demolition momentum tire on my freestyle setup, it’s 2.35 wide. I have no complaints with the tire so far.

After holding the basic nimbus 36 ISIS hub in my hand I can’t imagine the hub would ever make noise, it’s like a solid piece of steel. More than likely her bearings began to make noise? Mine have all been going strong for 4 or 5 years and showing no signs of weakening.

36

If your frame can handle it there are some 3" tires: the Kenda flame, road hog, and kraze. Also, Odyssey makes a couple of 2.4" freestyle tires worth a look. Those three inchers are heavy, and have a flatter profile. I’d say the Odyssey tires are more up your alley. I think the 2.35/2.4 size has a lot of volume. Maybe even as much as a 2.5. Consider that there is much less tread, and the tire usually come close to the nominal size across the tread. The extra space has to be taken up with volume.

37

So should I get this rim? Looks like a good price. What do you mean by higher pressures? I want to use the Maxis Grifter which comes in a 1.85 and a 2.10. Looks like Kris uses the 2.10 on the KH20FL: http://krisholm.com/en/gear/unicycle/kh20fl. Max pressure is 110, which I would never ride on. Probably more like 30PSI?

38

If you want to run 30psi I would look for a tire with more sidewall support. The grifter is a folding tire, and a lightweight. My CST Operative would be a better choice for a lower psi setup. You don’t want to fold the tire and get pinch flats. The Echo should be just fine with 30psi, and probably 50.

Btw the operative seems to be a wire bead cheaper version of the grifter. They are both made by CST.

39

Can you explain why some hubs have 32 vs 36? Are 36 hole hubs stronger? Are 32s lighter? Is this the hub I’d want with that echo rim? http://www.unicycle.com/unicycle-hardware/hubs-and-hub-assemblies/nimbus-32h-all-steel-disc-hub.html and will that fit in my Impact Regent frame?

Also I really have no idea what PSI I’d run. I run about 15 on my trials wheels when doing flat, a bit less I think when dong trials. I am a pretty light guy at 140lbs. So probably nowhere near 30PSI on the grifter I imagine, but again not sure.

40

Perhaps someone else who’s been around unicycles longer has a better answer, but I’ve assumed that 36 spokes is a de facto standard carried over from consumer bicycles. Yeah, 36 would be marginally stronger, and 32 marginally lighter. You could even go with 48 spokes if you were really worried about strength, but that seems like way overkill for you and what you’re considering. My guess is that 32-vs-36 is more about not wanting to have to carry double inventory on every part, and (mostly) having setted on 36.

You haven’t mentioned wanting a brake. This one one seems more like it:
http://www.unicycle.com/unicycle-hardware/hubs-and-hub-assemblies/nimbus-wide-isis-hub.html

Not sure what the “wide” business is about there. But it does say “standard 100mm spacing.” Maybe call them or use online chat to double check?

Yeah, I’ve run well over 30 psi with the cutout KH Flatland rim on my Reagent with no problem. Occasionally someone will mention 100 psi in a Hookworm for flatland riding. That might be something to worry about.