Shopping for a 36er - Considering Nimbus Impulse 36 - Thoughts?

I’ve really gone in the direction of urban street riding lately, and I’m lusting after a 36er, as I’m currently doing all my street riding on a Nimbus Muni 26". But I’m also fond of riding off-road, so trying to make my Muni slightly more road-worthy (e.g., with a slim Big Apple tire and shorter cranks) isn’t an all-around solution. Better to serve both niches with different unis.

Now, as far as I can tell, the uni which best suits all my criteria on the surface of it is a Nimbus Impulse 36". It’s under $1000, and offers a disc brake and handlebar (which are two things it’d be nice to have, for my dedicated road uni build). And it’s black, rather than green or any more garish colour (which is in keeping with my preference).

My only hesitation, perhaps, regards the frame, which is somewhat unusual. That frame looks thin. It makes me a little leery.

Now, I could just go with the most conventionally trustworthy of all options, and get a KH 36". Surely, a sensible choice generally speaking. But no brake or handle out of the box. And adding them will bring the price a good deal higher. And frankly, I’d just be making the choice based on name and an unsubstantiated feeling of uncertainty regarding the Impulse frame.

It looks like the Nimbus Oregon also has this general category of frame design. Can anyone comment on its rigidity and structural integrity? I couldn’t find much addressing frame design in the existing Impulse owner threads.

Have you considered the Nimbus Oracle 36er? It’s got the disk brake as standard, and is the ‘conventional’ uni design. If doing any sort of big-ish drops on it I’ve read you need a steel hub, rather than the aluminum hub that comes with it as standard.

Hope this helps and welcome to the forum :slight_smile:

Edit: I’ve just realised you said no garish green. The Oracle comes with the lime green rim as standard, though the nice people at UDC will build it up with the black dominator rim, if you ask. Apart from that the frame is black, with decals on :wink:

Do searches for Nimbus Nightrider, not Impulse, and you should get a lot of hits. The Impulse uses the Nightrider frame, only they added a disc brake, and got rid of the Maggie bosses.

It is definitely not known for lateral stiffness. When I had a Magura on my Nightrider it would grab the rim when I would start cranking hard uphill. Other than that it was a cool frame and I had no problems with it. Moving the brake to the hub completely fixes the frame flex/brake grab effect.

There were a few of those frames broken as well. I seem to remember Corbin braking one after putting many many miles on it. I suspect that the force from the brake could have caused problems here as well. The only pics I remember of broken Nightriders was up near the top of the hoops (not far from where the brake would be mounted). So, maybe that’s why there is surprisingly little info about the Impulse. Moving the brake to the hub may have fixed the issues.

I’m not an engineer, but I don’t see how a design with about 10 separate welds could ever produce a frame that was stiff enough to adequately resist the forces created by a 36" wheel when the uni is turning at speed.

Space frame designs have proven themselves in many industries. In bicycles Alex Moulton made some beautiful designs that looked like a birdcage on wheels, and then let’s not forget Ducati motorcycles.

Agree with Juni- I love my Oracle 36er. A brake is a must on a 36er and a disc brake is the way to go. The price does start to climb when you start customizing the saddle, adding a touring handle etc. And I opted for the older black stealth 2 rim.

I’m not sure where I got ‘black dominator rim’ from…I meant the black stealth rim :roll_eyes:

I went for the green rim. I happen to think it looks sexy :smiley:

Fair enough, but isn’t a unicycle different (“unique”, so to speak) because it has only one balance point? I guess the complaints about excessive flex in the Nightrider/Oregon frames could be a result of those specific designs, rather than the space frame concept itself.

Great Input

Thanks for the quick responses and all the input folks. The Oracle does look like the solution within the Nimbus brand by which to get a more traditional frame but still get a brake.

That having said, something just occurred to me about the Impulse rather spontaneously - it’s a unicycle frame you could actually lock with a bike lock (i.e., not just the wheel - also the frame). Kind of a weird side-benefit to the unusual design.

Still plenty to think about. And still searching for all the information there is to be had on these 36" models.

Thanks, also, for the warm welcome.

I’m currently using an Impulse 36er for cross country but with some modification. The impulse handlebar system is not as versatile as the KH handlebar system.Also some people including myself had trouble with the saddle constantly loosening. :roll_eyes:

I replaced the Impulse handlebars and saddle with a standard seat post and a KH freeride saddle and KH handle bar system.

The Impulse hub was very creaky so I replaced it with an Oracle chromo hub.

I’ve had no problems with the frame, it feels rigid enough as I ride.:slight_smile:

The disc hub is very effective for steep downhill trails.:smiley:

I would not recommend the Impulse for cross country riding unless you’re prepared to modify it but that means spending more money…

Hope this helps:)


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Welds need not be a weak point in a properly designed structure.

One of the basic principles of efficient structure involves spreading the materials out so their strengths operate with favorable leverages. Space frames are the epitome of this principle, particularly where the construction material has a high tensile strength.

Interesting, thanks for that info.

I claimed earlier(speaking through my hat as a non-engineer), that a unicycle would not benefit from space frame structure since it had only one balance point (if “balance point” is even a legitimate concept). But now I’m thinking there are two: the point where each leg of the frame meets the axle.
Calling all engineers!

Thanks for the personal experience

Wow, thanks for sharing your personal experiences, Unibokk. Sounds like it’s a whole lot else than the frame which raises concerns here.