i have a freestyle unicycle and a trials unicycle,
and i only ever seem to want to ride the trials unicycle, that 19x2.5 tyre is just so perfect.
its great for jumping over people, toy double decker busses, off stages etc,
however with its 145mm cranks it idles like a slug, so bad that unicycling while juggling or escaping from straitjackets is pretty much out of the question, without some serious extra practice anyway. (i’m quite happy on my freestyle unicycle though apart from the old shoulder crunch, i’m sure all you escapologists out there know exacty what i’m talking about
i have been using my freestyle unicyle for shows but i want to be using the unicycle i ride every day, and i want to be able to jump off big things in my show
if i could have one unicycle that had 125mm splined cranks i could have the best of both worlds without bothering to practice.
or having to take two unicycles to a gig.
now there are a couple of ways i could achive this,
get a custom splined hub and 125mm cranks from dm unicycles
(they do exist i have seen with my own bare eyes)
get someone to make me custom 125mm cranks that will fit my profile hub.
any ideas who could do this?
get a kris holm hub /140mm cranks and have someone cut them down to size,
what would the engineering chalenges involved in this be?
to me it apears that the rectangular section of the kh cranks would make this much more possible than with profiles
would it be possible to do this and make sure that they wern’t misaligned? http://www.unicycle.uk.com/Images/Shop/khcrank.jpg
unfortunatly i have more time than monney at the moment so it looks like practice practice practice…
p.s. the chair jump is from when we perfomed as “the jeff or tony circus ridiculous” at “big in falkirk” jim didn’t die.
ive been down this road before and all your idea’s are ones that i’ve thought of before but getting things custom is so spendy.i would’nt even know where to start for some of that stuff.
i also thought about how far i could go on a Monty tyre with a Suzie hub and 125mm cranks?
i figured that if i didnt drop off huge stuff,say over 3 feet that it would be ok for a "freestyle/Trials hybrid unicycle.
i never built this unicycle but i have faith that it would be ok,and some what cheap.
I believe that the 150mm DM splined cranks are made by cutting down a longer crank and then welding the two halves back together. The same could be done with the Profile cranks. Both the DM cranks and the Profile cranks are hollow, round, steel cranks so the process would be the same for the Profiles.
Best bet would be to talk to DM about this. He’s done this crank shortening process before.
steve howard showed how he made custom profile compatible cranks. Although it sounds like he’s got some very expensive tools to do it, not to mention breaking some expensive profile bike parts to make the tool, I think he actually CNCd his own cranks as well, so we’re talking seriously silly. He also only made the holemaking thing out of a profile bmx axle, so it isn’t strong enough to make non-alu cranks.
I was told DM makes custom splined crank sets in pretty much any sensible length for not too absurd amounts of money, somewhat less than profiles.
Will Stevens has a prototype custom DM Monty to die for.
Flat crown, Monty Wheel, DM custom axle, 125mm cut down splined cranks, fairly low Q factor.
Will had already trashed several Unis including a splined Onza. Dave probably treated it as a challenge to build a uni that Will couldn’t break!
I don’t know what they would retail for, but the process of cutting down the cranks is very involved.
- cutting off the pedal end
- cleaning up the end so that there will be a nice radius join
- cutting down the crank
- cleaning up the crank to have a semicircular lip to mate with the pedal end
- building a jig so that you can present the 2 parts together at the perfectly correct angle
- carefully welding the parts together
- repeat for the other side
- machine off and weld over the chainwheel bolt hole
- send both cranks for rechroming
Phew - unless he has a mini production run like for the original DM ATU / Vortexes (Vortices!) I can’t see him wanting to make one-offs (unless you’re prepared to pay a “reasonable” amount for his time).
jagur i used to have a trials uni with suzue and 125 cranks but it died as soon as i started doing gaps over 1m and drops over 3ft.
i replaced the cranks a few times but square taper cranks just arent for jumping.
i didn’t realize that the dm cranks were cut down to 125mm.
is anyone going to be able to do it to a set of profiles for me?, obviously i lose the warranty.
i’d pay half again on the price of a new pair of cranks so im looking at about £200+
lots of monney…
what about the kh cranks? there much cheaper and look like theyd be easier to cut down?
well of course they did,i was saying that you could do more trialsey stuff on a uni like that than you could on a freestyle uni.if you get carried away with gaps N stuff then i wouldnt recommend it to you.i thought you might have a little restaint but i guess its hopless…
i do have restraint when i ride my freestyle unicycle, no drops over 1ft, no gaps larger than a person wide,
but give me something with a 19x2.5 tyre and i throw caution to the wind, if i think i can land it i’ll do it., thats why i spent so much monney on a trials unicycle.
besides theres no point in having a trials uni if i’m just going to do stuff that my freestyle uni can handle.
my basic problem is, i don’t want to be limited by my unicycle, i’d rather that my problems were all to do with skill,
which in a way they are already, perhaps i should stop trying to find easy solutions and just start practicing on my trials unicycle till i can escape from the straitjacket and juggle clubs
Re: take two unicycles to the show, not me…
Doesn’t anybody find 125mm cranks too short for trials? I certainly do… there
is just not enough torque there to land on rails and stuff.
The cranks I have on my Monty trials uni are cut-down mountainbike cranks. I was very lucky to come across two tubular steel cranks in a box of bits in a bike shop. They were both left cranks. I bought them along with 3 other 127mm aluminium left cranks for NZ$40. Cheap as!
Phase two was to cut 'em down and reweld them. This was done in a very low-tech way. The engineer tack welded the two halfs in place and moved around til they felt OK to ride. Then they were welded permanently. Cost = $80. One crank is definitely straighter than the other. The result was the strongest cranks I’ve ever owned - 5 foot drops no problem. But the downside is that its kinda hard to ride skinnies because of the wobble in the pedalling circle. Damn! Also they are both lefts, so the pedal on the right side has to be locktited on. Having two lefts makes getting decent pedals a headache.
In hindsight I should have gotten my local bike builder to do it - probably would have paid a little more but would have got a straight pair of cranks.
Re: take two unicycles to the show, not me…
apart from the obvious added hassle of carting two unis around, is there any other reason why taking two unis to a show is so abhorrent to u?
do u need the functionality of both during any single part of the performance or can u swop unis for specific tricks?
i’m just being the devil’s pragmatist here
u have both unis already so it strikes me as the ‘cheapest’ option
having two unis on the stage might also look better and at least give u some back-up in the (rare) event of equipment failure
sorry to rain on the tech-talk parade