As a point of interest could I ask what the frame material for the other steel frames is and what the advantages are.
thanks.
Although CrMo is very tough it is very dense and hence is of course heavy. So unless you accept the weight disadvantage and make thinner or smaller tubes you end up with a very heavy frame. When the tubing is made very thin it is prone to damage from dents, once dented the strength is considerably reduced. It is also more difficult to join and the welding is often badly done as you need to prehead, slow cool and post weld treat, so this precludes mig welding and means that they should tig welded. When it goes wrong, the tubes just fall apart, note the koxx frames or the tops of the tubes on the legs. This is not to say anything about cost… CrMo is considerably more expensive to produce and use. The high carbon steel that we use on unicycles is strong enough to take the bashing we give it and is cheap.
Roger
There are many threads about KH hubs that make loud creaking noises. I don’t know for sure whether this problem is dangerous, but only a few people seem to have managed to fix it. A guy at UDC told me that Nimbus hubs don’t creak because they are designed differently. I have no personal experience with Nimbus hubs, but if they are indeed made of the same CrMO, I would guess they are probably more reliable.
I was wondering why Nimbus is still using the D-brake concept. All other companies with muni frames (KH, Quax, Triton, recently also Mad4One) have the disk brake mount welded to the frame. Any plans in the future to change this?
Let me ask the question… who was the first company to produce a disc brake mount on a production frame?
Nimbus currently find the d’brake more accurate, versatile and adaptable than mounting the brake on the frame.
Ooh! I know this one. It was Nimbus! Wasn’t it on the earlier Oregon frames?
I think the D-brake is a good design. You bend it or brake it, you get another $30 D-brake instead of a $150 frame.
I just prefer not to bend or brake the disk mount at all ;). I have not heard of a failure with frame mounts, can’t say that for the d’brake (but please correct me if I’m wrong). In any case the d’brake is awesome to retro-fit older non-disk frames.
Yes, I take your point Ben. Although the frame mounts do occasionally bend, it is rare. What you don’t see as customers is that they are a nightmare to setup and align the frame mounts correctly on frames; this of course costs time and money. This is due to the welding and hardening process. This is not only a unicycle problem, but a bike one too. The bike industry has several different solutions, one is the development of adjustment in the adaptors, others use machine inserts and others post construction machine spotface the mounts. The D’brake works first time, every time. We are lucky in the unicycle world we have a 100% accurate machine surface to use as a datum… our bearings.
The occasional failing of the d’brake with 200mm disc’s is a pain and we have taken action on this already. The instances are considerably reduced now, but you can still bend/brake them as this is the designed fail point. Hence it is replaceable.
Roger
Comparing today’s Nimbus 36" to the KH 36" for drops, is there much difference?
Is the hub the #1 concern for drops (I’m 190 pounds)?
Is the rim or number of spokes the #2 concern for drops?
Maybe a drop wouldn’t be the worst situation in which to discover that your uni just acquired freewheel capability -I assume that’s what happens when your hub fails, as mentioned here. If it failed while you were speeding along on your 36, that might be more dangerous. It’s kind of surprising, given what’s been posted about KH hubs over the last few years, that anybody would choose one over Nimbus or some other brand. Nurse Ben, who started the thread I just linked to, says he had 3(!) KH hubs that failed.
Apparently the problem is that KH hub bodies are pressed onto the spindle and epoxied, and will eventually come loose, whereas the Nimbus hubs are simply welded.
Both wheels have the same number of spokes and the rims are larger versions of their smaller counterparts as far as i know.
One thing to be aware of is that the oracle 36 uses a lightweight alu axle in the hub that is not designed to take the abuse that you would throw at a smaller muni. If you were planning to do serious drops you should contact UDC to see whether they will part swap the hub for one with a CrMo spindle.
Some people say that the 48-spoke wheel on some unis (such as Quax) is stronger, others seem to think not, and that more than 36 spokes is just extra weight. Not having had the opportunity to compare and destroy 36-spoke and 48-spoke wheels, I don’t have my own opinion.
I would think that a larger diameter rim might handle less impact than a smaller one, but there’s a Unigeezer video showing a pretty massive drop on a 29. Unlike KH hubs, KH rims seem to be very high quality, though there are undoubtedly people on this forum who’ve tested them more rigorously than I have.
Unless you get an aluminum/titanium hub I don’t think you have to worry about the hub for drops.
48 spokes will build a stronger wheel than 36. The quality of rims is so good anymore that you can get away with fewer spokes without compromising wheel strength in an important way. There is a point of diminishing return and that has to do with the strength/stiffness of the rim (read: weight) and its ability to transfer the load around the circumference. In other words, as the wheel gets larger you should use more spokes to maintain the optimal spacing between the nipples. if the space increases without also increasing the strength/stiffness (weight) of the rim you will end up with a weaker wheel.
So in the end wheel strength comes down to geometry. The best is to have the widest hub flanges possible without any offset, and to have a stiff rim with the right number of spokes under even tension.
Nimbus vs Kris Holms
I sold my Nimbus and had fun on it, but unless money is a factor go with the Kris Holms. They are build a lot better and are lighter and look better, not that , that matters. I have 2 Kris Holm unicycles and love them. Thinking on getting another one. I live in Wadsworth and if you want to try my 26 inch on my concrete drive, over 125 ft of it, you are welcome to come over anytime. If you noticed I am a little younger than you are. (66). I’ll send you a Message.
Beg pardon?
Are they not made in the same factory?
Not all the components are made in the same factories, although most are.
In manufacturing quality terms they similar.
KH is lighter than the Nimbus Oracle, although it does not have a brake fitted. I am not sure if there is much difference when the KH has a brake fitted. The Oracle has the lighter frame.
Roger
Can’t believe I missed this, but the stock KH 36 is wayyy better for drops. The both have the exact same rim and spokes but the nimbus has an aluminum hub that is great for road use but is liable to wear out/break if you are rough on it.
I am giving bogus information aren’t I. I was referring to the 26" not the 36". Shmolagin’s comments are right. If I were looking at the strengths of the 2 products, the 36" Oracle is a road unicycle and the 36" KH is an offroad unicycle.
you GO! Thanks!