Nimbus Impulse 36 disk brake model

That does look pretty good. Think I will give that a try.

Yeah, my brake is still working fine, not that I’m great at using it yet. :roll_eyes:
I really like the idea of a disk brake, though, so it’s not as critical to keep the wheel very true. Including the disk on a production uni is a great option, and I’m seriously thinking about how to come up with an excuse to get me one of them new-fangled Nimbus 36ers. . . .


I’m commuting on my 29" and I like it but I’m starting to think about 36ers too… Is it correct to assume that I would only go faster by a factor of 36/29? If so, I think I should still be able to run out of UPDs at cruising speed… Is that your experience?

My experience is that although I managed to free mount my 36 the first day I rode it, I’m still not successful in doing so enough of the time to have tried commuting on it yet - although I have ridden across town several times. I do believe that ultimately the 36 will become my commuting uni of choice. Speed for UPD’s is not a problem for me yet, but I know I’m not riding it at full potential speed.

My comfortable cruising speed on my 29 was 8-9 mph, as compared to 11+ on my 36. It doesn’t seem like a big difference, but I never had a UPD on the road that I couldn’t land on my feet before I got the 36. The combo of going a tad faster, and being a touch higher makes for a new UPD experience. The upside is that even though my last UPD was painful, it seemed like slow motion. It seems like the smaller the wheel the faster it all goes south.

If you’re fairly nimble you can almost always run out of a 36er UPD. I’ve had only a few real wipe-outs.

You aren’t taking into account fixed gear bikes… a bike that can coast would be ridiculous without brakes… impractical and dangerous. With good technique brakes aren’t necessary in my opinion, granted that opinion may very well change as I get more use out of my body in the coming years, but I still think the only unicycle I’d ever run a brake on would be a Muni.

I ride 114mm cranks, good for speed, yet still just enough leverage that I can control myself fairly well up and down hill. I tried 89mm cranks and 112mm cranks but both felt too unstable on flat ground even and it became scary to ride at all above about 10mph.

I’ve learned you don’t really want to run out of 36’er UPDs, even at a low cruising speed of 11 or 12mph you risk injury to your feet/ankles/face. Unless I’m going about jogging speed I will always roll out of UPDs ever since I crashed at 22mph in an intersection a few years back. I rolled out of that and never considered doing any other way of saving myself in a UPD since. I’ve sprained both my ankles slightly a few times in UPDs at around 16mph when I cam off at an odd angle or just came off too hard and tried to run instead of roll. Definitely best to learn to just roll every time.

dished wheel strength?

I posted the following on the UDC new product launch thread, but thought I might also get interest here.

Another thought: Possible slight strength loss from dishing + slight strength loss from aluminum axle = too much strength loss? Or are 36er wheels so overbuilt that I’m just being overly paranoid?

The strength losses from dishing and the aluminum axle are not cumulative. Dishing the wheel will make it more likely to fail laterally (taco); weakening the axle will make the axle more likely to break. The axle being more likely to break won’t make the wheel more likely to taco, nor vice versa.

Whether either of these changes will result in failure remains to be seen.

Good point. Although the overall risk of failure may still be going up, but I agree it’s two separate issues.

Shadow handlebar pivotal seatpost “high tensile bolt”

I posted this in the “Shadow Handlebar first impressions” thread but I am so desperate for a solution that I thought I might also hit up some of my fellow Impulse owners.

The pivotal seatpost that allows for 4 x 6 degree adjustments via an integral “high tensile bolt” comes loose after even the most gentle UPD and ends my ride because you have to take the whole seat apart to tighten it and I am afraid that I am going to strip those teeth that allow you to tilt the seat back and forth. I prefer a little back tilt but put it right in the middle this last time in hopes that will keep that “high tensile bolt” from coming loose yet again. Beginning to wish it was non-adjustable like my old Nimbus 24" MUni which was rock solid. If it is loose, the shadow handlebar moves up and down while riding. Any tips? I am tightening that bolt as tight as I can but it keeps working it’s way loose!

I think steve said this already, but try blue locktight.


minimum inseam requirements

I don’t see the minimum inseam requirements for the Impulse on the UDC web site. Would 31" be enough to ride it without having to cut the frame?

Most likely you’ll need to cut the seat post down some. I just got mine this weekend and have about the same inseam as you I think, and I cut around 3" from the post to make it comfortable.

Keep in mind that the frame on the Impulse is essentially the same as the Nightrider, and that the seat post length for the Shadow Handle is 250mm. According to the Nightrider page, a 200mm seat post on the Nightrider will require an inseam of 32.5"-34.5" depending on the configuration. That would put you in the 4" seat post range for the Nightrider, and therefore require some trimming given the length of the Shadow Handle post.

Also, I don’t advise cutting the frame. :wink:

Impulse leg lengths:

Min Leg Lenth Cutdown Seatpost = 30.5" (77cm)
Minimum Leg Lenth = 35.5" (90cm)
Maximum Leg Lenth = 38"( 97cm)

As I posted before, I would also suggest some locktite. I would also apply greese on the joint and bolt head/slot. This will help it seat and hense tighten up.


minimum inseam requirements

I opted for the 4" seat post on my Impulse and it was a perfect fit (with 2" stuck down in the frame) without cutting. I am 42 years old. I weigh 160 pounds. I am 5’ 9" (mostly torso) so my jeans are 34 waist 30 length. My wife helped me measure my inseam (it was a sight to be seen, her with the ruler and me holding the family jewels) wearing (5.10 impact 2 high) my riding shoes and the best we could estimate my inseam is 29" so 31" should be fine. I was really worried about being too short to pedal (would be a shame to have to cut down the frame on a $1k unicycle) so I opted for the dual hole cranks thinking that if I was too short for the 150 holes I could try the 125 holes but, as I say, the 150 holes are a perfect fit until I build the leg strength to muscle the hills of Kentucky with 125’s. One last thing and this is my first 36er so take this 2nd hand knowledge with a grain of salt but it is my understanding that the minimum inseam requirements of the Impulse and Shadow handle are lower than the Nightrider with T7 handle. Get this uni! You will NOT be disappointed!

Here is a link to one of the older threads that I used to make my decision.

OK, I am the guy who should not have started this thread.

Has anyone ridden the Nimbus Impulse disc? What do you think?

My Impulse needs a 100 mile checkup

It is normal for cranks to settle over time, and to need a bit of tightening after an initial break in period. 100 miles and a few weeks in, I am hearing/feeling a clicking noise in my right crank (KH Moments 125/150). Ruled out pedals as the source with a new set of SpeedPlay Drilliums. Sweet! Now I need to tighten the crank bolt but I want to buy a torque wrench first. My question is: what level of torque do you recommend for the crank bolt on this aluminum spindle? I want to make sure that I have it as tight as necessary (without doing any damage) to get it to seat.

25-30 foot-pounds.