A 1-page flyer came with it. On the bottom under “Things that can go wrong!” it states:
“Loose cranks, this is normally characterized by a creaking noise. Tighten the axle bolt immediately! If this is left loose it wil destroy the crank and hub. . .”
Today I heard a “creaking noise” but don’t know how to tell if this is a serious issue. It could just be the pedals or something else. Is there a distinct sound that a loose crank makes that is different from all other creaks? It only happens on the down stroke on the left foot and is rhythmic in nature.
Most creaks are just annoying, but it’s good to figure out what’s loose and try to tighten it. Candidates are the axle bolt, the bearing holders, the seat bolts, the seat clamp, or the spokes. It could be a pedal but that’s less common.
Yes. Exactly. It’s a rhythmic click/creak on the downstroke of my left foot. At first I thought it was the pedal… It’s very hard to tell. It only works when the uni is under stress with my weight on it. If I hold it and spin the wheel it doesn’t happen.
I’ve had a popping / clicking sound that turned out to be a loose pedal. Another time I had a very similar sound and it was a loose crank. The pedal would only make the sound under pressure, but I could move the crank with my hand. However, if I used my hand to turn the wheel under pressure (with the wheel on the ground just like as if I was rising it) I could tell when the pedal made the noise / feeling. So try putting your hand on the pedal and walking the uni under pressure to see if you can duplicate the creak and get a better feeling of it with your hand. It could also be the bearings either in your pedal or wheel.
Some of the Nimbus cranks/hubs had tolerance issues when the mfg went to a new manufacturing process, so it’s possible that the crank spines are a tad larger than the hub splines, which means the cranks needs to go one further.
So, if you have the standard Nimbus 6mm spacer, it’s possible you could try a 4mm spacer, which UDC would probably send you for free. To replace a spacer you’ll need a crank puller. For reference, a US Penny is 1.5 mm thick.
Spoke creaking sounds tinnier and is not as likely on a new wheel, esp coming from one side of the uni. Pedals don’t creak until old and worn. I guess it could be your ankles
Don’t oil your bearings, esp with WD 40, new bearings need nothing as they come pre-greased.
You could take your cranks off and rotate them 3 or 4 splines, and see if the creaking is still on the same downstroke - that would help you isolate whether the creaking is from the wheel/spokes, or the pedal/cranks.
Also, try riding the uni while sitting on it backwards - again, where is the creaking - has it moved from the left to the right crank? If so, it may be coming from the seat/clamp - or your riding technique is just heavier on one side than the other.
Hope that helps
Whilst this is true with everything done up tight, I know from my two wheeled cycling (ducks and runs for cover) that riding with a loose crank deforms it very quickly such that it will never be right again. (hence the warning on the unicycle instructions).
It might not be loose, it might just need cleaning and reassembling, or be something else making the noise, but if it is loose it does need sorting ASAP.