Rim wear



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Phileas

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I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
read in an earlier post, it's time to replace it.

The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
there's not much braking required.

It's a Mavic Open Pro and I've been using Shimano blocks (I've just started using Kool Stops).

Any comments?

Phileas
 
Phileas wrote:
> I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
> read in an earlier post, it's time to replace it.
>
> The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
> there's not much braking required.
>
> It's a Mavic Open Pro and I've been using Shimano blocks (I've just started using Kool Stops).
>
> Any comments?

Maybe they're slightly concave from new?
 
Originally posted by Phileas
I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
read in an earlier post, it's time to replace it.

The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
there's not much braking required.

It's a Mavic Open Pro and I've been using Shimano blocks (I've just started using Kool Stops).

Any comments?

Phileas

Is all the factory machining gone?
Do you clean your rims and brake shoes regulary, particularly after wet rides?
I think I would try pushing the rims further.
Many of the newer rims come with a wear indicator. The one I measured on a handy Bontrager rim shows 1 mm.
 
On Sun, 15 Feb 2004 14:30:53 +0000, Zog The Undeniable <[email protected]>
wrote:

>Phileas wrote:
>> I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
>> read in an earlier post, it's time to replace it.
>>
>> The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
>> there's not much braking required.
>>
>> It's a Mavic Open Pro and I've been using Shimano blocks (I've just started using Kool Stops).
>>
>> Any comments?
>
>Maybe they're slightly concave from new?

Does the measurement change without tire pressure?
 
"daveornee" <[email protected]> wrote in message
news:[email protected]...
>
> Is all the factory machining gone?

Long gone!

>Do you clean your rims and brake shoes regulary, particularly after wet rides?

No. I mainly commute. In the winter, most rides are wet to some extent.

> I think I would try pushing the rims further. Many of the newer rims come
with a wear
> indicator. The one I measured on a handy Bontrager rim shows 1 mm.
>

There's no wear indicator. Unfortunately, I've lost some confidence with both my rims (the front has
an alarming groove in it caused by allowing the brake pad to wear down to the metal body!). I've
replaced both the wheels with spares until I buy new rims and build a couple of replacement wheels.

I'm wondering what rims to buy. I've read a lot of bad stuff about Mavic rims but they seem to be by
far the most available.

Phileas
 
"Phileas" wrote:
> I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
> read in an earlier post, it's time to replace it.
>
> The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
> there's not much braking required.
>
> It's a Mavic Open Pro and I've been using Shimano blocks (I've just
started
> using Kool Stops).

Was there a lot of embedded grit and aluminum in the Shimano pads? That would do it.

Art Harris
 
"Arthur Harris" <[email protected]> wrote in message
news:[email protected]...
>
> Was there a lot of embedded grit and aluminum in the Shimano pads? That would do it.
>

Probably - that's why I switched to Koolstops. In the short time I've been using them, they don't
seem as gritty as the Shimano pads.

Phileas
 
I wrote in message news:[email protected]...
>
>
> I'm wondering what rims to buy.
>

I'll probably put another Open Pro on the rear unless I find another rim which allows me to re-use
the spokes.

Phileas
 
Phileas wrote:

> "daveornee" <[email protected]> wrote in message
> news:[email protected]...
>>
>> Is all the factory machining gone?
>
> Long gone!
>
>> Do you clean your rims and brake shoes regulary, particularly after wet rides?
>
> No. I mainly commute. In the winter, most rides are wet to some extent.
>
>> I think I would try pushing the rims further. Many of the newer rims come with a wear indicator.
>> The one I measured on a handy Bontrager rim shows 1 mm.
>>
>
> There's no wear indicator.

Wear indicators are nice, but you can determine wear the old fashioned way. Measure your rim with a
caliper, sidewall to sidewall, and compare it to the spec for a new one. A little concavity is not
necessarily a problem -- sidewall thickness is.

Matt O.
 
try ceramics. they're designed specifically for high wear life.

Phileas wrote:
> I just measured the concavity on my rear rim with a dial gauge and it's about 0.6mm. From what I
> read in an earlier post, it's time to replace it.
>
> The thing that surprises me is that it's only done about 5 or 6 thousand miles on a commute where
> there's not much braking required.
>
> It's a Mavic Open Pro and I've been using Shimano blocks (I've just started using Kool Stops).
>
> Any comments?
>
> Phileas
 
"jim beam" <[email protected]> wrote in message
news:[email protected]...
> try ceramics. they're designed specifically for high wear life.
>

Normally, I don't recommend ceramic rims even though I own a pair. BUT, in this instance: wet
commuting, it makes sense.

Just make sure you get some ceramic brake pads.

Mike
 
"Phileas" <[email protected]> wrote in message
news:[email protected]...
>
> "daveornee" <[email protected]> wrote in message
> news:[email protected]...
> >
> > Is all the factory machining gone?
>
> Long gone!
>
> >Do you clean your rims and brake shoes regulary, particularly after wet rides?
>
> No. I mainly commute. In the winter, most rides are wet to some extent.
>
There's your answer. Riding in the wet/nasties means accelerated brake track wear.

You must not mtn bike too much...

Mike
 
"Matt O'Toole" <[email protected]> wrote in message
news:[email protected]...
>
> Wear indicators are nice, but you can determine wear the old fashioned
way.
> Measure your rim with a caliper, sidewall to sidewall, and compare it to
the
> spec for a new one. A little concavity is not necessarily a problem --
sidewall
> thickness is.
>

I just measured the rim width. At the outside diameter, it's 20.5mm whereas at the inside diameter
it's 19.0 mm. Harris Cyclery quote the rim width as
19.6mm.

Assuming the rims start parallel sided, this seems to suggest that the rims are worn down by 0.3mm
per side at the inside diameter and flared out at the outside diameter. Unfortunately, this still
doesn't allow me to determine the minimum thickness of the sidewalls.

Phileas
 
On Sun, 15 Feb 2004 09:55:39 -0800, "Mike S." <mikeshaw2@coxDOTnet>
may have said:

>
>"jim beam" <[email protected]> wrote in message news:[email protected]...
>> try ceramics. they're designed specifically for high wear life.
>>
>
>Normally, I don't recommend ceramic rims even though I own a pair. BUT, in this instance: wet
>commuting, it makes sense.
>
>Just make sure you get some ceramic brake pads.

ITYM "pads made for use with ceramic rims".

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Yes, I have a killfile. If I don't respond to something,
it's also possible that I'm busy.
Words processed in a facility that contains nuts.
 
Mike S. wrote:

> Normally, I don't recommend ceramic rims even though I own a pair. BUT, in this instance: wet
> commuting, it makes sense.

Just curious. Why wouldn't you recommend ceramic rims? They claim is gives better braking and wear.
Or is it because only mavic ( afaik) makes them?
 
gvw wrote:

> Mike S. wrote:
>
>> Normally, I don't recommend ceramic rims even though I own a pair. BUT, in this instance: wet
>> commuting, it makes sense.
>
> Just curious. Why wouldn't you recommend ceramic rims? They claim is gives better braking and
> wear. Or is it because only mavic ( afaik) makes them?

I've seen them from Bontrager, and others too. Ceramic rims are a bad idea. First, the ceramic
coating tends to flake off. Second, they don't brake as well, wet or dry, even if special ceramic-
compatible pads are used. This is because the ceramic is an insulator, which prevents heat from
being transferred into the metal, where it is dissipated into the air. Instead, the pads just get
hotter and hotter, until they go soft or melt, causing brake fade. The pads wear quickly too.

For situations where rim wear is a problem, such as muddy mountain biking, disc brakes are a
better solution.

Matt O.
 
"Werehatrack" <[email protected]> wrote in message
news:[email protected]...
> On Sun, 15 Feb 2004 09:55:39 -0800, "Mike S." <mikeshaw2@coxDOTnet> may have said:
>
> >
> >"jim beam" <[email protected]> wrote in message news:[email protected]...
> >> try ceramics. they're designed specifically for high wear life.
> >>
> >
> >Normally, I don't recommend ceramic rims even though I own a pair. BUT,
in
> >this instance: wet commuting, it makes sense.
> >
> >Just make sure you get some ceramic brake pads.
>
> ITYM "pads made for use with ceramic rims".
>

Yup. Pads made out of ceramic wouldn't work so well... Can you imagine the wear? Ugh!

Mike

-
> My email address is antispammed; pull WEEDS if replying via e-mail. Yes, I have a killfile. If I
> don't respond to something, it's also possible that I'm busy. Words processed in a facility that
> contains nuts.
 
Mike S. wrote:

> "Werehatrack" <[email protected]> wrote in message
>
>> ITYM "pads made for use with ceramic rims".
>
> Yup. Pads made out of ceramic wouldn't work so well... Can you imagine the wear? Ugh!

Okay, stop it, you guys. You're giving me the nails-on-chalkboard shivers.

--
Benjamin Lewis

A small, but vocal, contingent even argues that tin is superior, but they are held by most to be the
lunatic fringe of Foil Deflector Beanie science.
 
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