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silverfridge
March 29th 06, 03:09 PM
when i last change my tire, i was doing it in bad light, and because i
couldn't feel any resistance, i overtightened the bolts holding the
wheel to the frame,
u know the ones, that tighten that U shaped bit of metal over the
bearings and connects to the frame>

anyway, that was a while ago, and now i notice that the U shaped bits
of metal are a bit bent,and the screws holding the frame and the U
together are bent, but the frame part where the screws fit in is okay.
could this cause problems later on?
My uni is a Qu-ax 24" Muni, and i ordered it from NZ i live in WA

also, i broke a bolt in my seat, one of the bolts that tighten the
saddle to the post, and now i have threee, how can i go about fixing
this, and will this be a big prob either?

cheers, and yes, i think i do have a slight overtightening tendency,
but thanks a lot for any help u could give, in advance
:)


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silverfridge

GOD SPEED!
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icon
March 30th 06, 01:12 PM
Wot, no replies?

I suppose it goes without saying that if you've overtightened the bolts
to the extent that you've bent the lower bearing housing you've got
problems now, not later.

The rather odd design of the bearing housings on unis invites
overtightening, which pinches the bearings into a slightly oval shape.
Since the inner bearing is constrained to be round by the shaft it's
on, the bearing will be stiff and wear out quicker, as the balls have
to squeeze through a smaller gap than they're designed for.

I don't think there's any merit, with nyloc nuts on bearing housings,
in tightening much beyond finger-tight.

No doubt Qu-ax can provide a couple of replacement bearing housings and
some bolts.

When I get around to making a uni[1], it'll all be much better designed
- properly machined bearing housings that extend the full circumference
of the bearing, less a couple of thou.

Regards
John

[1] Ha!


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icon
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Jim
March 30th 06, 02:01 PM
you can get replacement bearing holders from 'unicycle.com NZ'
(http://tinyurl.com/de27z) (i couldn't find any on Unicycle.com
Australia's site). these come with replacement bolts (but these might
not be long enough to fit 42mm bolts).

Replacing a bolt on a saddle can be a pain to fix if you don't have a
Fusion style saddle with removable cover, but it can be done. You have
to strip the saddle down replace the bolt and build it back up again.

jim


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Jim
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flyer
March 31st 06, 04:16 AM
icon wrote:
>
> When I get around to making a uni[1], it'll all be much better designed
> - properly machined bearing housings that extend the full circumference
> of the bearing, less a couple of thou.
>
> Regards
> John
>
> [1] Ha!



The 'KH' (http://www.krisholm.com) has this. Works really well. I
usually keep the bolts on my non-awesome bearing holders to a light
push on the end of a wrench that's screwing them on. Haven't had any
problems (too loose nor too tight) yet.


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flyer
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skicker
March 31st 06, 01:16 PM
I had the same problem on my qu-ax muni, the bearing holders and bolts
that came with it seemed to bend quite easily. Got some new ones from
unicycle.com and that sorted it, plus they seem a bit more sturdy.

I did try to find some kind of tube which i could put round the bolts
in the gaps between the holders, but never found anything suitable. The
idea was to keep the gap even either side and add a bit of support to
stop the bottom bit bending.

I agree that the ones on the KH frames are much nicer and wrap right
round the bearing, solving this problem.


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skicker
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