Well, that didn’t take long. After barely a year on my cheap
Taiwanese uni, I have managed to create the classic stress fractures
where the screws pass through the frame into the lollipop bearing-
holders.
I have a couple of questions:
About how long might the frame last (under plain riding use) after
the cracks appear? Is it essentially toast, or have people ridden
them like this for years?
Has anyone fixed this sort of problem? I’m thinking that a length
of stronger tubing fitted over the fork-end and drilled for the
bearing-holder bolts would get me going again. Has anyone tried
this, or some other fix?
============================================================
Gardner Buchanan <gbuchana@rogers.com>
Ottawa, ON FreeBSD: Where you want to go. Today.
Its not a matter of when it will fail. It already has.
Replacing/repairing the frame now might save some other hardware from damage
or avoid it crapping out on the next enjoyable ride.
well what i did, was take some big pipe plyers things, and put my bolts on alittle, then when im tighting them up, stop and squeeze the frame togother (if your frames doin the same thing as mine did, which was spread outward at the bottom.) or what i ended up doing was i build myslelf a new frame, with some pipe and flatbar, if you have access to a shop and tools, and somone who can help you out, you could make yourself a new frame. But after the stress cracks come, i think that what comes next is chips of frame fall out when you take the bolts out, thats what happened to my frame. But if you just street ride, no drops, hopping, stuff it should be fine for awhile, till you can get yourself a new frame, or build one. Sorry wasnt much help, but maybe it will give you a sorta idea of what you can do or somthing.
Oh yeah if you wana see some blurry pictures of my frame go to the gallery, and look for Brokenframes Picture thing, it has some blurry pictures of what i made.
They have Torker, United lollipop, United main cap, Savage. You should be able to find yours and it will be cheaper and better than trying to repair stress fractures of undetermined propogation length.
go with what Harper says:for only $30 bucks you could get a Torker frame,thats peanuts!pound the bearings out of the lolly pops and use them in the main caps.
but it woulnt be as fun to buy somthing off the net, then as to experement and build a new frame. its fun, and it makes you feel it good when your finished.
I just bought a welder last week, and am teaching myself to weld. I’m going to weld some brake bosses onto my muni once I get a little better. cheers… Joe
Go for the brake bosses, Mojoe! (once you’re relatively skilled with the welder, of course.) I welded bosses on my Savage muni and am using Maguras on it. Yes, I said “Savage muni”. I had to fix the exact same problem mentioned above (and replace every part on the thing exept for the frame) but now I got myself a light, cheap frame that has seen many miles of rough, technical singletrack.
Gardner, Method 1:
find some pipe that fits tightly on the fork legs.
cut off a coupla inches for each leg.
pound the the pipe onto each leg.
redrill your bolt holes.
install bolts and tighten them.
have somebody weld all the way around the top of the pipes.
I don't know if the welding is necessary but it'll definitely eliminate any creakin'. Also be aware that by adding pipe there you may create a problem with pipe hitting spokes or bolts hitting cranks. I didn't have a problem but it was close. Check before you commit.
Method 2:
Call Unicycle.com.
Order new frame.
Torker is nice but doesn't take a fat tire (nothing over 1.75"). Savage is crap unless you make many modifications (don't buy it). I haven't experience with any others so I will not comment about them.
Notes:
I used Method 1 and it was easy and it worked. However, because of frame limitations (need 2.6" tire) I will probably soon employ Method 2.
> About how long might the frame last (under plain riding use) after
> the cracks appear? Is it essentially toast, or have people ridden
> them like this for years?
In my opinion it was toast when you bought it, and only a matter of time
before the frame would fail. The amount of time is entirely dependent on
your weight and type of riding.
> Has anyone fixed this sort of problem? I’m thinking that a length
> of stronger tubing fitted over the fork-end and drilled for the
> bearing-holder bolts would get me going again.
That would be shoring up the same design flaw. I think I have seen a fix
where someone used a pair of seat post clamps there, instead of the two
bolts. I’m not sure if it was a frame fix, or a design method used by some
riders in Puerto Rico to build custom frames. Try it out and see if there
are clams that fit.
> Method 1:
> - find some pipe that fits tightly on the fork legs.
> - cut off a coupla inches for each leg.
> - pound the the pipe onto each leg.
> - redrill your bolt holes.
> - install bolts and tighten them.
> - have somebody weld all the way around the top of the pipes.
> I don’t know if the welding is necessary but it’ll definitely eliminate
> any creakin’. Also be aware that by adding pipe there you may create a
> problem with pipe hitting spokes or bolts hitting cranks. I didn’t have
> a problem but it was close. Check before you commit.
>
I’m off to “the Metal Supermarket” tomorrow to find some tubing
that fits the bill. The forks are 22.2mm (7/8ths inch) OD, so
I should have good luck with a chunk of bicycle down-tube or
something like this. I talked to a gent who would do a TIG
weld to hold the tube in place. My feeling is that the weld
would just weaken the (altogther too thin) tubing at the weld
line though. Perhaps a few spot-welds part way down would be
an idea.
I like Harper’s idea of a couple of seat clamps. That does
feel like a temporary hack though. If I’d have had hose-clamps
handy, I’d have stuck them on, just to see how long the lasted.
Once I’ve got a ride again, I’ll start looking for a permanent
replacement. Landing anything in Canada from the US costs the
earth. Any sort of frame or Uni costs more to ship, tax and
broker than the darned thing costs in the first place. My buddy
Darren Bedford in Toronto would likely be my choice for sourcing
a uni.
============================================================
Gardner Buchanan <gbuchana@rogers.com>
Ottawa, ON FreeBSD: Where you want to go. Today.
[QUOTE] Originally posted by John Foss
I’m not sure if it was a frame fix, or a design method used by some riders in Puerto Rico to build custom frames. Try it out and see if there are clams that fit.
>>>> ‘Clams that fit’? Is this because unicycling builds up your mussells, or is this just a red herring?
More seriously, what about jubilee clips (US = hose clamps?) around the ends of the fork legs if they’re flaring.
Also, on my old lollipop-bearinged uni, the screws went into the lollipop ‘stick’. On my later one, bolts go right rhrough and spread the load better. Could you modify?
> I’m off to “the Metal Supermarket” tomorrow to find some tubing
> that fits the bill. The forks are 22.2mm (7/8ths inch) OD, so
> I should have good luck with a chunk of bicycle down-tube or
> something like this.
If your repair will rely on the same two bolts-in-the-side-of-round-tubing
approach, be sure to add some washers that are contoured to be flat on one
side and match the curve of the tubing on the other. I think if you use
these from the start it will add a lot of life to one of those frames.
> I like Harper’s idea of a couple of seat clamps. That does
> feel like a temporary hack though. If I’d have had hose-clamps
> handy, I’d have stuck them on, just to see how long the lasted.
Nice going, Harper! Hose clamps would definitely be a temporary,
get-you-home fix. Seat post clamps would be stronger than any form of two
bolts coming in from only one side. The problem will be do they fit. They
have to be the right size, and yet not too fat to interfere with the wheel
or cranks. But I know clamps have been used in that location before, so
there must be a workable combination.
my first uni was a [hardly] used savage 24" via ebay, and after a couple months of medium riding mine did the same thing. the frame actually cracked twice, leaving a strip of metal loose both between the bolts and under the bottom bolt. ascii time:
O==O=|
______|
so my solution was twofold: order a united/monty trials from unicycle.com for my primary uni, and secondly as a stopgap solution, to take out the strip of metal that was loose, put the top lollipop bolt in as normal, and then clamp the frame down against the lollipop with a screw-on hose clamp. so far it’s held up quite well to the occasional riding when i need a 24"
there’s enough clearance between the clamp and the crank as it swings past, that i’m not concerned at all
In article <mailman.1022617556.29025.rsu@unicycling.org>,
John Foss <john_foss@asinet.com> writes:
>
> If your repair will rely on the same two bolts-in-the-side-of-round-tubing
> approach, be sure to add some washers that are contoured to be flat on one
> side and match the curve of the tubing on the other. I think if you use
> these from the start it will add a lot of life to one of those frames.
>
Yes. My plan is to take a piece of thick-walled tubing, cut out
a little section of perhaps 60-degrees and 40mm tall, drill it for
the bolts and grind a flat surface on the outside for the heads to
mate to. To do this, I will need a new hacksaw blade and plenty
of band-aids.
============================================================
Gardner Buchanan <gbuchana@rogers.com>
Ottawa, ON FreeBSD: Where you want to go. Today.
Hose clamps would definitely be a temporary,